fall2015physicscover new outln.pdf 1 11/4/15 3:07 pm · 2020-01-01 · of prokaryotes – bacteria...

C

M

Y

CM

MY

CY

CMY

K

Fall2015PhysicsCover_NEW_OUTLN.pdf 1 11/4/15 3:07 PM

DEAR ALUMNI, PARENTS, COLLEAGUES, AND FRIENDS,

Greetings from Berkeley!2015-2016 is shaping up to be an incredible year for Berkeley Physics. This issue of Physics at Berkeley profiles groundbreaking research our faculty is conducting in the areas of biophysics and quantum materials, remembers the

lives of esteemed colleagues Eugene Commins and Charles Townes, and summarizes the past year in the department, with faculty, staff, students, and alumni.

As I begin my third year, I am still proud and humbled to be Chair of this remarkable department. Berkeley Physics grows stronger each year – whether through expanding the frontiers of fundamental physics research, educating the next generation of scientific and educational leaders, or continuing to produce an impact on the community commensurate with the distinguished history and tradition of this great department. There are good reasons why Berkeley Physics is #1 - again!

In August, the 2015 Academic Ranking of World Universities identified Berkeley Physics as the top physics department worldwide for the second year in a row. This ranking reflects the combined research accomplishments of our students, faculty, and alumni as well as the unmatched support and loyalty of our friends and staff. I am thrilled to see that Berkeley continues to demonstrate to the world the critical role that public research universities play in advancing research, education, and service. I am grateful every day to be part of such a distinguished institution.

UNDERGRADUATE DIGSAs I write, construction is proceeding on the new Reading Room and Collaboration Center on first floor of LeConte Hall, set to open in early 2016. This newly designed space, accessible from the main entryway of our building, will welcome all Cal students to Berkeley Physics and provide a central home for our majors. The center provides space for quiet study and collaboration, social interaction, and tutoring. It’s designed to enhance the undergraduate experience by supporting study, active learning, mentoring, advising, diversity, and community. Your continued support is appreciated in making this center a completed reality for our students. I hope to see many of you at the opening in 2016!

PHYSICS MAJOR CURRICULUMBerkeley Physics is proud to graduate more physics majors than any other research university in the country – a statistic verified by the American Physical Society. We are even prouder of the students themselves, who eagerly embrace their opportunities here at Cal. We have 350 majors, and graduate roughly 120 physics undergraduate majors each year. Faculty

and staff are dedicated to maintaining the best education and career opportunities for these students. Toward this goal, we have been actively planning several major revisions to our undergraduate curriculum, which we will roll out in stages over the coming years.

Starting with the freshman curriculum, these revisions will better prepare students to take advantage of research opportunities, maximizing their participation as undergradu-ates in cutting-edge research at Berkeley. The revisions will also create more flexibility in the curriculum during junior and senior years, allowing students to better specialize for careers in industry, teaching, or academic research.

The first of the curriculum changes began this year, with the introduction of two new courses. This Fall, we are offering “Introduction to Mathematical Physics,” a course designed to launch majors into their sophomore year with all the math tools they need to master higher-level physics subjects. In the Spring, we are offering “Introduction to Computational Techniques in Physics,” a freshman course designed to introduce students to basic concepts for solving physics problems numerically, a powerful tool for succeeding in class and preparing for research.

Next year, we hope to introduce two new laboratory courses, “Introduction to Experimental Physics I & II,” designed specifically for freshman physics majors. More challenging and quantitative than our current undergraduate laboratory classes, which are targeted to the broader Cal undergraduate population, the new classes will enable freshman physics majors to begin exploring hands-on physics from the very start of their Cal adventure. These two lab courses will also better prepare students for upper-division work in the Donald A. Glaser Advanced Lab. Making these new lab courses a reality will require support from our Berkeley Physics friends and family. Stay tuned for more details!

ENSURING A SAFE, NURTURING CAMPUS ENVIRONMENTYou might have read about recent events involving sexual harassment on the Berkeley campus. This kind of behavior simply cannot be tolerated, and the Berkeley Physics faculty and staff have made it a top priority to create a respectful and welcoming atmosphere, starting from within our own department.

As a first step, our faculty released a statement that reads, in part, “As faculty members in the UC Berkeley Physics Department, we stress our own commitment to developing and maintaining a supportive and open environment, free of sexual harassment and fear of retribution.” We are now developing department programs to ensure we have the type of community that complements our world-renowned research, faculty, and students. We are committed to this process and I look forward to updating you on our progress.

Thank you again for your support. Fiat lux!- Steve Boggs

LETTER FROM THE CHAIR

17Invited Lectures

18Remembering Eugene Commins

20Remembering Charles Townes

22Faculty Q&A Barbara Jacak, Nuclear Physicist

23Alumna Profile

Lorraine Sadler uses physics to help protect the nation

24Department News

30Faculty News

34Physics in the Media

Excerpts from print, online, and broadcast media coverage of Berkeley physics research

40Student Affairs

44Commencement 2015

46Class Notes

48Historical Moment

2Biophysics at Berkeley

4Protein Motors and Telomere End Caps

Tracking cargo transport along cellular highways and learning how telomeres protect chromosomes

10Evolutionary Biophysics

Combining physics theory with experimental biology to study population-scale biological phenomena

14Quantum Materials Finding new physics by creating new materials

Using physics to understand the complexities of living matter

Biophysicsat Berkeley

BIOPHYSICS seeks to uncover

fundamental rules behind the emergence

of structure and function in living

matter – to reveal how physical laws

govern biological processes, and how

the modeling of biological processes can

shed light on the nature of physical laws.

Biophysics is broadly interdisciplinary,

populated with experts from the fields of

physics, biology, chemistry, biochemistry,

engineering, medicine, epidemiology,

mathematics, and computer science.

This combination of disciplines has

led to groundbreaking advances in the

understanding of a variety of living

systems, from deciphering the structure

and function of proteins and the DNA

double helix, to the sequencing of

genomes, to the direct imaging and

manipulation of individual biological

molecules within living organisms.

Carlos Bustamante, Berkeley Physics

Professor and world-renowned biophysics

pioneer, puts it this way: “I believe a

great deal of the excitement in biological

research is taking place at the interface

between biology and these other

disciplines, and that significant increase in

our understanding of biological processes

is resulting from development of novel

methodologies arising from this interface.”

Several members of the Berkeley physics

faculty are deeply immersed in biophysics

research. This issue of Physics at Berkeley

spotlights their work, with special focus

on discoveries recently achieved by

Professors Ahmet Yildiz and Oskar

Hallatschek.

Fall 2015 | Physics at Berkeley 3

4 Physics at Berkeley | Fall 2015

he cytoplasm of a eukaryotic cell teems with molecules and organelles travelling from sites where they are manufactured to where they are needed. Waste materials are col-lected and disposed of. How are these activities organized? How are materials transported? These are

some of the questions Assistant Professor Ahmet Yildiz is helping to answer. He is an experimental biophysicist who uses highly precise single-molecule imaging and manipulation methods to study fundamental biological processes that take place inside the cell.

PROTEINS THAT WALKA primary research focus of Yildiz and his colleagues is the structure and function of motor proteins involved in intra-cellular transport. The relatively small, non-nucleated cells of prokaryotes – bacteria and other single-celled organisms–rely on simple diffusion to distribute materials throughout the cell. But for the large, complex cells of eukaryotes – multicellular organisms whose cells contain nuclei – more rapid transport mechanisms are needed.

“Eukaryotic cells are like metropolitan cities,” Yildiz points out. “They require the transport of a variety of materials to many destinations. For example, a nerve cell might be a meter long and only a few microns in diameter.

Materials prepared at one end, in the cell body, have to be transported to synapses at the opposite end. Diffusion along the length of this cell could take years.”

Eukaryotic cells have a way around this limitation. Intracellular transport is accomplished by complex protein motors that carry cargo as they “walk” along tracks formed by the microtubules and actin filaments of the cytoskeleton.

Yildiz compares the structure of these proteins to the bipedal structure of the human body. “We can use that analogy to name the different domains of these proteins,” he says. “We can say they have two feet, two legs, a body, and two arms. With their arms they hold the cargo. With their feet they walk along actin or microtubules. By consuming ATP energy, they take tiny little steps, on the order of nanometers (nm), along the track.”

“There are many kinds of motors with a wide variety of biological functions,” he continues. “What we try to understand is the machinery of these motor proteins, how they convert the energy of ATP hydrolysis into force and unidirectional motion.”

KINESIN AND DYNEINIn the initial years of his research, Yildiz deciphered the walking behavior of a protein motor called myosin, which travels along actin filaments. The conventional myosin motor is involved in muscle contraction, but other members of the myosin family are involved in other functions, including

Protein Motors and Telomere End CapsTracking cargo transport along cellular highways and learning how telomeres protect chromosomes


cargo transport. During his postdoctoral work, Yildiz shifted focus to two other classes of protein motors, kinesin and dynein, which travel in opposite directions along microtubules.

Microtubules are polar fibers that not only serve as transport routes within the cell, but also help define the cell’s shape. The minus end of a microtubule originates at an organelle called the centrosome, usually located near the center of the cell. The plus end of a microtubule is located near the cell’s periphery. Kinesin moves toward the plus end of a microtubule, dynein toward the minus end.

“Kinesin is probably nature’s smallest bipedal walker,” Yildiz says. “It takes steps only 8nm long, about 50-100 steps a second, as it transports large organelles.”

The mechanics of kinesin and myosin are similar: both protein motors follow a stepping model that is highly coordinated. “These motors place one ‘foot’ in front of the other.” Yildiz adds. “Their two feet function together as a single cyclic machine, very much like human walking.”

Dynein, on the other hand, is a larger molecule with a more complex pattern of motion. Dynein can take sideways and backward steps as it travels along the microtubule, enabling it to move around obstacles. “This ability may be important for the regulation of its motility inside cells, since we know that microtubules are densely covered with roadblocks,” Yildiz notes. “Kinesin, which cannot take a sideways step, stalls and sometimes even falls off when it encounters an obstacle.”

Dynein transports cargo from the center of the cell toward the periphery. It also positions organelles at proper locations in the cell by anchoring them to microtubules. And it helps form the cell’s shape by pulling and stretching microtubule filaments.

“Dynein is basically two individual machines that are elastically coupled.” Yildiz explains. His research has clarified the mechanics of dynein motion – how the two machines move relative to each other – as well as answering questions about how the motor extracts energy from ATP and what drives the polarity of its motion.

Ahmet Yildiz (front) is an experimental biophysicist who uses highly precise single-molecule imaging and manipulation methods to study fundamental biological processes that take place inside the cell. He is shown here with graduate students Alex Chien (left) and Luke Ferro.


TINY STEPS, TINY FORCES“We cannot directly see these motors in a microscope, because they’re too small,” Yildiz notes. “But we can label their feet with a fluorescent probe, a dye molecule that emits light at a specific wavelength.” He uses biochemical methods to tag the feet of a motor protein with different colored fluorescent probes, a bit like putting a different colored light on each shoe of a person walking in the dark. Light emitted by the probe enables him to track the relative motion of the feet in real time.

“We can look at the position of a single dye molecule with nanometer precision,” he explains. “This capability allows us to track the tiny steps the motor takes as it moves.”

Yildiz first developed this high-precision fluorescent imaging technology early in his career, while working on

CARLOS BUSTAMANTE – SINGLE-MOLECULE MANIPULATION

What are the mechanical forces that maintain the structure of DNA, RNA, and proteins? How do molecular motors convert chemical energy into mechanical work?

Professor Carlos Bustamante, a member of the Berkeley faculty since 1998, is a Howard Hughes Medical Investigator. His pioneering work in biophysics includes being the first scientist to develop techniques for mechanically manipulating, observing, and measuring single biological molecules in real time. His laboratory continues to develop novel methods of manipulation, using magnetic traps, laser-based optical tweezers, atomic force microscopy, and fluorescence microscopy.

The overall objective of Bustamante’s research is to elucidate the molecular mechanisms underlying the cellular machinery involved in DNA replication, DNA transcription, and RNA translation. Past achievements include the first high-precision measurements of mechanical properties of DNA, tracking single ribosomes as they translate RNA codons into amino acids (the initial step in manufacturing a protein), characterizing the mechanism of ring-ATPases (motors involved in many cell functions, including protein unfolding), and discovering new details about how the enzyme RNA polymerase transcribes DNA in eukaryotic cells.

Today, the Bustamante group continues to explore the structure and function of DNA-protein interactions and their effect on gene expression. Recent experiments on the mechanical properties of protein folding show, for the first time, how the ribosome controls the folding process and the speed and efficiency of protein synthesis. Research also continues on the dynamics of molecular motors that bind DNA, including motors involved in the packaging of viral DNA.

Ahmet Yildiz came to Berkeley in 2008, after a postdoctoral stint at University of California San Francisco. His many honors include a Presidential Early Career Award, an NSF Career Award, and an Alfred P. Sloan Fellowship.

Kinesin and dynein are molecular motors that utilize the energy of ATP hydrolysis to walk along microtubule filaments inside cells. These motors carry organelles, vesicles, and protein particles as a cargo. Kinesin walks along a unipolar array of microtubule toward the plus ends, whereas dynein walks towards the minus-end.


myosin. At that time, previous versions of the technology had reached a tracking ability with 10-20 nm precision, a value considered to be the practical limit for single molecule fluorescent imaging. The high-precision improvement was a groundbreaking achievement that has led to numerous awards for Yildiz and has been enthusiastically adopted by biophysics laboratories worldwide.

EXPERIMENTS INSIDE LIVE CELLSOnce Yildiz and his research team understand the mechanics of a protein motor, they can begin applying their experimental protocols to living cells. “We carry out experiments inside the living cell by labeling either the cargo or the motor with fluorescent tags,” he says. “We want to explain the dynamics of the whole transport process, how cells control where cargo is delivered, how motors dissociate from cargo, and how the direction of travel changes when reassembled cargoes are carried back by the oppositely polarized motor.”

The living systems Yildiz has chosen for this aspect of his work are organelles called cilia – cell protrusions involved in sensing environmental cues and moving fluids across cell surfaces. Cilia make good subjects because they are isolated from the rest of the cytoplasm, contain relatively few compo-nents, and are rich in microtubules of known polarity.

“In the cilia,” Yildiz explains, “all of the microtubules are oriented in the same direction. They have the same polarity, and they are rigid. All kinesins go the same direction, and all dyneins come back in the opposite direction. This is not a luxury you have inside the cytoplasm, where the micro-tubule polarities are mixed and highly dynamic. A complex problem is reduced to one dimension.”

“You have the cell body site, like train station A, and the tip of the cilia, which is station B,” he continues. “Cargos shuttle back and forth between these two stations. If we can understand what’s going on in those two turnaround zones, we may solve the whole transport phenomenon.”

TELOMERES AND SHELTERINOther questions Yildiz and his colleagues are addressing involve telomeres – specific DNA sequences located at the ends of linear chromosomes. Among the important functions of telomeres is the protection of chromosomes during repli-cation: every time a chromosome is copied, it gets slightly truncated at each end due to inherent limitations of the DNA synthesis machinery. By padding the ends of their chromo-somes with telomeric sequences, cells gain the ability to divide many times before the truncations start cutting into useful genetic information.

Telomeres also ensure that the natural end of a chromo-some is not mistaken for broken DNA that needs repair.” Our DNA gets broken all the time,” Yildiz explains, “from oxidation, exposure to UV light, and metabolic activities.” A wide variety of enzymes chemically recognize DNA breaks and repair them. “If the natural end of a chromosome is not protected, it can be inappropriately repaired,” he points out. “In humans, telomeric DNA recruits a specific six-protein complex called shelterin, which shields telomeres from DNA repair enzymes.” Shelterin also regulates the activity of telomerase, an enzyme that adds length to telomeres.

In reproductive cells and stem cells, telomere length is maintained because telomerase is active. In somatic cells – that is, most body cells – telomerase expression is shut down. As a result, telomeres get slightly shorter each time the cell divides. At a certain point, telomeres become so short that the cell stops dividing, a condition referred to as senescence.

“Telomerase can potentially be used for anti-aging therapy. However, it is still under debate whether telomerase-based telomere elongation is the ‘Fountain of Youth’ that countless people, from Gilgamesh to Ponce de Leon, were seeking.”

–AHMET YILDIZ

(Top) Chlamydomonas is a green algae that glides on solid surfaces by adhering both of its cilia. In order to elongate and maintain cilia, proteins need to be transported back and forth between cell body and ciliary tip by kinesin and dynein motors. (Bottom) Yildiz and his group color-code individual cargoes to reveal their velocity and directionality.


“Somatic cells age because the mechanisms that keep telomeres long are turned off,” says Yildiz. “Telomeres serve as a biological clock that determines the lifespan of cells. Telomerase can potentially be used for anti-aging therapy. However, it is still under debate whether telomerase-based telomere elongation is the ‘Fountain of Youth’ that countless people, from Gilgamesh to Ponce de Leon, were seeking.”

“Telomeres are also one of the cell’s most powerful anti-tumor mechanisms,” he adds. Tumor cells are essentially immortal – they continue dividing indefinitely. Even if a somatic cell has the potential to become malignant, the loss of telomere length eventually stops it from dividing, because telomerase is inactive in those cells.

Reactivation of telomerase expression through specific mutations in the genome – allowing cell division to continue unabated – is the hallmark of most human cancers. Telomerase inhibition can be a powerful approach to stopping cancer proliferation, and drugs that inhibit telomerase are in clinical trial. Chemotherapy drugs currently in use target the micro-tubule network and the cell division machinery in all cells. Drugs targeting telomerase are not expected to affect non-cancerous somatic cells.

RECONSTITUTING TELOMERES ON A MICROSCOPE SLIDEYildiz and members of his research group recently succeeded in purifying the shelterin protein complex, for use in studying the dynamics of its interactions with DNA, telomerase, and other proteins. “Our job,” he says, “is to gain molecular insight by doing single molecule experiments in purified complexes outside of the cell.”

“We assemble the purified shelterin complex on the telo-meric DNA,” he explains, “to see how it interacts with DNA repair enzymes and with telomerase. We aim to find out how shelterin antagonizes DNA repair enzymes while allowing access of telomerase to the telomere terminus.”

“Once we purify a system,” he adds, “we can manipulate it to see which parts of the protein are essential for important functions. We want to get deeper mechanistic insight about the biological function.”

SINGLE-MOLECULE FRET AND OPTICAL TRAPPINGA major challenge in light microscopy is the need to go beyond the diffraction limit of optical microscopy, which is around 250 nm. Individual proteins have a size scale of just a few nm. “Also,” Yildiz points out, “the cell is incredibly crowded. The optical tools we develop allow us to monitor individual protein complexes in the midst of all these highly crowded proteins.”

To meet this challenge, he has continued to build upon high-precision fluorescence imaging techniques. One of the methods his group uses is single-molecule FRET (Fluorescence Resonance Energy Transfer). They’ve designed a model telomere that is tagged with two fluorescent dyes. When proteins bind to the model telomere, distance between the two dyes changes due to the remodeling of DNA. “We

Optical pathway of the dual-beam optical trapping microscope used in the Yildiz Lab.

(Left) Fluorescence image of human chromosomes stained with blue dye. These cells are arrested during the phase of cell division in which condensed duplicated chromosomes are still linked together. Telomeres, stained with a green dye, are located at the ends of chromosomes. (Right) Yildiz has shown that telomeres are uniquely organized into tight chromatin structures by the shelterin protein complex. Telomeric chromatin regulates the protection and elongation of the chromosome ends.


measure energy transfer between the two fluorescent dye molecules,” Yildiz explains. “Based upon the energy transfer efficiency, we can determine which proteins bind to the DNA, and how they compete against each other.”

“We do this without seeing the proteins at all,” he continues. “We can tell whether it’s shelterin, telomerase, or a DNA repair protein that is binding to the DNA, and learn about the dynamic interactions between them.”

The group also uses optical trapping to observe how telomerase adds DNA to telomeres. “The trap consists of two focused laser beams, each holding a microscopic bead. One bead is attached to a DNA strand, and the other to telomerase. When telomerase binds to the DNA, it completes a physical tether between the two beads. Recent developments in optical trapping by Berkeley biophysicist Carlos Bustamante and others in the field enable measurement of angstrom-scale steps at 100 Hz time resolution, at room temperature, in water,” Yildiz reports. “This amazing technical ability allows us to make real-time observation of the synthesis of new tracts by a single enzyme.”

ADVANCING THE FIELDMaking precision measurements like these means putting together a research team with capabilities in physics, chemistry, and biology. The Yildiz Lab includes students and postdocs from each of these areas. “We want a good mixture of expertise, so biology and physics can merge properly,” he says.

The highly advanced methods and models he and his team have developed can be applied to many biological systems, not just those currently under study. His goals include understanding and perhaps even emulating machinery found in living cells. “We would like to find complex systems in nature that our theories can apply to,” he says. “Once we understand how a system works, we can manipulate it. Eventually, our understanding might allow us to engineer new protein machines and control their activity to perform specific functions inside cells.” n

“Making precision measurements like these means putting together a research team with capabilities in physics, chemistry, and biology... We want a good mixture of expertise, so biology and physics can merge properly.”

—AHMET YILDIZ

NAOMI GINSBERG – NANOSCALE IMAGING OF BIOLOGICAL DYNAMICS

What biomolecular organization promotes energy transfer in photosynthesis?

Professor Naomi Ginsberg joined the Physics Department in 2011, bringing with her an extensive background in chemistry, physics, and engineering. She develops novel, high-resolution imaging methods for exploring the physics and chemistry of molecular phenomena, including solar energy conversion in

plant photosynthesis and in photovoltaic materials.

Currently, Ginsberg’s research team is developing cathodoluminescence-activated microscopy – a combination of electron and optical microscopy that improves upon existing techniques for observing complex molecular interactions at the nanoscale. This new technique is used to image soft materials, including photosynthetic membranes, at electron beam resolution and without any electron beam-induced damage.

The group also develops ultrafast, super-resolution, and cathodoluminescence microscopy techniques to measure nanoscale homogeneities in the optoelectronic properties of organic electronic films. The goal is to reveal microscopic mechanisms that limit the macroscopic transport and power conversion efficiencies of transistors or photovoltaic devices, as a first step in finding ways to overcome those limitations.


ow do genetic mutations and adaptations disperse through a population? What factors influence the spread of disease epidemics? How do environmental conditions affect the growth and behavior of microbial colonies? How fast is evolution?

These are among the questions Professor Oskar Hallatschek is helping to answer. He uses quantitative and statistical methods from theoretical physics,

along with laboratory studies in experimental biology, to investigate evolution, population genetics, and population-scale biophysics in microbial communities.

Biophysics is well established in the regimes of molecular or cell biology, but Hallatschek is excited about larger scales of organization. “I’m interested in studying phenomena that emerge at the level of populations,” he says. “Evolution is one of those phenomena. We are trying to see if we can use quantitative theories to predict outcomes of evolution.”

LOCATION, LOCATION, LOCATIONEvolution proceeds from genetic mutations that influence an organism’s fitness for survival and reproduction. Hallatschek has made important discoveries about how strongly the spatial arrangement of individual organisms in a population influences the spread of mutations.

In research published in 2007, he and colleagues conducted laboratory experiments on two experimental strains of bacteria that grow at the same rate. The experiments demonstrated that bacteria cells closest to the outer edge of a population multiply more quickly than those in the interior. As a result, even though a 50:50 blend of the two experimental strains was thoroughly mixed at the outset, they separated from each other as their populations grew.

A colony of the bacterium E. coligrown from mixtures of differently labeled strains exhibit a clear segregation pattern, due to enhanced number fluctuations (“genetic drift”) at the growing front. [from PNAS 104/50, 2007.]

Evolutionary BiophysicsCombining PHYSICS THEORY with EXPERIMENTAL BIOLOGY to study population-scale biological phenomena

“I’m interested in studying phenomena that emerge at the level of populations. Evolution is one of those phenomena. We are trying to see if we can use quantitative theories to predict outcomes of evolution.”

—OSKAR HALLATSCHEK

Oskar Hallatschek joined the Berkeley physics faculty in 2013. From 2009 to 2014, he was head of the Biological Physics and Evolutionary Dynamics program at Max Planck Institute in Germany. In 2014 he was selected as a Simons Investigator in Mathematical Modeling of Living Systems. (Sarah Wittmer)


These experimental results not only illustrated a way in which random effects – in this case, the chance arrangement of cells in a growth medium – influence growth patterns. They also provided the first direct evidence that spatial arrange-ment strongly affects the spread of mutations through a population: bene-ficial mutations in cells located at the forefront of growth in a microbial col-ony are more likely to spread than equally beneficial mutations in cells located farther from the growing edge.

“In the case of an expanding colony, it’s all about location,” Hallatschek reported in Quanta magazine in 2013. “Even if you are a highly fit mutant, you have to be at this frontier to really thrive.”

BIOFILMS AND ANTIBIOTIC RESISTANCEA primary characteristic of many species of bacteria and fungi is their habit of forming biofilms – dense, sticky com-munities of cells that adhere to each other and to surfaces so thoroughly that they are very difficult to break apart or dislodge. Biofilms are ubiqui-tous in nature and industry. Examples range from dental plaque and human disease pathogens to colonies that contaminate hospital equipment or clog industrial pipes.

Hallatschek’s research team has demonstrated how the spatial arrange-ment of cells in biofilms influences evolutionary phenomena, including development of antibiotic resistance among disease-causing microbes.

“Antibiotic resistance is a serious health problem,” he asserts. “Bacteria typically develop resistance to a new antibiotic on a time scale of about three years from the time the antibiotic is introduced. We can ask: What controls this time scale? Can we predict this quantitatively and measure it in the lab?”

Hallatschek’s work with biofilms has already pinpointed at least one way in which previous theoretical assumptions limited the ability to accurately model the evolution of antibiotic resistance.

“Let’s say you have a well-mixed popu-lation of bacteria in a beaker of liquid,” he explains, “and you mix the liquid so that all cells interact with each other. You can do such an experiment in the lab, with well-shaken environments. Then you add a high dose of antibiotics, presumably lethal. The cells don’t have any time to evolve, because all of them are immediately seeing a lethal dose.”

Survival of the bacterial population then depends on drug-resistance muta-tions that happen to exist prior to the drug treatment. In well-mixed popula-tions, the pattern of such pre-existing mutations was characterized by physi-cists Max Delbrück and Salvador Luria in a seminal combination of experiment and theoretical analysis published in 1943. These results are used frequently to predict how bacteria respond to drug treatment.

However, Hallatschek’s laboratory has now measured patterns of pre-existing mutations in biofilms and discovered that they are inconsistent with the Luria-Delbrück results. To resolve this discrepancy, Hallatschek’s laboratory develops models that take into account the spatial arrangement of microbes that form biofilms. These models reproduce the patterns seen in the experiments, and show that pre-existing mutations are like a frozen record of the spatial growth process of the biofilm.

Pre-existing drug-resistance mutations in a microbial colony. a) Simulation of resistance mutations (red) appearing during growth of a colony. Two types of clones are visible: Sectors, which successfully surf at the growing edge of the colony, and bubbles, which are trapped in the bulk of the colony by the wild-type population. b) Live colonies grown from single cells of a yeast strain mutating from one fluorescent state (RFP - dark green) to another (GFP - bright green) also show bubbles and sectors.

HERNAN GARCIA – PHYSICAL BIOLOGY OF LIVING EMBRYOS

How does a single cell develop into a multicellular organism?

Hernan Garcia joined the Berkeley physics faculty earlier this year. His research focuses on understanding how a single cell develops into an organism composed of billions of cells of many types, such as those found in muscle, liver, and the brain.

Cells adopt these different fates by making decisions about which genes to express and, more importantly, when, where, and how to express them. These decisions are dictated by the code written in each organism’s DNA. Garcia is working to uncover the rules behind cellular decision-making during development. His objective is to predict and manipulate developmental programs by looking at the DNA sequence.

Garcia and his research team combine physics, synthetic biology, and new technologies to query and control developmental decisions in real time at the single-cell level in the fruit fly embryo, a classic model for embryonic development. Garcia is co-author of the book Physical Biology of the Cell, together with Rob Phillips, Julie Theriot, and Jane Kondev. The text is used in the Physics Department’s “Principles of Molecular Biophysics” course.


In ongoing theoretical work, he and his colleagues are exploring how the gradient of antibiotic concentration allows cells to gradually adapt, with some cells in the population eventually gaining the ability to survive even at the exposed edge of the biofilm. “It’s almost a breeding process,” he reports. “The presence of this spatial structure can offer a huge advantage for devel-oping antibiotic resistance.”

MODELING EPIDEMICSThe approaches Hallatschek has devel-oped for modeling the dispersal of mutations is similar to the approach he is using to model the dispersal of disease pathogens in a population. In 2014, his laboratory created a model capable of quantifying how fast a disease can spread, particularly when diseased individuals make long-distance jumps across territory.

Air travel, for example, is a mech-anism for long-range jumps of patho-gens carried by humans. “That can lead to very rapid spread of diseases like influenza,” Hallatschek says. “Until our work, it was not understood what to expect when including long-range dispersal in even the simplest epidemi-ological models.”

Epidemiologists routinely run computer simulations to model the spread of a disease epidemic. Because epidemics can spread so quickly, simu-lations are often used to reconstruct dispersal patterns after the fact, to get a better picture of what happened. Prior to this latest contribution from Hallatschek’s lab, it wasn’t clear which features of an epidemic were important to a simulation’s accuracy.

“You want to simplify, to remove features that are irrelevant to the broad behavior of the process you’re study-ing,” Hallatschek explains. “It’s clear that jump distribution is important, but certain types of chance effects had been neglected before we developed our work.” His new model takes into consideration the randomness associated with long-range jumps in distribution,

and thus gives much more accurate results compared to previous attempts.

“The ideal model is as simple as possible yet as complex as necessary, and I think we have provided that,” he adds. “It will have to be adapted for particular diseases – influenza, ebola, others – but the basic core will remain.” Hallatschek is collaborating with Berlin epidemiologist Dirk Brockmann of the Robert Koch Institute in Germany to fine-tune the model.

GENOME SEQUENCINGIn recent years, researchers have begun to incorporate genome sequencing data into efforts to quantify both disease epidemiology and evolutionary phenom-ena. “As a virus is spreading in space,” Hallatschek points out, “it’s also mutating, evolving very rapidly. Even more rapidly than bacteria developing antibiotic resistance.”

Most mutations are neutral, which means they don’t affect fitness. “That makes them useful as markers,” Hallatschek says, “like a tracer for the spread of the pathogen.” Spatially laying out the pattern of tracer mutations can be helpful when reconstructing the history of an epidemic.

However, genome sequencing produces enormous amounts of data that require careful filtering and analysis to extract useful information. “Genome data is very, very noisy,” Hallatschek emphasizes. “The need on the theoret-ical front is to make sense of all the data, and that’s where statistical physics comes in. Most approaches to extract-ing signal from this noisy data invoke complex black-box algorithms that are often applied out of context. Our

MICHAEL DEWEESE – NEURAL MECHANISMS OF SELECTIVE AUDITORY PROCESSING

How do we focus attention on important sounds in a noisy environment?

Michael DeWeese joined the Berkeley physics faculty in 2007, following six years of postdoctoral research at Cold Spring Harbor Laboratory in NY. His laboratory focuses on neural mechanisms involved in selective auditory attention – the ability to attend to desired sounds while ignoring others. His goal is to understand how auditory attention is controlled by the brain.

Isolating a single signal from a noisy background poses a challenge for even the fastest computers. Solving this computational problem could offer insight into the workings of the conscious mind, lead to designs for machines that can intelligently process real-world data, and make inroads toward cures for diseases characterized by the inability to focus, including autism and attention deficit disorders.

DeWeese and his research team combine recent advances in experimental neuroscience and animal behavior studies with computational modeling. They are developing a rodent model of selective auditory attention that can be explored using electro-physiological, optical, and molecular techniques originally developed for cellular-level investigations.

“The ideal model is as simple as possible yet as complex as necessary, and I think we have provided that.”

—OSKAR HALLATSCHEK


approach is to come up with minimal methods to learn about evolutionary history based on genome sequencing data.”

Hallatschek’s investigations of the demographics of evolution are not just theoretical. He and his lab associates are also employing experimental meth-ods. By observing the growth of a microbial colony in a Petri dish, they can document a known demographic history for that population. “Then we scrape off the colony,” Hallatschek says, “and send it for sequencing. And we see if we can use the sequencing data to reconstruct this known demo-graphic history.”

BIOMECHANICS OF BIOFILMSHallatschek and his students are also devising novel experiments and devel-oping models to explore how biome-chanical forces influence biofilms. “If a cell in a very dense population wants to grow, it needs to push apart its neighbors to make a place for itself,” Hallatschek explains. “We want to know how large these forces can become, how

they feed back on the behavior of the cells, and how important they are for evolution.”

With postdoc Morgan Delarue, he is conducting experiments in which yeast cells are given unlimited resources but limited space. Microfluidics are being used to create growth chambers with a fixed volume. “These are micrometer-scale chips that allow you to mold chambers that are permeable to nutrients but not yeast cells,” Hallatschek says. Cells cannot grow beyond the walls of the chamber. Conditions like this exist in a variety of situations in nature and industry, such as in pores between soil particles and inside pipes and tubes.

The experiments have revealed that as the cells proliferate and space becomes increasingly constrained, very large forces are generated. (Large enough, in fact, to break through the chamber walls in the earliest versions

of the experiment – an event that sparked an innovative redesign.) When the pressure becomes high enough, the cells lose their spherical shape. Their reproductive cycle also slows.

“There are many questions involved here,” Hallatschek remarks. “Do these forces modify microenvi-ronments, maybe even destroy them? What’s the implication for the invasion of pathogens? How do these forces regulate cell behavior?”

BACK TO THE FUTUREThere are no easy answers to the questions Hallatschek and his lab associates are exploring. “Evolution is a complex system,” he says. “It’s a lot like predicting the weather. We know the fundamental hydrodynamic equa-tions that control atmospheric air flow and so on, and still we cannot predict the weather longer than two weeks. Our first goal is to find the correct equations – like the equivalent of Newton’s equations or the Navier-Stokes equations – that will enable us to predict how evolution works over short time periods.” n

Self-driven jamming of budding yeast cells induces confinement. Microbes are grown in a growth chamber threaded by narrow nutrient channels. Jamming in the outlet leads to a partial confinement of the population and a build-up of contact pressure (top, left vs. right). As the jamming-induced pressure builds up, cells are deformed into polygonal shapes (middle), and the contact area between cells and microscope coverslip increases (bottom).

In another ambitious project, one of Hallatschek’s postdocs, Daniel Weissman, is using publicly avail-able genome sequencing data to reconstruct the demographics of human evolution. In ongoing research, Hallatschek and Weissman describe a new, innova-tive approach for tracing base pairs in the genomes of individualsto identify a common ancestor as far back as hundreds of thousands or even millions of years in human his-tory. “We call it MAGIC,” Hallatschek reports, “Minimal Assumption Genome Inference of Coalescence.” Weissman came to Berkeley in 2014 as a Simons Research Fellow, and departed in August to join Emory University as Assistant Professor of Physics.


Honeycomb Lattices and Frustrated Quantum Magnets

FINDING NEW PHYSICS BY CREATING NEW MATERIALS

Quantum Materials

WHEN HE JOINED the

Berkeley physics faculty in

2013, James Analytis already

had an outstanding reputation

as an explorer in the exotic

world of quantum phenomena

in condensed matter systems.

He creates so-called quantum

materials – novel configurations

of atoms that exhibit intriguing

technological possibilities and

offer new ways to investigate

quantum physics.

“The phrase ‘quantum

materials’ refers to macroscopic

phenomena that can’t be explained using classical analogies,” Analytis

says. “With electric current, for example, we have the classical analogy of

charged electrons moving through a metal, much like water under pressure

flows through a tube. Quantum materials, such as superconductors,

topological insulators, and quantum magnets, don’t have a classical analogy.

There’s no way to understand them unless you appeal to quantum

mechanical processes.”

“The field of quantum materials includes a lot of really interesting topics

and phenomena,” he explains, “but it’s important to remember that all

materials are actually quantum materials. Atoms bond together because of

quantum processes. Without those processes, we wouldn’t have solids,

liquids – all the everyday phenomena we’re familiar with.”

James Analytis,

Berkeley’s Charles Kittel

Chair in condensed

matter physics, came

to Berkeley after three

years as staff scientist

at the Stanford Institute

for Materials and Energy

Science. This year he

received a coveted

Department of Energy

Early Career Award

to fund his work with

quantum magnetism.


HONEYCOMB LATTICESIn research published last year, Analytis and his collaborators reported fabricating a new quantum material with properties so unique that the Department of Energy awarded Analytis a 2015 Early Career Award to support its further exploration. “We made a new material that had existed only in theory,” Analytis says, “and that no one had imagined in quite this way.”

The new material is an iridium-based oxide, or iridate, composed of lithium, iridium, and oxygen atoms. Ithas a crystal structure that Analytis describes as a honeycomb lattice – a geometric configuration reminiscent of the hexagonal structure of graphene. Graphene is a two-dimensional lattice system composed of a single layer of carbon atoms. The iridate fabricated by Analytis is a three-dimensional system composed of layers of lattices.

“Because of this material’s similar-ity to the lattice structure of graphene,” he notes, “it inherits a lot of graphene’s topological properties. But its physics is much richer.” Carbon’s atomic number is 6. Iridium is a transition metal with an atomic number of 77. “That means the iridate system has a lot more electron orbitals to play with,” Analytis says. “In many ways it combines the physics of graphene with the physics of transition metals.”

“Transition metal oxides are already known to show the highest supercon-ductivity temperatures of any com-pounds,” Analytis notes. The most famous examples are the copper oxides, which superconduct at temperatures up to 150 Kelvin (K). “The iridium oxides should inherit some of the same phys-ics,” he adds, “and possibly show a pro-pensity for high-temperature super-conductivity. We’re looking for that.” But the potential for high-temperature superconductivity is not the only intriguing property exhibited by this new iridate material. It also has exotic magnetic properties.

SPIRAL ANTIFERROMAGNETSThe magnetic properties of a material arise primarily from the spin charac-teristics of its electrons. Ferromagnetism, the strongest type of magnetism, emerges when the spins of neighboring electrons all point in the same direction. Antiferromagnetism, a weaker form of magnetism, emerges when the spins of neighboring electrons point in opposite directions.

Theorists had predicted that iridate structures would exhibit antiferro-magnetism. In reality, however, the electron spin interactions of the iridate fabricated in the Analytis Lab are more complex.

“This material exhibits a kind of magnetic order that’s never been seen before,” Analytis explains. “We found that, if you look at nearest-neighbor spins, you see that they form vortex-like objects. This is what’s called a frustrated quantum magnet – the spin doesn’t know in which direction to point, because its interactions with each of its nearest neighbors point it in different directions. The consequence is that it cannot form a ferromagnet or an antiferromagnet. It forms a spiral antiferromagnet.”

Another of the iridate’s intriguing characteristics is the ease with which its spin properties can be manipulated.

“At temperatures of around 40 K,” Analytis says, “the spins are frozen in place. Even so, you can push them around quite easily, simply by apply-ing a magnetic or electric field, or by applying pressure.”

This ease of manipulation has inspired Analytis to look for ways to incorporate metal atoms into the lattice. “I want to know what happens when you have metallic-like electrons within this spin structure,” he says. “That’s interesting because metals are actually very hard to manipulate. They conduct electricity in all directions. They’re very hard to tune in terms of switching them on or off.”

“I’m excited about learning whether you can use this complex magnetism, which can be tuned so easily, to change the direction of electric current, or to switch it on or off. And it’s not just electrons carrying charge, it’s also electrons carrying spin – it’s possible you could change the direction of spin current as well. Contrast this to a semi-conductor, which is simply on or off. A device based on these new materials could have multiple functions, all simultaneously operable. You can use these quantum properties to do some-thing useful by manipulating them externally.”

Analytis predicted a series of iridium based compounds that could be related into one family of layered compounds known as the ‘harmonic honeycomb iridates’ (Nature Communications 5, 4203 (2014)). The left shows the basic structural possibilities, with blue, red and black lines indicating iridium-iridium bonds in different crystal directions. Due to Analytis’ innovations in synthesis, the size of these materials has increased by an order of magnitude since he first grew them. The right figure shows a crystal recently grown in the Analytis lab, with the original, smaller crystal placed on top.


QUANTUM SPIN LIQUIDSThe new materials Analytis is working with might have even more intriguing features still to be discovered. These materials could shed light on the physics of spin liquids – a phase of matter known, so far, only in theory.

“In most magnetic materials,” he explains, “the electron spins will order at low temperatures, forming a ferromagnet for example. A quantum spin liquid is a mate-rial in which the electron spins cannot order, because of strong quantum fluctua-tions which arise from the Heisenberg uncertainty principle. The exciting techno-logical possibilities of these compounds is in providing a material basis for topo-logical quantum computing, by harnessing the quantum mechanical nature of the spin liquid.”

The new iridate Analytis is investigating is not a spin liquid, he says, “but it’s very close. That’s one reason why people are so excited about it. It has this weird quantum state where spin and charge are not coupled together. It’s kind of like investigating a new universe. It could offer an opportunity to explore the basic science of spin liquids. How do systems like this transport heat, carry entropy, transport spin? So many of the quantum behaviors we’ve become familiar with might not apply.”

NEW COMBINATIONSThe primary motivation in Analytis’ research is to find out if new, exotic states of matter could be created by making materials that combine the topological physics of a graphene-like honeycomb with the physics of transition metal oxides. “To mesh them into a single system,” as he describes it. But the material he has created thus far turns out to be even more interesting than theory predicted.

“What’s exciting about being an experimentalist is when you discover things theorists haven’t thought of,” he reflects.” Nature is always going to beat our imagi-nation in terms of creativity. And I like being able to make my own materials, because you’re guaranteed to get surprises.” n

TOPOLOGICAL PROPERTIES OF MATTER

In condensed matter physics, topology refers to the spatial arrangement of atoms in the interior of a solid, and how the quantum mechanical attributes of that arrangement influence electron behavior at the solid’s surface. It’s only within the past decade that scientists have become aware of topology’s important effects on the quantum properties of certain materials.

Topological insulators were the first type of topological matter to be discovered. Electrons in the interior of these solids are bound in place, as expected in an insulating material. However, the topology of the interior enables electrons on the surface to speed along with high conductivity. Berkeley physicist Joel Moore was among the first to provide a theoretical basis for this phenomenon.

Berkeley physicist James Analytis explains the concept of topology by comparing spheres and donuts. “They’re topologically different objects, he points out. “Every way of wrapping a string around a sphere is the same. But with a donut, you can go through the hole or around the edge.”

“It turns out,” he continues, “that electrons ‘know’ the topology of the system they’re in. That affects the paths they follow when they move. This extra layer of complexity results in interesting surface states arising from topological properties.” The new iridium oxide material recently fabricated in the Analytis Lab has intriguing properties that arise from its internal topology.

Analytis uses both nano-fabrication and bulk synthesis techniques to grow and manipulate materials. On the top is shown a nano-structure made using Berkeley’s Focused Ion Beam facilities. On the bottom, Analytis seals materials in quartz, a step toward their final synthesis.


The 2014 Emilio Segrè Lecture, Superconductors: Old and New, was presented by Robert Birgeneau on October 17, 2014. Birgeneau served as UC Chancellor from 2004 to 2013 and

has been a member of the Physics Department faculty since 2004. His research focuses on the fundamental physics of high-temperature superconductors and quantum magnets.

In his talk, Birgeneau reviewed progress in the field of superconductivity, beginning with its initial discovery in mercury in 1911, to the discovery of high-temperature super-conductivity in copper oxides in 1987, to recent work on iron arsenide and selenide superconductors. “Research on super-conductivity has produced theoretical insights which have implications not only for superconductivity itself,” Birgeneau said, “but for systems as varied as liquid crystal gels and the fundamental constituents of the universe.”

The 2015 Oppenheimer Lecture, Universe or Multiverse, was presented by Andrei Linde on February 23. Linde is one of the authors of the infla-tionary theory of the universe, having con-tributed elements of the inflationary scenario proposed by Alan Guth in 1981. Linde subsequently developed the theory of eternal chaotic inflation, which “suggests that our universe is one of many inflationary universes that sprout from an eternal cosmic tree.” He is presently a professor of physics at Stanford University.

In his talk, Linde described the status of inflationary theory in light of recent data from the Planck satellite. “Rather paradoxically,” he said, “this theory predicts that on a very large scale, much greater than what we can see now, the world may look totally different. Instead of being a single spherically symmetric balloon, our universe may look like a “multiverse”, a collection of many different exponentially large balloons (“universes”) with different laws of low-energy physics operating in each of them. The new cosmological paradigm, supported by developments in string theory, changes the standard views on the origin and the global structure of the universe and on our own place in the world.”

Eric Betzig, 2014 Nobel Laureate in Chemistry, presented a special public lecture, Imaging Life at High Spatiotemporal Resolution, on March 9, hosted by the Departments of Physics,

Chemistry, and Molecular and Cell Biology. Betzig is group leader at the Janelia Research Campus in Virginia. He received the Nobel Prize “for development of super-resolved fluorescence microscopy.”

In his talk, Betzig described three approaches to improving the ability to image living tissue at high resolution: super- resolution microscopy for imaging specific proteins within cells down to near-molecular resolution; plane illumination microscopy using non-diffracting beams for noninvasive imaging of three-dimensional dynamics within live cells and embryos; and adaptive optics to recover optimal images from within optically heterogeneous specimens.

The 2015 Emilio Segrè Lecture, A Random Walk in Science, was presented on October 15 by Berkeley alum and Nobel laureate Steven Chu. Chu is William R. Kenan Professor of Physics and Molecular and Cell Physiology at Stanford University. A UC Berkeley Physics alum, Chu served as 12th US Secretary of Energy, from 2009-2013, and was Director of Lawrence Berkeley National Laboratory (Berkeley Lab) from 2004-2008.

“Science does not always advance with a clear vision,” Chu said, “and scientific trajectories, unlike Newtonian mechanics, seldom follow predictable pathways. My meander-ings began at UC Berkeley with Professor Eugene Commins, followed by work at Bell Labs and Stanford.”

Chu discussed his work as Director of Berkeley Lab and as Secretary of Energy in the context of climate change and sustainable energy. He also talked about his current research efforts in biology and biomedicine.

Invited Lectures for 2014-2015Four exceptional leaders presented lectures at Berkeley Physics this past year. All can be viewed online at physics.berkeley.edu

REMEMBERING EUGENE D. COMMINSScholar, gentleman, and esteemed colleague 1932-2015

Berkeley Physics Professor Emeritus Eugene D. Commins passed away on September 26, 2015 after a brief illness. He was 83.

Born in New York City, Commins attended the Bronx High School of Science and Swarthmore College. Shortly after receiving his PhD from Columbia, and while serving as a research physicist there, he met Ulla Grip at the United Nations. They married a few months later in Stockholm and Commins soon learned to speak fluent Swedish. He joined Berkeley Physics in 1960 as an Assistant Professor and became Associate

Professor in 1965. He spent the 1967-1968 academic year as a guest professor at the University of Rome and in the process learned Italian and developed a love for that country. In 1969 he became Professor of Physics at Berkeley, serving as the chair of the Berkeley Physics Department from 1972-1974. In 2005, he was named Professor Emeritus.

Although he retired in 2001 he remained active in the department, continuing to teach and informally mentor Physics department students. That same year, colleagues, friends and former students gathered to honor him with the “ComminsFest Symposium.” The two-day event featured talks on Commins’ past and present scientific interests and highlighted his passion for music and art. For most of his life, Commins played violin and viola and was part of a regular string quartet. He was also an accomplished and prolific painter. The Symposium featured an array of distinguished speakers, most of whom traced their academic lineage to Commins. The conference proceedings, “Art and Symmetry in Experimental Physics” was published shortly thereafter. In 2014, Commins authored the book, Quantum Mechanics: an Experimentalist’s Approach. It was an outgrowth of lecture notes he developed while teaching Physics 221AB frequently between 1965 and 2010.

Professor Commins and a group of his students, including future Nobelist and U.S. Secretary of Energy Steven Chu, were among the first to observe atomic parity violation, a subtle effect of the fundamental weak interactions. These experiments confirmed the Weinberg-Salam-Glashow model which is at the core of what is now called “The Standard Model” and for which the three theorists were awarded the Nobel Prize in Physics in 1979.

A natural educator who was loved by his students, Commins was awarded UC Berkeley’s Distinguished Teaching award twice, first in 1963 and again in 1979. He was named a member of the National Academy of Sciences in 1987. In 2001, he was awarded the Berkeley Citation, which is given to individuals whose achievements exceed the standard of excellence in their fields. In 2005, he was the honoree of the Oersted Medal, by the American Association of Physics Teachers (AAPT). This award, named after Hans Christian Oersted, recognizes those who have had an outstanding, widespread, and lasting impact on the teaching of physics. In 2010, AAPT also awarded him the first J.D. Jackson Excellence in Graduate Education Award, a prestigious accolade given by the American Association of Physics Teachers (AAPT). Commins is also a Fellow of the American Association for the Advancement of Science (AAAS), a member of the American Academy of Arts and Sciences and a Fellow with the American Physical Society (APS).

“Eugene Commins was an outstanding professor and a recognized pioneer in the devel-opment of high precision experimental methods for measuring minuscule atomic effects of fundamental physical importance,” noted Steve Boggs, Berkeley Physics Department Chair. “He spent much of his career searching for the electric dipole moment of the electron – a measurement that has important bearing on the Standard Model of particle physics. His impact on our department, as a colleague, educator and mentor simply cannot be measured. He will be deeply missed.”

Commins is survived by his second wife Iris and son David, daughter-in-law Suzanne, and grandchildren Nicoletta and Luke. He is also survived by his sister Frances Bennett, nieces Jean Bennett, Nancy Bennett and Peggy Lynch Bennett.


“Eugene Commins was a great teacher, experimentalist, and mentor. When he lectured, it was as if you went on a little magical journey - he took your hand, showed you wonderful things, what's possible and what is not. And then brought you back and tucked you in.

In the laboratory, he was careful, soft-spoken, and gentle, and always the master at teaching-by-example. By not saying anything, he made me strive to do better every time.

I am proud to have known him and proud that he epitomizes, for me, the true physicist.”

–TUAN NGUYEN, THE COLLEGE OF NEW JERSEY PHYSICS

“You have to see what the student needs, have some intuition about what works, and most importantly, you need to pay attention to them. When it comes to my students, I’ve always been surprised by their brilliance and their ingenuity. They kept surpassing anything I expected... seeing a student become a scientist in their own right: that’s probably given me more satisfaction than anything else.”

–EUGENE D. COMMINS


Charles Hard Townes, a professor emeritus of physics at UC Berkeley who shared the 1964 Nobel Prize in Physics for his contri-bution to the invention of the laser and who pioneered the use of lasers in astronomy, died January 27, 2015 at the age of 99. Until last year, he visited campus daily, working either in his office in the physics department or at the Space Sciences Laboratory.

“The passing away of Professor Charles Townes marks the end of an era,” said astrophysicist Reinhard Genzel, a professor of physics at UC Berkeley and director of the Max Planck Institute for Extraterrestrial Physics. “He was one of the most important experimental physicists of the last century.”

“Charlie Townes had an enormous impact on physics and society in general,” said Steven Boggs, professor and chair Berkeley Physics. “His overwhelming dedication to science and personal commitment to remaining active in research was inspirational to all of us. Berkeley Physics has lost a true icon.”

INVENTION OF THE MASERTownes was 35 in the spring of 1951 when, seated on a park bench among blooming azaleas in Washington, DC, he was struck by the solution to a longstanding problem, how to create a pure beam of short-wavelength, high-frequency light.

That revelation – not much different from a religious revelation, Townes believed – eventually led to the first laser, a now ubiquitous device common in medicine, telecommunication, entertainment, and science.

His revelatory solution allowed him to separate excited from non-excited molecules and store them in a resonant cavity, so that when a microwave traveled through the gas, the molecules were stimulated to emit microwaves in step with one another: a coherent burst. He and his students built such a device using ammonia gas in 1954 and dubbed it a maser, for microwave amplification by stimulated emission of radiation.

In 1958, he and future Nobelist Arthur Schawlow conceived the idea of doing the same thing with optical light, using mirrors at the ends of a gas tube to amplify the light to get an “optical maser.”

Townes shared the 1964 Nobel Prize in Physics with two Russians, Aleksandr M. Prokhorov and Nicolai G. Basov, who independently came up with the idea for a maser.

SOUTHERN BORNBorn July 28, 1915, in Greenville, SC, Townes attended Furman University, graduating summa cum laude in 1935 at the age of 19 with a BS in physics and a BA in modern languages. He completed an MA in physics at Duke University in 1936 and obtained his PhD in 1939 from Caltech.

He joined the technical staff at Bell Labs in New Jersey, where he designed radar bombing systems through the war. He then began applying his expertise in microwaves to spectroscopy, which he foresaw as providing powerful new tools for probing the structure of atoms and molecules and for controlling light.


REMEMBERING CHARLES TOWNES Nobel laureate, laser pioneer, astrophysicist 1915-2014

Townes continued this work after accepting a faculty position at Columbia University in 1948, where he built the maser with graduate student James Gordon and post-doctoral researcher Herbert Zeiger. In 1961, after a brief tenure at the Institute for Defense Analyses, he was appointed provost and professor at MIT. In 1967 he was named a UC Professor-at-large based on the UC Berkeley campus.

Townes soon learned of plans by young professor William “Jack” Welch to build a short-wavelength radio telescope, and offered some of his startup funds to build a maser amplifier and microwave spectrometer so the telescope could be used to search for evidence of complex molecules in space. In 1968, Welch and Townes were the first to discover three-atom combinations – ammonia and water vapor – near the center of the Milky Way galaxy.

FIRST EVIDENCE FOR BLACK HOLE AT CENTER OF MILKY WAYTownes moved on to pioneer the field of infrared astronomy and precision infrared spectroscopy. He developed a novel infrared detector incorporating a precision CO2 laser, which made it easier to study this wavelength of light without contamination from hot sources all around us. His infrared studies of the center of the galaxy with Reinhard Genzel revealed in 1985 swirling gas clouds that could only be orbiting a massive object, presumably a black hole.

Townes subsequently built an interferometer, again using lasers, that combined infrared light collected by three separate telescopes into high-resolution images normally obtainable only with a much larger telescope. This Infrared Spatial Interferometer Array, housed in movable trailers at the Mt. Wilson observatory outside Los Angeles, can measure the diameters of stars that appear only as points of light in most telescopes.

Throughout his life, Townes maintained an interest in the intersection of science and religion. His seminal 1966 article, “The Convergence of Science and Religion,” established him as a unique voice – among scientists, in particular – seeking commonality between the two disciplines.“My own view is that, while science and religion may seem different, they have many similarities, and should interact and enlighten each other,” Townes wrote in a statement upon accepting the 2005 Templeton Prize.

A long list of awards and honors were bestowed upon Townes during his life. They include the National Medal of Science, honorary degrees from 25 universities, and esteemed awards from the National Academy of Sciences, the Optical Society of America, the Institute of Electrical and Electronics Engineers, the American Physical Society, the American Academy of Arts and Sciences, the Franklin Institute, NASA, and the Institute of Physics and the Physical Society (England). International honors also include the Wilhelm Exner Award (Austria) and the 1979 Niels Bohr International Gold Medal.

Townes is survived by his wife Frances, four daughters, six grandchildren, and two great grandchildren.Excerpted from an obituary written by Robert Sanders, Campus Media Relations



You were at Brookhaven and SUNY for 18 years. What prompted your move to Berkeley?For me personally, this is home. I was an undergraduate at Cal, grew up in Oakland and Alameda, and I still have family here. Professionally, I found the opportunity to become Director of the Nuclear Science Division at Berkeley Lab as well as professor on campus compelling and exciting.

Could you briefly describe your research at Brookhaven?Brookhaven Lab is a nuclear physics facility where heavy ions are collided at nearly the speed of light, to basically cook the nuclei of gold atoms into the quarks and gluons they’re made out of. We’re pretty sure we’re reaching a temperature of about 4 trillion degrees. This is the form in which matter existed shortly after the Big Bang, and we’re learning more and more about it.

What do you find most exciting about becoming Director of Nuclear Science at Berkeley Lab?Research here at Berkeley Lab is a very broad program that gives me a chance to look at the big picture, to explore areas beyond my own research. And it offers me the chance to contribute to strategic planning that will take nuclear physics – at Berkeley Lab and on campus – into the future.

What do you see coming up in the next decade?Nuclear physics is a very vibrant field right now. The nuclear physics commu-nity in the US is not only continuing to run big facilities but also building new ones. Construction of an electron facility is just now being finished at Jefferson National Laboratory in Virginia, and construction of a rare isotope facility at Michigan State University is underway.

Having these new facilities will bring us even closer to the kinds of

energies and conditions that existed in the very, very early universe. We’ll have the ability to collide beams of high-energy electrons with beams of high-energy protons and nuclei to figure out what happens in a really dense gas of gluons deep inside an atomic nucleus. The way gluons interact with one another is a lot more interesting, and a lot more complicated, than anybody thought. I see an exciting opportunity to build a research program for this at Berkeley.

In 1975, you were named a Foundation Scholar by the Achievement Rewards for College Scientists (ARCS) Foundation. This year, you became one of the first scientists to be inducted into the new ARCS Alumni Hall of Fame in honor of your “out-standing contributions to science and US competitiveness in STEM-based innovation.” What do these honors – just two among the many you’ve received over the years – mean for you, especially as a female physicist?The award from ARCS made a huge difference to me. There were few female role models in 1975, and the recognition was important. There still aren’t enough women in physics, so we need to encourage one another, and encourage young women to consider physics as a career. I enjoy helping ensure that women have opportunities to participate.

People sometimes have a stereo-typed view of scientists – nerdy physi-cists in particular – toiling away by themselves in a basement lab some-where. But the kind of physics experi-ments we do in big colliders is not like that at all. It’s very collaborative, very much a team science, and I think that’s an aspect of physics that appeals to women. It’s really exciting to do science with 500 or 1000 of your best friends around the world. n

FACULTY Q & A

Physics at Berkeley is pleased to announce the arrival this past January of new faculty member Barbara Jacak, a highly esteemed leader in the nuclear physics community in the United States. In addition to her appointment as Professor in the Department of Physics, she has taken on the post of Director of the Nuclear Science Division at Lawrence Berkeley National Laboratory and is a Faculty Senior Scientist at Berkeley Lab.

Jacak came to Berkeley from Brookhaven National Laboratory, where she has served as a leading member of the collaboration that built and operates the PHENIX detector, the largest collider experiment at Brookhaven. Her research has made significant contributions to our under-standing of how the universe evolved: she is one of the physicists responsible for the 2005 discovery of quark-gluon plasma (QGP), a type of matter com-posed of subatomic particles rather than atoms. QGP is postulated to be the type of matter that existed in the earliest moments of the universe, microseconds after the big Bang. For more on her distinguished career, see page 31.

In a recent interview, Jacak spoke about her career, her reasons for moving to Berkeley, and her thoughts on the future of nuclear physics.

Barbara Jacak, Nuclear Physicist


Lorraine Sadler (PhD ’06) has lever-aged the expertise she developed as a student at Berkeley into an exciting, successful professional life. Since receiving her PhD, she’s risen from Postdoctoral Scientist to a high-level post as Systems Analyst for Nuclear Security, all while working at Sandia National Laboratories in Livermore, California. And all while starting a family.

As an undergraduate researcher at Berkeley, Sadler worked with a team of particle physicists at Fermilab. For her PhD thesis, she explored Bose-Einstein condensates in professor Dan Stamper-Kurn’s atomic physics labora-tory. When she arrived at Sandia as a postdoc, her first project involved designing antineutrino detectors for national and international nuclear security.

“The flux of antineutrinos coming from a large nuclear reactor core can be used to detect whether the reactor is on or off,” she explains, “and to measure how much plutonium is being produced. When you turn off the reactor to switch out fuel, you have an inde-pendent check on how much plutonium should be recovered. You can make sure none is diverted for weapons use.”

Within a couple of years, she moved on to join and lead projects designed to find ways of detecting ionizing neutron or gamma radiation coming from

nuclear materials, with the goal of developing methods for identifying covert threats.

DESIGNING SECURITY POLICY About five years ago, soon after having her first child, Sadler decided she wanted to expand her horizons and become involved in more policy-driven work. She realized that what she enjoyed most about her job was using scientific expertise for the purpose of enhancing national security.

“I asked myself what kinds of unique skills I could bring to this work,” she recalls. Her answer was to step back from laboratory work and into a role that combines her physics background with her ability to explain, communicate, and make connections.

“I wanted to accomplish more than just figuring out how something could be done. I wanted to explain to decision makers – people who might not be scientists, or who might not have depth of knowledge in all the scientific areas involved in a particular security protocol – why money should be invested in one technology or method-ology over another.”

Security threats fall into several broad categories: radiological, nuclear, chemical, and biological, as well as energy and cyber security. Sadler focuses on the first two, looking for ways to deter threats involving radio-active materials or nuclear weapons. “A lot of fundamental physics is involved in these areas,” she reports, “and having an inherent understand-ing of the physics is really important.”

She and her colleagues look for answers to broad questions posed by government officials and others. What threats are of concern? How are law enforcement agencies addressing these concerns, and what is their level of awareness?

Addressing a problem like the potential smuggling of radioactive substances involves more than devel-

oping prevention technologies, Sadler says. “You have to think from the point of view not only of people who are looking to do harm, but also of law enforcement. If the equipment or pro-tocol you provide isn’t used because enforcers don’t understand the mission, even if you developed the best possible technical solution, you’ve failed. You have to think beyond the science.”

WORKING FOR DIVERSITY AND INCLUSIONSadler is passionate about encouraging young scientists, especially women and underrepresented minorities, to find their best career niche. In addition to recruiting recent graduates for Sandia, she works with the California Alliance, a consortium of universities and national laboratories that aims to increase diversity in math, physical sciences, computer science, engineering, and related disciplines. “The Alliance supports outstanding candidates and gives them the opportunity to explore career ideas,” Sadler notes.

As the mother of two young daughters, Sadler appreciates Sandia’s support for family life. Moms can take maternity leave without fear that it will affect their opportunities for advancement. And flexible scheduling enables her to work four days a week, with a day off to spend with her kids.

Working at Sandia has encouraged her to identify and use her strengths. “When I started here, I didn’t know the job I have now even existed,” Sadler says. “Broad, high level, systems think-ing is one of my strengths, along with the ability to communicate with scien-tists, politicians, law enforcement, program managers, subject matter experts. Putting these skills together has been such a positive thing. I really enjoy what I do.” n

ALUMNA PROFILE

Lorraine Sadler Uses Physics to Protect the Nation


DEPARTMENT NEWS

Marvin L. Cohen Interaction Center DebutsEmeritus professor Marvin Cohen has been extolled as one of the most influential researchers in physics. Fellow Berkeley physicist Steven Louie has called him the pillar of the Berkeley physics department. Cohen is a condensed matter theorist renowned for developing computational tools that describe the quantum properties of materials – materials that already exist, as well as those that are still theoretical. He has explained the behavior of many materials critical to the electronics industry, from silicon and superconductors to graphene, fullerenes, and boron-nitride nanotubes.

Cohen’s long list of awards include the 2001 National Medal of Science, the 2011 Dickson Prize in Science from Carnegie Mellon University, and the 2013 Von Hippell Award from the Materials Research Society. He is currently University Professor of Physics and Professor in the Graduate School on campus, and a senior faculty scientist at Lawrence Berkeley National Laboratory.

On March 6, colleagues, current and former students, staff, and donors gathered to celebrate the unveiling of the new Marvin L. Cohen Interaction Center on the top floor of Birge Hall. Designed to promote meaningful exchanges among condensed matter faculty and students, the new center features comfortable chairs, translucent dry-erase boards, an espresso machine, and plenty of natural light. “We can write on these walls, sit in these chairs, drink coffee and talk,” Cohen said at the unveiling. “And hopefully great ideas will be generated here.”

The Summer 2015 issue of California Magazine features an article on Cohen, written by Sabin Russell, that summarizes some of Cohen’s many accomplishments and describes his emphasis on taking a collaborative approach to scientific endeavors.

“We can write on these walls, sit in these chairs, drink coffee and talk. And hopefully great ideas will be generated here.”

—MARVIN COHEN

(Top) An architectural rendering of the Cohen Interaction Center. (Second from top) Physics alumn and former Cohen student Jihsoon Ihm (l) with Marvin Cohen. (Third from top, l-r) Supporters of the new center included Frank and Lee Battat, Steve and Arlene Krieger, and Marianne and Herbert Friedman, pictured with Suzy Cohen. (Bottom) The room includes a specially commissioned painting, “The Theorist’s Tools,” by William Glass, architect.


DEPARTMENT NEWS

HONORS FOR COHEN AND SHENTwo of Berkeley’s most esteemed condensed matter physicists, Marvin L. Cohen and Y. Ron Shen, turned 80 years old in March. To celebrate, both have been honored with new areas named after them and with a birthday symposium highlighting their many contributions to science. Both scientists joined the physics faculty in 1964 and are credited with helping build Berkeley into a major research center in theoretical and experimental condensed matter physics. Though officially retired, they are still active in research and teaching.

Their birthday event, “The Special Symposium on Structures and Electrons in Molecules, Surfaces and Reduced Dimensional States”, took place March 7 in LeConte Hall. The agenda included several invited talks that were open to the public, with titles ranging from “Two-Dimensional Materials Beyond Graphene” to “Ten Ways to Design a Material.”

The current Reading Room (top) has been an iconic feature in Physics for 60 years. Part of its fame involves the custom of sending paper airplanes into the ceiling. An artist’s rendering shows the new Physics Reading Room and Collaboration Center (bottom), which will offer study space with state-of-the-art amenities for hard-working students, including wifi, plenty of electrical outlets, flexible seating, and black boards and white boards for collaborative problem solving.

New Physics Reading Room and Collaboration Center Set to OpenTransformation of the almost-60-year-old Undergraduate Reading Room in LeConte Hall is now underway. When complete, it will emerge as the new Physics Reading Room and Collaboration Center, with a design that incorporates advanced technology - including wifi and an abundance of electrical outlets - and reflects the collaborative nature of today’s scientific endeavors. It will boast more study space, with long tables for problem-solving and discussion.

The remodeled space will include the Professor Harry H. Bingham Room, dedicated by inaugural donor Carolyn Gee and Henry Blauvelt. Bingham, who passed away in 1994, was an inspirational teacher and physicist. It will also include the Y. Ron Shen Common Room, a

conference area designed to provide a supportive environment for one-on-one discussions as well as group meetings, encour-aging the kinds of interactions that lead to scientific discovery and understanding. It is named after Professor Emeritus Y. Ron Shen, a highly acclaimed experimentalist in condensed matter and materials science, especially renowned for his work in nonlinear optics. He is credited with single-handedly developing the technologies needed to apply nonlinear optics to the study of surfaces and interfaces of all types, from metals and water to semiconductors, magnets, and exotic systems such as molecules adsorbed on surfaces.

Construction of the new Reading Room is now underway, with completion expected by early 2016.


An Opportunity to Say ‘Thanks!’Student recipients of the department’s scholarships and fellowships turned out in full force in January to extend a special ‘thank you’ to the donors, alums and benefactors who have made their awards possible. Graduate student posters were also on display, and guests enjoyed special music by Berkeley Physics students Sam Kohn and Celeste Carruth. The evening also offered students an oppor-tunity to engage in discussions with a number of Emeritus Berkeley Physics faculty. “We are so

grateful for the strong support of our alums and friends,” said Steve Boggs, chair. “Our students loved meeting the individual donors who have made their awards possible. The event also provided our guests with the opportunity to hear more about our research and the specific interests our students have. It was a great night!”

DEPARTMENT NEWS

A Bench and Courtyard to Honor that Nobel Moment

The venerable oak tree that graced the courtyard between LeConte and Birge Halls for the past 75 years or more was lost to rain and wind last December. The tree watched over innumerable student gatherings through the years, and served as an iconic witness to the history of physics at Berkeley.

Charles Townes could see the oak tree from his Birge Hall office window. His death on January 27, so soon after it fell, evoked a compelling feeling of connection between these two elders of the department.

In response, a new funding cam-paign has been launched to not only replace the tree, but also commemorate the epiphany Townes famously experi-enced on a park bench among spring flowers – the revelatory moment that led to his 1964 Nobel Prize and development of the laser.

The Senior Class of 2016 and the Department of Physics plans to honor that moment by placing a symbolic bench in the courtyard, surrounded by a grove of trees. It’s the first time a graduating class has chosen to organize and provide a gift back to the depart-ment. Once fully funded, a plaque will share the story of Townes’ revelation and encourage Berkeley students to sit and contemplate how they too might change the world. And perhaps even win a Nobel Prize.

To learn more about the Townes Bench and Courtyard opportunity contact Berkeley Physics.

New Faculty Chair Honors Eugene ComminsA new endowed Chair has been created in honor of the late Eugene Commins, Berkeley physics professor emeritus, who passed away in September. The Eugene D. Commins Chair in Experimental Physics was inspired by Berkeley alumnus and Nobel laureate Steve Chu, who says he considers himself Commins’s ‘prodigal son.’ In his Nobel prize biography, Chu writes that Commins had “an uncanny ability to bring out the best in all his students.” Chu is the new endowment’s lead donor.

Commins is recognized as a pioneer in the development of experimental methods for measuring atomic effects that are extremely small and difficult to detect. He spent much of his career searching for the electric dipole moment of the electron – a measurement that has important bearing on the Standard Model of particle physics. In 2002, the year after he retired, Commins and graduate student Chris Regan published the results of an experiment that set the most stringent limit yet obtained for the size of the electron’s electric dipole moment. “It was a good, hard, experiment,” Commins said, at the time. “I’m very proud of it.”

For information about how to contribute to the endowment fund for the Eugene D. Commins Chair in Experimental Physics, contact Berkeley Physics.

Students Leigh Martin and Eric Parsonnet with Professors Emeritus Howard Shugart and Erwin Hahn

More than 50 students attended the Physics Philanthropy Thank You event.


Campbell Hall DedicatedOn February 12, faculty, friends, donors and staff gathered to dedicate the rebuilt Campbell Hall. The original building, completed in 1959, and named for the astronomer and 10th UC president William Wallace Campbell, was demolished in 2012 to make way for a seismically robust structure. The new space provides offices and state-of-the-art research facilities for astronomy and physics as well as ‘Cosmology Commons’ – a satellite space for the Berkeley Center for Cosmological Physics (BCCP). The new Center for Integrated Precision and Quantum Measurement is in the basement.

An open-air bridge joins Campbell Hall with the third floor of LeConte Hall, offering a physical link that helps foster the already vibrant relationships among astronomers, astrophysicists, physicists and cosmologists on campus.

“New Nobel prizes will be won because of this building,” predicted Mark Richards, professor of earth and planetary science and former executive dean of the College of Letters and Science. The project was made possible, in part, with grants from the National Institute of Standards and Technology (NIST) and the Heising Simons FoundationCONTRIBUTED IN PART BY ROBERT SANDERS, CAMPUS MEDIA RELATIONS

(Top) The official ribbon was cut on the Campbell hall banner by Astronomy Chair Imke de Pater, Mark Heising of the Heising-Simons Foundation, Carl Williams of NIST, Berkeley Chancellor Nicholas Dirks, Math and Physical Sciences Dean Frances Hellman, Liz Simons of the Heising-Simons Foundation, former Letters and sciences executive Dean Mark Richards, former Assemblywoman Nancy Skinner, and Physics Chair Steve Boggs. (Middle) A new telescope, built by Dick Treffers, adorns the sixth floor balcony. (Bottom left, l-r) Inaugural donor Betty Helmholz and Maria Hjelm, Senior Development Director for Letters and Sciences. (Bottom right, l-r) Michael Diestel of NIST and Berkeley Project Manager Allan Palmer tour one of the basement labs.

DEPARTMENT NEWS


DEPARTMENT NEWS

New Experimental Particle Physics CenterUC Berkeley has a new research center devoted to breakthrough discoveries in experimental particle physics. The Berkeley Experimental Particle Physics Center (BEPP) is creating a new hub for innovation for developing instrumentation, computing, and analytical and numerical methodologies that will be key to continued successes in this field.

In partnership with its sister centers – the Berkeley Center for Theoretical Physics and the Berkeley Center for Cosmological Physics – BEPP capitalizes on and leverages existing Berkeley efforts to address fundamental questions about the nature of matter and energy and the evolution of the universe. BEPP also fosters new connections across scientific and engineering disciplines on campus, at Lawrence Berkeley National Laboratory (Berkeley Lab), and in industry.

“The Berkeley Experimental Particle Physics Center offers an outstanding opportunity to make connections among related areas of study, from supersymmetry to dark matter,” says Marjorie Shapiro, Berkeley Physics Professor and Director of the Center.

BEPP activities reach even into the realm of cultural preservation. Carl Haber, BEPP member and Berkeley Lab physicist, was inspired by particle physics instrumentation to develop a technology for preserving and restoring sound recordings that are too fragile for conventional playback. See related story on page 36.

BEPP members are involved in a wide variety of research projects, including continuing work with the ATLAS collaboration at the LHC and its search for physics beyond the Standard Model, the underground LUX experiment’s search for dark matter, and neutrino physics experiments at Daya Bay in China and CUORE in Italy.

For more information about BEPP and opportunities to help support its research activities, visit bepp.berkeley.edu.

BERKELEYEXPERIMENTALPARTICLEPHYSICS

BERKELEYEXPERIMENTALPARTICLEPHYSICS

BERKELEY EXPERIMENTALPARTICLE PHYSICS

Annual BCTP Tahoe Summit

Berkeley Center for Theoretical Physics (BCTP) faculty, researchers, post docs, students and their families gathered in September at the Lake Tahoe home of Doug Tuttle (’71) and his wife Lynn Brantley. The annual summit, now in its fifth year, offers an opportunity for interactions, creative thinking and collaboration for the theory community. Tuttle and Brantley are founding donors to the BCTP and offer an annual fellowship to one theory student each year. This year’s student fellow is Jason Sean Weinberg.


Popular CalDay lectures included “The Physics of Bikes” with Professor Joel Fajans (top) and “Fun with Physics” with Professor Bob Jacobsen (second from top). Hands-on displays and interactive exhibits were enjoyed by guests of all ages. Those who took the “Physics Passport Tour” – a journey through the entire department, including the student machine shop – were awarded with a Physics Honorary Degree (Ph.D) upon completion (above).

Cal Day 2015This year’s Cal Day festivities took place on Saturday April 18. As usual, this annual UC Berkeley open house included a variety of fascinating activities and exhibits offered by the Department of Physics.

Physics students guided visitors on tours of the Student Machine Shop, the Donald A. Glaser Advanced Lab and the Dark Matter Search Lab in LeConte and through the new Quantum Nanoelectronics Lab in Campbell Hall. Students also treated visitors to Hands-On Physics interac-tive exhibits on the second floor of LeConte Hall.

Jaw-dropping demos, from amazing to simply spectacular, were the focus of Fun with Physics lectures from professor Bob Jacobsen. Professor Joel Fajans taught The Physics of Bikes and Professor Uros Seljak provided the latest information on dark matter, dark energy, and the origins of structure in the universe.

Cal Day 2016 is scheduled for April 16.

DEPARTMENT NEWS


Faculty Honors and AwardsJames Analytis was one of 44 scien-tists nationwide selected to receive a 2015 Early Career Research Grant from the US Department of Energy. He was also awarded a 2015 Sloan Research Fellowship, an honor given to ‘rising stars and the next generation of scientific leaders.’

Stuart Bale was named a Fellow of the American Physical Society.

Steve Boggs was named a Fellow of the American Physical Society.

Carlos Bustamante was elected to the American Academy of Arts and Sciences.

John Clarke was elected to the American Academy of Arts and Sciences.

Frances Hellman was selected as the recipient for the 2015 Joe Shapiro Award. This award is presented annually to those individuals whose work and service to the community promote a positive and lasting impact. This award recognizes individuals who display exemplary characteristics of humani-tarianism, leadership, and vision. Awards are based upon an individual’s pursuit of a better life for all humankind.

Reinhard Genzel recently received three awards: the Great Cross of Merit with Star; The Paris Observatory Award; and the Harvey Prize from the Israel Institute of Technology, which “recog-nizes breakthroughs in science and technology and have contributed to the progress of humanity.”

Naomi Ginsberg was awarded a 2015 Sloan Research Fellowship, an honor given to ‘rising stars and the next generation of scientific leaders.’

Oskar Hallatschek received the Simons Investigator Award from the Simons Foundation for his work in large-scale patterns and the influence of spatial structure on biological processes.

Barbara Jacak was selected for the Advancing Science in America (ARCS) Hall of Fame. This honor is given to those who have made outstanding contributions to the advancement of science and to US competitiveness in STEM-based innovation.

Steven Louie has been selected to receive the 2015 Materials Theory Award from the Materials Research Society “for his

seminal contributions to the develop-ment of ab initio methods for, and the elucidation of, many-electron effects in electronic excitations and optical prop-erties of solids and nanostructures.“

Holger Müller was awarded a Bakar Fellowship, an honor given to early career scientists whose research shows

commercial promise.

Irfan Siddiqi was named a Fellow of the American Physical Society.

Ashvin Vishwanath was named a 2015 Simons Investigator. The award recognizes him as “a leading

quantum condensed matter physicist, known for his work on quantum phase transitions beyond the Landau-Wilson-Fisher paradigm, his recent theoretical prediction of Weyl semi-metals, and his generalizations of the topological insulator concept beyond the single-particle approximation.”

Ahmet Yildiz received an American Society for Cell Biology-Gibco Emerging Leader Prize “for advancing the filed of single-molecule biophysics, including his work on understanding the mechanism of the protein motor dynein and maintenance of chromo-some telomeres.”

Shank Wins Fermi Award

Charles (Chuck) Shank was named by President Barack Obama as a recipi-ent of the Enrico Fermi Award “for the seminal devel-

opment of ultrafast lasers and their application in many areas of scientific research, for visionary leadership of national scientific and engineering research communities, and for exem-plary service supporting the National Laboratory complex.” Shank served as Director of Lawrence Berkeley National Laboratory from 1989-2004 and is an Emeritus Professor of Physics at Berkeley. The Fermi Award is one of the federal government’s oldest and most prestigious awards for scientific achievement.

New FacultyHernan Garcia came to Berkeley in January to begin joint appointments as Assistant Professor in the Departments of

Physics and of Molecular and Cell Biology. He received a Bachelor’s Degree in Physics from the University of Buenos Aires, Argentina in 2003, and a PhD in Physics from Caltech in 2011. From 2011 to 2014 he did postdoctoral work in the Physics Department at Princeton University as a Dicke Fellow and as a Burroughs Wellcome Fund Career Award at the Scientific Interface Fellow. He is a co-author of Physical Biology of the Cell, published in 2013.

FACULTY NEWS


Garcia’s research focuses on the events during cell development that determine how a single cell develops into a multicellular organism with many different cell types. “We now know,” Garcia explains, “that the decisions cells make during development are not so much based on which genes to express, but rather on when, where, and how to express them. Despite advances in determining the identities of the molecules that mediate these decisions, we are still incapable of pre-dicting how simple physical parameters such as the number, position, and affinity of binding sites for these mole-cules on the DNA determine develop-mental fates.”

His research group uses the fruit fly, a classic model for embryonic development, along with a combination of new technologies, quantitative experiments, and statistical mechanics. The overall goal is to achieve a predic-tive understanding of developmental programs that control biological size, shape, and function. (See p 11)

Barbara Jacak joined the Berkeley faculty as Professor of Physics in January. She also became Director of the Nuclear Science

Division and a Faculty Senior Scientist at Lawrence Berkeley National Laboratory.

Jacak completed her undergraduate studies at UC Berkeley, and received her PhD at Michigan State University where her advisor was David K. Scott. On graduating from MSU, she received an Oppenheimer Fellowship at Los Alamos National Laboratory and remained on the staff there until January 1997, when she joined the fac-ulty at SUNY Stony Brook as Professor of Physics. She was promoted to Distinguished Professor in 2008.

Her research focuses on experi-mental study of quark gluon plasma. This plasma is formed in relativistic

heavy ion collisions where nuclei are heated to trillions of degrees and quarks are no longer confined in hadrons. Jacak was one of the founding members of the PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC), and was spokesperson of the experiment from 2007 until 2012. Before joining PHENIX, she was active in the CERN heavy ion program as a member of the Helios and E844 Collaborations.

Jacak has been very active in the development of the national nuclear physics program and served on the Long Range Plan working groups in 1995, 2001, and 2006. She is a Fellow of the NAS, APS and AAAS, and is a member of the National Academy of Sciences. (See p 22)

Daniel McKinsey joined the faculty as Assistant Professor of Physics and the Georgia Lee Distinguished

Chair in July. He received a BS in Physics with highest honors at the University of Michigan in 1995. His PhD was awarded by Harvard University in 2002, with a thesis on the magnetic trapping, storage, and detec-tion of ultracold neutrons in superflu-id helium. His postdoctoral research took place at Princeton University, and in 2003 he joined the Yale University physics department, where he was promoted to Professor in 2014.

McKinsey is a leader in the field of direct searches for dark matter interac-tions, and serves as co-spokesperson of the LUX experiment. He was awarded a Packard Fellowship in Science and Engineering and an Alfred P. Sloan Research Fellowship, and served on the 2013-2014 Particle Physics Project Prioritization Panel.

McKinsey’s research centers on non-accelerator particle physics, parti-cle astrophysics, and low-temperature physics. In particular, he works on the development, construction, and opera-

tion of new detectors using liquefied noble gases, which are useful in look-ing for physics beyond the Standard Model. Applications include the search for dark matter interactions with ordi-nary matter, searches for neutrinoless double beta decay, and the measure-ment of the low-energy solar neutrino flux.

He is especially interested in the physics of the response of liquefied noble gases to particle interactions, the calibration of these detectors so as to understand their response, and the overall development of new experi-mental techniques for reaching sensi-tivity to extremely rare, low-energy particle interactions.

Matt Pyle joined the faculty in July as Assistant Professor of Physics and the Michael M. Garland Distinguished

Chair. He received a BS in Physics in 2001 and BE in Aerospace Engineering in 2002 from the University of Notre Dame, and a PhD in Physics from Stanford University in 2012. He subse-quently crossed the bay to become a post-doctoral research fellow at Berkeley.

Theoretical physi-cist Norman Ying Yao, currently a Miller Fellow working in professor Ashvin Vishwanath’s

research group, will join the Berkeley physics faculty in 2017. Yao’s research interests range from quantum optics and atomic physics to condensed matter theory, topological order, and quantum information. He received a PhD in physics from Harvard in 2014.

FACULTY NEWS


Perlmutter Accepts 2015 Breakthrough PrizeIn recognition of their 1998 discovery of the accelerating expansion of the universe, Berkeley’s Supernova Cosmology Project team and its leader, Nobel laureate Saul Perlmutter, were named co-winners of the 2015 Breakthrough Prize in Fundamental Physics. They shared the prize with the

High-Z Supernova Search team, led by fellow Nobelists Brian Schmidt and Adam Riess. Perlmutter, Riess, and Schmidt shared the 2011 Nobel Prize in Physics for their

teams’ discoveries. Perlmutter is a Berkeley Professor of Physics and co-director of the Berkeley Center for Cosmological Physics. Riess, now with Johns Hopkins University and the Space Telescope Science Institute, is a former UC Berkeley postdoc. Schmidt is with Australian National University. All 51 members of both teams shared equally in the $3 million prize.

The annual Breakthrough Prizes are given in three categories – physics, life sciences, and mathematics – to “celebrate scientists and generate excitement about the pursuit of science as a career.”

Celebrities and Hollywood luminaries, including actors Benedict Cumberbatch and Cameron Diaz, presented the awards at a star-studded gala in Silicon Valley on Nov. 9, 2014. The ceremonies were produced and directed by Emmy Award-winning Don Mischer Productions, simulcast on Discovery Channel and Science Channel in the United States, and later televised globally on BBC World News. Winners in all three categories were further celebrated during symposia held at Stanford University on Nov. 10.

The Breakthrough Prizes are sponsored by Google co-founder Sergey Brin and his wife, Anne Wojcicki, a founder of the genetics company 23andMe; Alibaba Group founder Jack Ma and his wife, Cathy Zhang; Russian entrepreneur and venture capitalist Yuri Milner and his wife, Julia; and Facebook founder Mark Zuckerberg and his wife, Priscilla Chan.

Falcone Elected APS Vice President

Berkeley physics professor Roger Falcone has been elected Vice President of the American Physical Society (APS)

for 2016. Falcone joined the Berkeley physics faculty in 1983 and has been Director of the Advanced Light Source (ALS) at Lawrence Berkeley National Lab since 2006. He served as Chair of the Physics Department from 1995-2000.

In his research, Falcone uses ultrafast pulses of x-rays to study dynamic phenomena in condensed matter, molecular, and atomic physics. These ultrafast pulses, measured in femtoseconds – one millionth of a bil-lionth of a second – represent the times-cale in which chemical bonds are formed or broken, or materials transi-tion from one phase to another. Falcone helped establish the Ultrafast X-Ray Facility at the ALS to expand research opportunities and experimental capa-bilities in the field.

Falcone takes a keen interest in science education. He was founding co-director of California Teach, UC Berkeley›s outreach for K-12 education aimed at producing 1,000 new science and math teachers each year for California classrooms. Currently, he chairs the Faculty Advisory Committee for the Lawrence Hall of Science, Berkeley's public science center and resource for K-12 education.

In his APS candidate's statement, Falcone said, “The breadth of physics extends from searching for deeper understanding of the organizing principles of the universe to meeting societal needs, with the APS acting as a community-driven structure that helps scientists address these areas. APS can strengthen the collective impact of physicists, and improve the educational, industrial, private, and government institutions within which science is carried out.”

Saul Perlmutter (center) accepted the 2015 Breakthrough Prize in Physics with Brian Schmidt (left), and Adam Riess. (Reuters)

Murayama Addresses UN on Science and PeaceThe link between science and peace was the topic of remarks given by Hitoshi Murayama at a United Nations gathering celebrating the 60th anniversary of CERN, the European Organization for Nuclear Research. Murayama gave the keynote address, titled “Science for Peace and Development Today and Tomorrow.” He is a professor of physics at UC Berkeley and director of the Kavli Institute for Physics and Mathematics at the University of Tokyo.

“I firmly believe that basic scientific research is a true peacemaker for human-kind,” he said. “The awe of the beautiful universe makes differences in cultures, languages, colors, genders, religions, and ideologies simply disappear.”

Held at UN headquarters in New York on October 20, 2014, the celebration highlighted the role science plays in peaceful collaboration, innovation, and develop-ment. “CERN embodies this idea that basic science unifies people from all nations,” Murayama said. “Thousands of people from friendly or warring nations come to CERN and build amazing scientific instruments together.”Contributed in part by Robert Sanders, Campus Media Relations

FACULTY NEWS


PHYSICS IN THE MEDIA

Photo: C.-L. Chiu/COSI/NASA

A Singularly Unfeminine Profession - One Woman’s Journey in Physicsby Mary K. Gaillard, World Scientific Publishing Co, 2015. isbn-13: 978-9814644228 isbn-10: 9814644226

In 1981 Mary K. Gaillard became the first woman on the physics faculty at the University of California at Berkeley. Her career as a theo-retical physicist spanned the

period from the inception in the late 1960s and early 1970s of what is now known as the Standard Model of particle physics and its experimental confirmation, culminating with the discovery of the Higgs particle in 2012.

In A Singularly Unfeminine Profession Gaillard recounts her experi-ences as a woman in a very male-domi-nated field, while tracing the develop-ment of the Standard Model as she witnessed it and participated in it. The generally nurturing environment of her childhood and college years, as well as experiences as an undergraduate in particle physics laboratories and as a graduate student at Columbia University, which cemented her passion for particle physics, left her unprepared for the difficulties that she confronted as a second year graduate student in Paris, and later at CERN, another particle physics laboratory near Geneva, Switzerland.

The development of the Standard Model, as well as attempts to go beyond it, and aspects of early universe physics, are described through the lens of Gaillard’s own work, in language written for a lay audience.

In September, Gaillard greeted students, friends, and colleagues in 375 LeConte to talk about and sign the book.

NASA launches next-generation scientific balloonSuper-pressure technology could keep gamma-ray telescope aloft for 100 days or more around Antarctica.Alexandra Witze, Nature News, 29 December 2014

NASA has launched its most ambitious scientific balloon ever. On 28 December at 21:16 London time, technicians inflated and released a 532,000-cubic-metre aero-static balloon from near McMurdo Station in Antarctica. It is the biggest test yet of a ‘super-pressure’ design that enables a helium balloon to stay aloft much longer than conventional balloons.

...More time aloft equals more science. The super-pressure balloon is carrying a gamma-ray telescope to hunt for high-energy photons streaming from the cos-mos. Known as the Compton Spectrometer and Imager (COSI), it can detect where in the sky the rays are coming from, and thus begin to unravel various astronomical mysteries.

COSI is the first science payload designed from scratch to take advantage of NASA’s super-pressure technology, says team leader Steven Boggs, an astrophysicist at the University of California, Berkeley. [COSI’s] predecessors used liquid nitrogen to cool themselves, but nitrogen runs out in less than 10 days. COSI carries a mechanical cooler so has nothing to run out of.



Photo by University of California, Lawrence Berkeley National Laboratory, Roy Kaltschmidt, photographer

Berkeley Physics Professor Beate Heinemann, a spokesperson for the ATLAS experiment at the Large Hadron Collider, spoke at an international symposium on lepton-photon interactions in Ljuljana, Slovenia in August.

Daya Bay places new limit on sterile neutrinosby Kathryn Jepsen, Symmetry, 1 Oct 2014

The Daya Bay Reactor Neutrino Experiment ... has narrowed the region in which the most elusive kind of neutrino, the sterile neutrino, might exist.

...“We have multiple reactors as well as detectors,” says co-leader of the Daya Bay experiment Kam-Biu Luk of Lawrence Berkeley National Laboratory and the University of California, Berkeley. “As a result we are in a very good position to search for sterile neutrinos, particularly in a region that hasn’t been explored before.”

... Neutrinos are known to oscillate between three types. The question Daya Bay set out to answer was whether there is a fourth type that mixes with the other three. Sterile neutrinos have yet to be discovered, possibly because they interact with matter less than any other type of neutrino – a characteristic that has made them candidate dark matter particles. ... Daya Bay scientists ruled out the exis-tence of these neutrinos at the lowest masses ever probed.

“We have no idea where the sterile neutrino is hiding, if it exists,” Luk says. “Therefore it is very important to have many types of experiments search in different regions.”

Collider hopes for a Super Restartby Jonathan Amos, BBC News, Feb 14, 2015

A senior researcher at the Large Hadron Collider says a new particle could be detected this year that is even more exciting than the Higgs boson.

The accelerator is due to come back online in March after an upgrade that has given it a big boost in energy.

This could force the first so-called supersymmetric particle to appear in the machine, with the most likely candidate being the gluino.

Its detection would give scientists direct pointers to “dark matter”. And that would be a big opening into some of the remaining mysteries of the universe.

“It could be as early as this year. Summer may be a bit hard but late summer maybe, if we’re really lucky,” said [Berkeley physics] Prof Beate Heinemann, who is a spokeswoman for the Atlas experiment, one of the big particle detectors at the LHC.

“We hope that we’re just now at this threshold that we’re finding another world, like antimatter for instance. We found antimatter in the beginning of the last century. Maybe we’ll find now supersymmetric matter.”

...”This would rock the world,” said Prof Heinemann. “For me, it’s more exciting than the Higgs.”


POLARBEAR Sniffs Out Cosmic Clues About The Universe, Dark Matter And NeutrinosBrid-Aine Parnell, Forbes, 22 Oct 2014

Scientists have made the most sensitive and precise measurements ever of the polarisation of the cosmic microwave background... This polarisation is the orientation of the cosmic microwave background radiation’s electric field. Dark matter twists the polarisation into a ‘B-mode’ pattern as the light passes through the gravitational fields of mas-sive objects, and this pattern has been successfully isolated by POLARBEAR.

“We made the first demonstration that you can isolate a pure gravitational lensing B-mode on the sky,” said Adrian Lee, POLARBEAR principal investigator and UC Berkeley professor of physics and faculty scientist at Lawrence Berkeley National Laboratory (LBNL). “Also, we have shown you can measure the basic signal that will enable very sensitive searches for neutrino mass and the evolution of dark energy.”

... The collaboration hopes that this technique will help them discover when dark energy, the mysterious force that accelerated the expansion of the Universe, started to dominate and then overwhelm gravity...

Three POLARBEAR patches overlaid on a full-sky 857 GHz intensity map (Planck Collaboration 2013a). Image: POLARBEAR collaboration

Volcanoes may have helped asteroid kill dinosaursby David Perlman, SFGate, 2 May 2015

...Led by UC Berkeley geologist Mark Richards [former Dean of Physical Sciences at Berkeley], the group proposed that when the giant asteroid hit Earth about 66 million years ago, its impact sent such violent tremors through the planet’s crust that it set off a wave of volcanic eruptions half a world away.

Those eruptions, known as flood basalts, “were among the largest in the history of the planet, and would have buried all of California a mile deep in lava,” Richards said.

But the asteroid’s impact itself, which gouged an immense crater in the ocean floor off Mexico’s Yucatan Peninsula, remains the “main cause” of the event that drove most of the world’s dinosaurs and three-quarters of all other life on Earth to extinction, Richards said.

Both events could have raised such immense plumes of toxic gases that they would have darkened Earth, lowered global temperatures, and made it impossible for most life to exist. The result was one of the world’s frequent mass extinctions.

...The theory that the asteroid impact caused that mass extinction was instantly controversial when it was first advanced by the noted Berkeley geologist Walter Alvarez and his father, the late [UC Berkeley] physicist Luis Alvarez, 25 years ago.

The asteroid impact that caused mass extinctions 66 million years ago may have set off a cascade of volcanic eruptions.

NASA telescope details lopsided star explosionby Brooks Hays, UPI, 7 May 2015

NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) has confirmed that an exploded star was demolished in a lopsided fash-ion. The new data – detailed in the latest issue of Science – is evidence that the star, named 1987A, died a violent death known as a Type II or core-collapse supernova. Type II supernovae are asymmetrical by nature.

...NuSTAR’s observations confirm the core-collapse charac-

terization. The telescopic array was able to plot the scattering of titanium-44 more precisely than ever before. Titanium-44 is a radioactive material isolated to the core of the intense explosion.

...“Stars are spherical objects, but apparently the process by which they die causes their cores to be turbulent, boiling and sloshing around in the seconds before their demise,” explained lead author Steve Boggs, a researcher at the University of California, Berkeley. “We are learning that this sloshing leads to asymmetrical explosions.”

There is more research to come. As the evolution of the smoldering supernova continues, the explosion will be revealed in new ways. “In some ways, it is as if 1987A is still exploding in front of our eyes,” said Boggs.

Data from NuSTAR confirm the asymmetrical explosion of a Type II supernova 1987A. (ESA/Hubble & NASA)



A New Theory to Explain the Higgs MassNatalie Wolchover, Quanta, 27 May 2015

...Three physicists who have been collaborating in the San Francisco Bay Area over the past year have devised a new solution to a mystery that has beleaguered their field for more than 30 years.

... Despite its sway over the motion of stars and galaxies, the force of gravity is hundreds of millions of trillions of trillions of times weaker than magne-tism and the other microscopic forces of nature.

... The new proposal offers a possible way forward. The trio is “super excited,” said David Kaplan, 46, a theoretical particle physicist from Johns Hopkins University in Baltimore, Md., who developed the model during a West Coast sabbatical with Peter Graham, 35, of Stanford University and Surjeet Rajendran, 32, of the University of California, Berkeley.

Their solution traces the hierarchy between gravity and the other funda-mental forces back to the explosive birth of the cosmos, when, their model suggests, two variables that were evolving in tandem suddenly dead-locked. At that instant, a hypothetical particle called the “axion” locked the Higgs boson into its present-day mass, far below the scale of gravity.

The axion has appeared in theo-retical equations since 1977 and is deemed likely to exist. Yet no one, until now, noticed that axions could be what the trio calls “relaxions,” solving the hierarchy problem by “relaxing” the value of the Higgs mass. “This just seems like a pretty simple possibility,” Rajendran said. “We’re not standing on our heads to do something crazy here. It just wants to work.”

LHC physicists preserve Native American voicesSarah Charley, Symmetry, 10 June 2015

Physicists are using LHC [Large Hadron Collider] detector technology to retrieve Native American music from old recordings.

Berkeley physicist Carl Haber [a member of the Physics Department’s Berkeley Experimental Particle Physics Center] listened in astonishment as the first notes of the 1950s hit “Goodnight Irene” played through his computer. “It was one of those moments you remember your whole life,” Haber says.

The song came from an old record, but no needle traced its grooves. Haber wasn’t listening to the record; he was listening to an image of the record, which then-postdoc Vitaliy Fadeyev had produced by scanning it with a high-powered microscope. A set of mathematical algorithms then interpreted the trenches embossed on the record’s surface and translated them into sounds.

... Haber says, “if you could take a recording and turn it into a picture, then you could extract the information by using these mathematical approaches we were applying to our physics research.”

This summer, Haber and Cornell are partnering with the UC Berkeley Linguistics Department and the UC Berkeley Libraries to start the biggest project yet – scanning and extracting sound from the 2700 wax cylinders stored in the University of California Phoebe Hearst Museum of Anthropology that document the culture, language and music of dozens of Native American tribes from California.

Ethnographer Frances Densmore with Blackfoot chief, Mountain Chief, during a 1916 phonograph recording session for the Bureau of American Ethnology. (Wikimedia Commons)



Graphene Used To Create Extremely Efficient Ultrasonic Speakers And MicrophonesAndrea Alfano, Tech Times, 7 July 2015

Developing microphones and speakers that can process ultrasound has been a challenge in the field of communica-tion technology research, but a new graphene-based design allows them to do so extremely efficiently, according to a paper published in the journal Proceedings of the National Academy of Sciences. This advance represents one of the early steps toward commer-cially-viable graphene-based devices.

“There’s a lot of talk about using graphene in electronics and small nanoscale devices, but they’re all a ways away,” the study’s senior author, Alex Zettl of the University of California, Berkeley said in a statement. “The microphone and loudspeaker are some of the closest devices to commercial viability, because we’ve worked out how to make the graphene and mount it, and it’s easy to scale up.”

...They found that using graphene as the diaphragm material made it pos-sible for the speakers and microphones to operate across an incredibly broad range of frequencies, including ultra-sound. The benefits of using graphene are in part due to the fact that it is extremely thin and lightweight.

The one atom-thick wonder material known as graphene could be incorporated into speakers and microphones to enable them to process sounds far below and above the limits of human hearing [including the ultrasound frequencies used for echolocation by bats]. (Photo: Bill Tyne Flickr)

From the big bang to cosmic vibrations, Grateful Dead’s Mickey Hart plays the rhythm of the universeInterview conducted by correspondent Mike Cerre, PBS, 2 July 2015

Mickey Hart, a well-known drummer for the Grateful Dead, has collaborated with astrophysicists on music that reflects the origins of the universe, and with neuro-scientists to figure out how music stimulates different parts of damaged brains. ...

Mickey Hart: The universe is made up of vibrations. I have been very interested in sonifying the universe, the cosmos, the sun, the Big Bang, taking those radiations from telescopes, radio telescopes, and turning that radiation into sound, which I make music out of and compose with, in the macro, and now in the micro with the brain waves, heart rhythms, DNA, stem cells. All of these have a sound. And so we take these sounds in and we embed them in the music. ...

The moment of creation, beginning of time and space, when the blank page of the universe exploded and it created the stars, the planets, black holes, pulsars, supernovas, this was the beginning of time and space, and then us. And then we are still now toying with this rhythmic stimuli that was created 13.7 billion years ago.

George Smoot, University of California, Berkeley: What is needed is someone who is artistic to hear these sounds and be inspired by them and turn them into something that is really pleasing for people to hear.

Mike Cerre: Astrophysicist George Smoot earned a Nobel Prize for his work in charting the origins of what many believe to be the beginning of creation, with the Big Bang. He’s also a longtime Dead Head.

Mickey Hart: He can show me waveforms of the first million years and all that. And that’s really great. But as soon as I see it, I said, give me those waveforms, George. And let’s see what they sound like. And let’s dance to those things. And George said, yes.

Mike Cerre: With the help of the University of California at Berkeley’s super-computer, Smoot’s team converted light wave traces from the Big Bang into sound waves for Mickey to work with.

Mickey Hart: Because it’s very inharmonic. It’s very dense. There’s a lot of collisions up there, and there’s a lot of bumps and grinds and pulses and stuff and noise, which you wouldn’t call music. But I take it, and I make it into what the human ear would call music, so we can enjoy it.



Dark matter behaves like well-known particle, new theory suggestsShayne Jacopian, RedOrbit, 23 July 2015

A new theory suggests that dark matter acts very much like sub-atomic particles known to the sci-entific community since the 1930s – pions. ... An inter-national group of researchers has proposed that dark matter is very similar to pions –

the subatomic particles that hold atomic nuclei together.... Their findings were published in Physical Review Letters on July 10.

Hitoshi Murayama, Professor of Physics at the University of California, Berkeley, and the Director of the Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo... explains: “We have seen this kind of particle before. It has the same properties – same type of mass, the same type of interactions, in the same type of theory of strong interactions that gave forth the ordinary pions.”

The theory suggests that dark matter likely interacts with itself within galaxies or galaxy clusters, possibly modifying predicted mass distributions.... The theory will soon be tested in a series of experiment utilizing the Large Hadron Collider, the SuperKEKB, and the SHIP experiment.

Artist’s impression of dark matter distribution. Left image assumes conventional dark matter theories, where dark matter would be highly peaked in small area in galaxy center. Right image assumes SIMPs, where dark matter in galaxy would spread out from the center. (NASA, Space Telescope Science Inst., Kavli IPMU)

How Jon Stewart made people laugh while teaching them about climate change Camille von Kaenel, E&E reporter, ClimateWire: Tuesday, August 11, 2015

A bowl full of ice cubes, talking almonds, and many, many puns: These were some of Jon Stewart’s weapons in his war against climate change denial-ism. His quips made people laugh, but they also got them thinking.

After 16 years on Comedy Central’s satirical news program “The Daily Show,” which he left Thursday, Stewart will be remembered by loyal viewers for his biting political commen-tary – but he also offered refreshingly critical science coverage. That could have shaped how his audience viewed climate change, according to a new study released Friday. The paper joins a growing body of research into “the Stewart/Colbert effect,” or the influ-ence of news satire.

Paul Brewer, a communications professor at the University of Delaware, and Jessica McKnight, a doctoral student, published their most recent paper in Science Communication. They showed two groups of clips of Stewart and Stephen Colbert on “The Colbert Report” talking about a climate study. A third control group saw an unrelated clip.

In the “Daily Show” clip, aired in October 2011, Stewart goes over new research by University of California, Berkeley, physics professor Richard Muller, whose biggest private funders were the oil-rich Koch brothers.

“Whoa, global warming is real. Did not see that coming,” Stewart jested. “The Earth is getting warmer. Or, judging by this graphic, getting more embarrassed.”

The groups who saw the satirical news clips were slightly more likely to believe in climate change after the experiment, the study found.

Scientists Created the World’s Quietest Gas to Hear Quantum EffectsJamie Condlifee, Gizmodo, 5 Aug 2015

If you want to hear something very quiet, you need to reduce the ambient volume of your surroundings. For quantum physicists, though, that meant creating the world’s quietest gas. That’s exactly what a team from the University of California, Berkeley, has done, cooling a gas to a billionth of a degree above absolute zero. It’s not the coldest temperature ever recorded, but their set-up does result in the lowest entropy ever measured—another way of saying that it’s the quietest state ever achieved.

... “Temperature generates something like a constant rumble of sound in the gas, and the entropy is like a count of how many sound-wave excitations remain,” [Berkeley physics professor] Dan Stamper-Kurn, one of the researchers, told PhysOrg. “The colder a gas becomes, the less entropy it has and the quieter it is.”

... they expect to be able to use it to understand how quantum magnets and high-temperature superconductors work. “When all is quiet and all is still,” muses Stamper-Kurn to PhysOrg, “one might discern the subtle music of many-body quantum mechanics.”



Is this the only universe?Laura Dattaro, Symmetry, 28 July 2015

...there may be infinitely many universes, bubbling into existence and growing exponentially. It’s a theory known as the multiverse.

One of the best pieces of evidence for the multiverse was first discovered in 1998, when physicists realized that the universe was expanding at ever increasing speed. They dubbed the force behind this acceleration dark energy. The value of its energy density, also known as the cosmological

constant, is bizarrely tiny: 120 orders of magnitude smaller than theory says it should be.

For decades, physicists have sought an explanation for this disparity. The best one they’ve come up with so far, says Yasunori Nomura, a theoretical physicist at the University of California, Berkeley, is that it’s only small in our universe. There may be other universes where the number takes a different value, and it is only here that the rate of expansion is just right to form galaxies and stars and planets where people like us can observe it. “Only if this vacuum energy stayed to a very special value will we exist,” Nomura says. “There are no good other theories to understand why we observe this specific value.”

... Einstein’s general theory of relativity implies that our universe may have a “shape.” It could be either positively curved, like a sphere, or negatively curved, like a saddle. A negatively curved universe would be strong evidence of a multiverse, Nomura says. And a positively curved universe would show that there’s something wrong with our current theory of the multiverse, while not necessarily proving there’s only one.

... Nomura predicts that within the next few decades, measurements of the universe’s shape could be precise enough to detect a slight curvature. That would give physicists new evidence about the nature of the multiverse. “In fact, this evidence will be reasonably strong since we do not know any other theory which may naturally lead to a nonzero curvature at a level observable in the universe,” Nomura says.

World’s highest-perfor-mance single-molecule diode createdColin Jeffrey, Gizmag, 3 August 2015

As electronics miniaturization heads towards a theoretical physical limit in the tens of nanometers, new methods of manufacturing are required to produce transistors, diodes, and other funda-mental electronic components. ... a group of researchers from Berkeley Lab and Columbia University claims to have created the highest-performing, single-molecule diode ever made, which is said to be 50 times better in performance and efficiency than anything previously produced.

“... we were able to create a diode that resulted in a rectification ratio, the ratio of forward to reverse current at fixed voltage, in excess of 200, which is a record for single-molecule devices,” said Jeffrey Neaton, director of the Berkeley Lab’s Molecular Foundry and professor [of physics] at the University of California Berkeley.

...The combined Berkeley Lab-Columbia University research team is convinced that the way they have managed to produce a single-molecule diode sets the benchmark for future nonlinear nanoscale device tuning and development, with applications above and beyond just junctions of single- molecule components.

... said professor Neaton. “Beyond devices, these tiny molecular circuits are petri dishes for revealing and designing new routes to charge and energy flow at the nanoscale. ... we’re just at the tip of the iceberg with what we can understand and control at these small length scales.”

Diagram of the molecular junction that functions as a diode, allowing current to flow in one direction only

Hunting the Higgs - The Inside Story of the ATLAS Experiment at the Large Hadron Colliderby Claudia Marcelloni and Colin Barras, with Science Editor Beate Heinemann, 64 pages, Papadakis Dist A C, 2014. isbn 978-1-906506-37-7

Berkeley particle physicist Beate Heinemann served as science editor for Hunting the Higgs, a companion volume that updates a larger book, The Atlas Experiment, Exploring the Mystery of Matter, which was published before the Higgs boson was discovered at the Large Hadron Collider.

Hunting the Higgs contains detailed, full-color photo-graphs of the machinery and the scientists who contributed to the discovery. The book’s publication coincided with a major exhibition called “Collider” put on by the Science Museum in London in 2013.



STUDENT AFFAIRS

First Senior Class Gift CampaignDedicated senior class officers (l-r) Kathryn Chu, Kelly Backes, Ivan Aguilar, Isabella Urdinaran, and Gauri Pravin, (not pictured) have launched a philanthropy campaign to create a bench in the Physics Courtyard between LeConte and Birge Halls in honor of late Professor Emeritus Charles Townes. See related story on page 28.

The Big GiveAnastasia Bizyaeva, president of the Berkeley chapter of the Society of Physics Students (SPS) and Alejandro Ruiz, President of IGEN Spectrum represented two of the student clubs that participated in last November’s Big Give campaign.

The one-day online and social media fundraising oppor-tunity also provided direct donor support for the Society of Women in the Physical Sciences (SWPS), the Physics Grad Student Association, Compass, the Physics Social Club and the Career Development Initiative for the Physical Sciences (CDIPS). This year’s event is set for November 19 with the theme, ‘Think Bigger!

Annual Student Poster SessionsIt would not be Fall without the traditional graduate student poster session and the opportunity for newly admitted Berkeley Physics students to review research opportunities. In Spring, it’s the undergraduates’ turn and a chance to showcase what they’ve learned. Undergrad (top photo) Kevin Nuckolls and Grad student (middle photo) Mollie Schwartz were among the participants.


Each summer, three gifted under-graduate students receive Segré Internships which allow them to conduct experimental research in the Donald A. Glaser Advanced Lab. This year Eric Parsonnet, Talya Sindel, and Edward Zhang will be among the first students to work with a brand new experiment recently installed in the lab.

The Atomic Force Microscope (AFM) is used to image objects on the scale of ang-stroms to a few microns through the use of physical scanning rather than optics, like conven-tional electron microscopes. The basic mechanism of the AFM is a vibrating probe tip with laser feedback. A cantilever is attached to the tip, which interacts with the surface. A laser is reflected off of the cantilever and into a detector. Software is used to center the beam in the detector, and this creates a reference zero. A sample is then placed on the stage underneath the tip, and scanned over. Variations in height of the sample will translate to vertical movement on the

cantilever, which perturbs the position of the reflected laser in the detector. Atomic force microscopy is an essential tool used in many applications.

Parsonnet, Sindel, and Zhang join a tradition of students who have shared the Segrè intern honors through the years – all made possible through the generosity of Arlene and Doug Giancoli.

Segrè Summer Interns 2014

STUDENT AFFAIRS

Edward Zhang (left), Talya Sindel and Eric Parsonnet in the Donald A. Glaser Advanced Lab.

L. Jackson Laslett ScholarshipVarun Raj Benjamin SheffLeo Steinmetz S.M. “Jack” and Avish Holmes Olsen ScholarshipHan Aung Wenyuan Bao Gina Belair Peter Dotti Brianna Grado-White Isidore Pomerantz ScholarshipKevin BabbEmil BarkovichJoseph DeRoseFangda JiaTian KangSkylar KerznerCaroline KimJihoon KimRea KolblGary Li

Berkeley Physics Undergraduate Research Scholars (BPURS)Fall 2014Andy ChuAlexander ChuangChistropher DockNathan HendelSeth HirschYi JinRamin KhajehAlison KimPhilip LuKevin NuckollsJared ReitenBen SheffManuel SilvaNikhil SthalekarWilliam TokumaruXinkang WangKak Wong

Brian TimarSaavanth Velury

Kevin Hayakawa Brady Huynh Matthew McAllister Charles Paul

Sio Chong LoDevlin MalloryStuart SherwinMaria SimanovskaiaHaoyu SunAaron TranXinkang WangKevin YuYisi Zhu

Spring 2015Alexander ChuangDhruv DesaiOmer HazonNathan HendelSeth HirschPhilip LuYinchuan LvKevin NuckollsJared ReitenBen SheffManuel SilvaWilliam TokumaruAditya Venkatramani

PHYSICS UNDERGRADUATE SCHOLARSHIPS


STUDENT AFFAIRS

FALL 2014Natania Antler Adviser: Irfan SiddiqiSuperconducting Nanobridge SQUID Magnetometer for Spin SensingPeter Brian Battaglino Adviser: Mike DeWeeseMinimum Probability Flow Learning: A New Method for Fitting Probabilistic ModelsJeffrey Scott Birenbaum Adviser: John ClarkeThe C-shunt Flu Qubit: a New Generation of Superconducting Flux QuibitJoshua Burkart Adviser: Eliot QuataertTides in Close Binary SystemsTom Griffin Adviser: Petr HořavaLifshitz HolographyAustin J. Hedeman Adviser: Robert LittlejohnSemiclassical Analysis of Fundamental Amplitudes in Loop Quantum GravityGeena Kim Adviser: Holger MüllerA New Laser Cooling Method for Lithium Atom InterferometryHanhan Li Advisers: K. Birgitta Whaley and Irfan SiddiqiCircuit-QED and Quantum Feedback ControlG. Edward Marti Adviser: Dan Stamper-KurnScalar and Spinor Excitations in a Ferromagnetic Bose-Einstein CondensateAna Krasimirova OvcharovaAdviser: Marjorie ShapiroMeasurement of the top quark pair differential cross-section at high top quark transverse momentum in 8 TeV proton-proton collision data collected with the ATLAS detector at the LHCChristopher Lee Smallwood Adviser: Alessandra LanzaraTime- and Angle-resolved Photoemission Studies of Cuprate SuperconductorsChukman So Adviser: Jonathan WurteleAntiproton and positron dynamics in antihydrogen production

Physics Ph.D DegreesNational Science Foundation FellowshipAlex AndersonHalleh BalchEmma DowdParker FagreliusBrendan FolieJustin GerberSatcher HsiehHilary JacksTrinity JoshiSylvia LewinGilbert LopezSarah MarzenMargaret McCarterRobert McGeheeChris MogniNityan NairKelsey Oliver-MalloryAbi PolinDiana QiuVinay RamaseshCaroline SofiattiKelly SwansonErik UrbanJaime VarelaHertz FellowshipDaniel LecoanetKatelin SchutzMollie SchwartzAdam Stooke National Defense Science and Engineering Graduate FellowshipWill BerdanierSteven DrapchoAndrew EddinsJonathan KohlerChris OlundAlejandro RuizSophie WeberDillon WongDOE (Dept. of Energy)Hannah KlionFabio SanchesKwanjeong Educational FoundationJihwan OhNSERC - Canadian FellowshipMichael FangCarolyn KieransAmelia Earhart FellowshipNicole Duncan

Lars Commins Memorial Award in Experimental PhysicsSydney SchrepplerBrantley Tuttle Tahoe AwardJason Sean WeinbergUniversity of California FellowshipJennet DickinsonSamantha DixonIrina EneKodiak MurphyHelmholz Gateway FellowshipVetri VelanErwin Hahn FellowshipVir BulchandaniMary and Andrew Sessler FellowshipVijay NarayanHeising-Simons FellowshipNicholas SalzettaVictor F. Lenzen FellowshipStorm WeinerJackson C. Koo AwardAidin Fathalizadeh

PHYSICS PRIZES AND AWARDSDepartment CitationAditya Vignesh Venkatramani Student Service AwardsKevin Torres GrosvenorSydney Frances SchrepplerAlvaro Alejandro Loya Villalpando

Outstanding Graduate Student Instructor AwardsCeleste Carruth Chien-I Chiang Derrek Alan Coleman Eric Allen Copenhaver Eric McVoy Dodds Arielle Little Yi-Chuan Lu Robert Stephen McGehee Jr.Mudassir Moosa Alexander Peter Povilus Jeffrey Clinton Prouty Daniel Joseph Rizzo Zachary Thomas Stone

GRADUATE STUDENT FELLOWSHIPS


STUDENT AFFAIRS

Alexander Sood Adviser: Beate HeinemannEvidence for the production of two W bosons with the same electric charge and two jets in 20.3 fb−1 of pp collisions at s√=8 TeV using the ATLAS detectorBryan SteinbachAdviser: Adrian LeeMeasurement of the B-mode power spectrum with POLAR BEARLiang Zheng TanAdviser: Steven LouieElectronic and vibrational properties of two-dimensional materials constructed from graphene and molecular componentsYang Wang Adviser: Michael CrommieScanning Tunneling Microscopy Study of Graphene Electronic NanostructuresSteven Joseph Weber Adviser: Irfan SiddiqiQuantum Trajectories of a Superconducting QubitBenjamin Westbrook Adviser: Adrian LeeStudies of the Cosmos Using Spiderweb Absorber Transition Edge SensorMichael P. Zaletel Adviser: Joel MooreExact Tensor Network Ansatz for Strongly Interacting Systems

SPRING 2015Aaron Joe Bradley Adviser: Michael CrommieLocal Probe Investigation of the Electronic Structure of Two-Dimensional Thin Film Materials Using Low Temperature Scanning Tunneling Microscopy and Spectroscopy with a Focus on Molecular Beam Epitaxially Grown Metallic and Semiconducting Transition Metal DichalcogenidesJacquelyn Kay BrosamerAdviser: Marjorie ShapiroMeasurement of additional jets produced in top quark events at 8 TeV with the ATLAS detectorRobert Najem Clarke Adviser: Marjorie ShapiroA Search for Lepton Flavor Violating Decays of the 125 GeV Higgs Boson to Hadronically Decaying Tau Leptons and Muons or Electrons with the ATLAS Detector at the LHCOnur Ergen Adviser: Alex ZettlApplication of Two Dimensional Layer Materials in Energy Conversion and Storage DevicesAidin Fathalizadeh Adviser: Alex ZettlSynthesis, Characterization, and Fabrication of Boron Nitride and Carbon Nanomaterials and their ApplicationsKevin Torres Grosvenor Adviser: Petr HořavaAspects of Lifshitz Quantum Field TheoriesBrian Quinn Henning Adviser: Hitoshi MurayamaEffective field theories and precision Higgs physics

Jason Shih An Horng Adviser: Feng WangUnderstanding Graphene Physics for Optical SensingLong Ju Adviser: Feng WangOptical Spectroscopy of Two Dimensional Graphene and Boron NitridePauli Mark Kehayias Adviser: Dmitry BudkerExploring Basic Properties and Applications of Nitrogen-Vacancy Color Centers in DiamondJonghwan Kim Adviser: Feng WangUnderstanding light-matter interactions in atomically thin 2D materialXiaochuan Lu Adviser: Hitoshi MurayamaAspects of Particle Physics beyond the Standard ModelChristopher Stewart Macklin Adviser: Irfan SiddiqiQuantum Feedback and Traveling-wave Parametric Amplification in Superconducting CircuitsSandra Christine Miarecki Advisers: Spencer Klein and Marjorie ShapiroEarth vs. Neutrinos: measuring the total muon-neutrino-to- nucleon cross section at ultra-high energies through differential Earth absorption of muon neutrinos from cosmic rays using the IceCube DetectorFrancisco Javier Monsalve Adviser: Holger MüllerTesting Lorentz Invariance with a Birefringent CavityJonathan Loren Ouellet Adviser: Yury KolomenskyThe Search for Neutrinoless Double Beta Decay in Tellurium 130 with CUORE-0Alexander Peter Povilus Adviser: Joel FajansCyclotron-Cavity Mode Resonant Cooling in Single Component Electron PlasmasCory Drew Schillaci Adviser: Wick HaxtonEffective Interactions for Few-Body PhysicsSydney Frances Schreppler Adviser: Dan Stamper-KurnQuantum Measurement with Atomic Cavity OptomechanicsDerek Wayne Vigil Fowler Adviser: Steven LouieQuasiparticle scattering, lifetimes, and spectra from first principlesHaruki Watanabe Adviser: Ashvin VishwanathSpontaneous Symmetry Breaking in Nonrelativistic SystemsJianbo Xie Adviser: Edgar Knobloch Chimera States in Phase-coupled oscillators


COMMENCEMENT

The Class of 2015Clear skies and bright sunshine was the order of the day on May 20 as students from Berkeley Physics and Astronomy filed into Zellerbach Auditorium for the 2015 Commencement.

The joint ceremony featured keynote speaker Gibor Basri, Vice Chancellor, Equity and Inclusion and Professor of Astronomy, and remarks from Steve Boggs, Chair of the Department of Physics and Frances Hellman, Dean of Math and Physical Sciences. Peter Dotti, a double major in both Applied Mathematics and Physics was the student speaker.

For the 2014-2015 academic year, Bachelor degrees were awarded to 114 students, Masters degrees to 36 students and PhDs conferred upon 38 individuals.

For the 2014-2015 academic year, Bachelor degrees were awarded to 114 students, Masters degrees to 36 students and PhDs conferred upon 38 individuals.

Berkeley Physics kicked off the day with a special awards brunch in LeConte Hall. Twenty graduate and undergraduate awards were presented, including:

Student Service Awards were given to Kevin Torres Grosvenor, Sydney Frances Schreppler and Alvaro Alejandro Loya Villalpando.

Outstanding Graduate Student Instructor Awards were given to Celeste Carruth, Chien-I Chiang, Derrek Alan Coleman, Eric Allen Copenhaver, Eric McVoy Dodds, Arielle Little, Yi-Chuan Lu, Robert Stephen McGehee Jr,. Mudassir Moosa, Alexander Peter Povilus, Jeffrey Clinton Prouty, Daniel Joseph Rizzo Zachary and Thomas Stone

The Lars Commins award, an annual citation to the most deserving graduate student in experimental physics, was given to Sydney Schreppler. The award is named after Lars Commins, son of the late Berkeley Physics Professor Emeritus Eugene Commins. Lars was an accomplished engineer with a deep interest in experimental physics. The award in his honor was created in 2004 as a lasting tribute and to help perpetuate the strong tradition of experimental physics at Berkeley.

The Jackson C. Koo Award in Condensed Matter Physics was awarded to Aidin Fathalizadeh. Created by Koo’s widow Rose, to honor Jackson’s legacy, it is awarded to a high achieving graduate student in Condensed Matter Physics.

Aditya Vignesh Venkatramani was awarded the department’s top Citation, which is given to the most outstanding undergraduate student in scholarship and research.

Student award winners (pictured with chair Steve Boggs) enjoyed a pre-commencement brunch.


COMMENCEMENT

(Top left, l-r) Department Chair Steve Boggs, Xiaochuan Lu, Hanhan Li, Jianbo Xie, Long Ju and Professor Emeritus Marvin Cohen. (Top right) Peter Dotti, student speaker. (Middle left) Omnur Ergen, PhD candidate (Middle right, l-r) Undergrads Eli Mizrachi, Nicole Lewis, Joanne Szornel and Kevin Gutowski (Bottom, l-r) Jon Ouelett, Sydney Schreppler, Jackie Brosamer, Brian Henning, Cory Schillaci and Aaron Bradley were among the 38 students conferred PhD degrees.

Berkeley is a place where the brightest minds from across the globe come together to explore, ask questions and improve the world


CLASS NOTES

’89Mike Mann BS ’89, is the Distinguished Professor of Meteorology and Director of the Earth System Science Center at Penn State University. His research focuses on understanding climate variability and human-caused climate change. He was selected by Scientific American as one of the fifty leading visionaries in science and tech-nology in 2002. He was organizing committee chair for the National Academy of Sciences Frontiers of Science in 2003 and contributed to the award of the 2007 Nobel Peace Prize with other IPCC lead authors. He was awarded the Hans Oeschger Medal of the European Geosciences Union in 2012 and the National Conservation Achievement Award of the National Wildlife Federation in 2013. He made Bloomberg News’ list of fifty most influential people in 2013. In 2014, he received the Friend of the Planet award from the National Center for Science Education. He is Fellow of both the American Geophysical Union and American Meteorological Society, and has authored more than 170 publications, including two books, Dire Predictions and The Hockey Stick and the Climate Wars.

’99Andreas Birkedal, MA ’99, PhD ’03 is Vice President of Quantitative Research at Two Sigma Investments. His research focuses on medium to high frequency domestic equities trading. His work has encompassed price forecasting, strategy optimization, investigations of tail risk events, research tool development as well as production monitoring and maintenance. Prior to joining Two Sigma, he was an Associate Director in Equities at Eladian Partners (2011-2012).In this role, he conducted statistical research on financial data to develop domestic equities aggressive and market-making strategies, as well as developing, implementing and improving high fre-

quency equity and ETF price forecasts.Prior to Eladian, he served as a Quantitative Analyst at D.E. Shaw & Co. (2006-2011), where he also focused on medium to high frequency domestic equities trading.

IN MEMORY

David Bentley Fenneman (1935-2014)David Bentley Fenneman (BA ’59) died January 19, 2014 at his home in Fredericksburg, Virginia. He was 79. Born January 25, 1935 in San Pedro, California, Fenneman received his BA in Physics from Berkeley after a tour of duty in the United States Army. He received his MS and PhD in Physics from the University of Illinois at Urbana-Champaign.

Fenneman was a career civil service employee of the United States Navy, working first at the Naval Air Weapons Station at China Lake, California, and retiring from the Naval Surface Warfare Center at Dahlgren, Virginia. While at the Navy, he held patents for a hypersonic gas laser, a laser pile cutter, a self-compressing supersonic flow device, an apparatus for and method of intrinsic time constant of liquids and a liquid-filled variable capacitor.

After his retirement from the Navy, he was especially interested in the physics of plucked strings. He is survived by one sister and one daughter.

David L. Fischer (1928-2015)David Fischer (PhD ’56) died April 19 after a brief illness. He is survived by his wife of 59 years, Zoe Fischer, three

children, five grandchildren, two sisters, and one brother. Fischer was a nuclear physicist and later recognized as a nucle-ar engineer, and he was a longtime member of the American Nuclear Society.

Born June 7, 1928, Fischer excelled in mathematics and the sciences. The youngest of five children, he graduated

in 1946 from Chaffee High School in Upland, California where his father was the principal. After two years at Chaffee Community College he trans-ferred to UC Berkeley where he gradu-ated in 1950. While in Graduate School at UC Berkeley he worked as a teaching assistant in Physics and as a Physicist in the Radiation Laboratory before receiving his PhD in Nuclear Physics in 1956. Professor Owen Chamberlain oversaw his thesis, “Experiments on Interference and Polarization in Nucleon-Nucleon Scattering.”

While at UC Berkeley, Fischer was an active member of the Acacia Fraternity. He remained in close contact with his fraternity brothers and his family was honored to have some of them travel long distance to attend a party in honor of Fischer’s life this summer.

From 1956-1988 Fischer made sig-nificant contributions to the Nuclear Energy Department at General Electric in San Jose, California. During this time, he managed large groups of engi-neers working primarily with nuclear fuel development for the nuclear power plants built by GE. Upon retirement in 1988, Fischer was the Manager of Core Nuclear Design, Nuclear Fuel Engineering Department at GE.

Fischer was one of the pioneers who helped General Electric and the country in providing an indigenous, alternative form of energy to produce electricity. He was one of the original physicists doing nuclear calculations for Dresden 1. His professionalism and objectiveness always stood out, and his influence on Boiling Water Reactor (BWR) design, automated fuel designs, and the GE Nuclear Engineering character past and pres-ent was profound.

He was held in very high regard during his 32-year career at GE and was remembered for his outstanding technical capabilities, standard of excellence, and unlimited patience. He set the bar for honest evaluations and straight talk among several genera-


tions (professionally) of respected nuclear engineers at GE. When asked to describe him, whether a co-worker, family or friend, words that repeat include integrity, fairness, honesty, humility, kindness, unselfishness, and more. Fischer had the ability to encourage and bring out the best in all who had the privilege of knowing him.

Some of the specific contributions that Fischer made to nuclear engineering included:• Inventing application of gadolinia

burnable poisons to nuclear fuel, which revolutionized the process and thereafter became routine in all BWRs worldwide.

• Pioneering advance technology applications to fuel manufacturing quality, especially non-destructive enrichment measurements;

• Innovating management of applied core analysis – integrating procedural discipline, modern computers and highly talented people into a world-class, highly productive capability.

An Eagle Scout who loved the out-doors, when he retired in 1988 from General Electric, Fischer and his wife moved to Lake Tahoe where he espe-cially loved hiking in the high Sierra. He was also an avid tennis player and snow skier. In his retirement he consulted, tutored at-risk high school students, and volunteered as a court appointed special advocate for neglected and abused children with C.A.S.A.

Donations in his name may be made to the Physics Reading Room and Collaboration Center.

John R. Hiskes (1928-2015)John R. Hiskes (BA/MA/Ph.D ’60) passed away on February 19, 2015 after complica-tions following a recent illness. He was 87.

He was born in Chicago, Illinois to John and Alice Hiskes. After high school, he served in the Coast Guard as an electronic technician, attending

to lighthouses up and down the West Coast. This ignited a soon to be deep love for all things California, travel and adventure.

In 1951, He married his wife Dolores and they moved to California. John enrolled at UC Berkeley and received his BA, MA, and Ph.D in Theoretical Physics in 1951, 1952, and 1960. Following graduation, he moved to Livermore, where he pursued a career in atomic and molecular physics and magnetic fusion at Lawrence Livermore National Lab. This involved numerous trips to Europe and the Soviet Union and a year-long assignment in Abingdon, England.

Having discovered the charms of Yosemite, John launched a campaign to climb all the high points of the park. The campaign directed him to other explorations and together with his son Grant, he wrote The Discovery of Yosemite. Copies of this book now reside in the Bancroft Library at UC Berkeley and in the California Historical Society’s Library in San Francisco. An astronomer by interest, John hand-built two telescopes – a task that involved grinding his own lenses. After retiring from LLNL in 1991, his passions extended further to history, jogging, archeology, and religion – including forming a loosely knit group called the ‘Livermore Theological Society.’

He is survived by his wife of 64 years, Dolores, brother Donald and sister in law Ruth and his children, Robin Hiskes Caproni (Christopher) and John Grant Hiskes and grandchildren Connor and Austenne.

Judith (Judy) Goldhaber Judy Goldhaber, wife of the late physicist Gerson Goldhaber, passed away on May 26 following a hemor-rhagic stroke she suf-

fered on May 14. She was 81.Judy was a science writer for

Lawrence Berkeley National Laboratory (Berkeley Lab) for 35 years,

during which she wrote more than a thousand articles about Berkeley Lab research. “Explaining scientific research so that the public can under-stand and appreciate its value is what science writers do,” said Lynn Yarris of Berkeley Lab’s Communications Dept., “and no one ever did it better. With her long mane of flaming red hair, she was one of the most recog-nizable figures on the Hill, along with her husband of 41 years, renowned physicist Gerson Goldhaber, who died in 2010.”

The couple collaborated on two books of poems, Sonnets from Aesop and Sarah Laughed: Sonnets from Genesis. Gerson was the artist who created the illustrations, Judy was the poet. She was also a playwright who wrote the book and lyrics for a musical about Stephen Hawking, entitled “Falling Through a Hole in the Air,” that was produced and performed at San Francisco City College. Her collab-orator on that and other musical projects was Berkeley Lab astrophysicist Carl Pennypacker.

Judy joined the Public Information Department of the Lawrence Berkeley Laboratory (LBL) in 1961, where she met Gerson. They were married in 1969. In the summer of 1976, she oversaw the launching of the LBL Newsmagazine, a quarterly journal that chronicled the scientific accomplishments of the laboratory and the people behind those accom-plishments, and subsequently served as its editor-in-chief. The publication “broke the mold for institutional jour-nals in its broad reader-friendly approach,” Yarris said.

Judy is survived by two daugh-ters, four grandsons, and a step-son and his wife. She was buried next to Gerson at Gan Shalom Cemetery in Briones, CA. Services were held on June 2.Contributed in part by Lynn Yarris, Berkeley Lab Communications Dept.

CLASS NOTES

Seventy-five years ago, the 1939 Nobel Prize in Physics was awarded

to Ernest Orlando Lawrence during a special ceremony at Wheeler Hall on the Berkeley campus. On Feb. 29, 1940, the Swedish consul general, left, presented the prize, with UC President Robert Sproul looking on. Lawrence could not journey to Sweden to receive the award because steamship travel had become too dangerous – World War II was imminent and Hitler’s submarine wolf packs were prowling the Atlantic.

(Photo courtesy of Lawrence Berkeley Lab)

CALENDAR OF EVENTSTuesday January 19 Start of Spring Semester 2016

Monday February 8 J. Robert Oppenheimer Lecture in PhysicsCharles KaneWalter H. and Leonore C. Annenberg Professor in the Natural Science, University of PennsylvaniaChevron Auditorium at I-House

Saturday April 16 Cal Day 20169:00 a.m. to 4:00 p.m. berkeley.edu/calday

Sunday May 15 Physics-Astronomy CommencementZellerbach Auditorium

On the Cover: Illustration of a myosin protein "walking" along a myosin fiber inside a cell, from the research of Berkeley biophysicist Ahmet Yildiz. (PrecisionGraphics.com)

Physics at Berkeley 2015Published annually by the Department of PhysicsSteve Boggs, Chair

Devi Mathieu, Editor, Principal WriterMeg Coughlin, DesignCover and additional design assistance provided by Sarah Wittmer Susan Houghton, Director of Development and Communications

Department of Physics366 LeConte Hall #7300University of California, BerkeleyBerkeley, CA 94720-7300

Copyright 2015 by The Regents of the University of California

Non-Profit Org. U.S. PostagePA I D University ofCalifornia, Berkeley

University of California, BerkeleyDepartment of Physics366 LeConte Hall, #7300Berkeley, CA 94720-7300 ADDRESS SERVICE REQUESTED

For the latest information from the Berkeley Physics Department – news on current research, special events, lecture/demos, and student activities – visit our webpage.

PH YS I C S . B E R K E LE Y. E D U

Berkeley Physics graduate student poster session.

fall2015physicscover new outln.pdf 1 11/4/15 3:07 pm · 2020-01-01 · of prokaryotes – bacteria...

Documents