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A newspaper developed as part of a writing class taught at the University of Massachusetts Amherst


<p>UMass</p> <p>D EPAR TMENT</p> <p>OF</p> <p>P HYSICS , U NIVERSITY</p> <p>OF</p> <p>M ASSACHUSETTS</p> <p>PHYSICS</p> <p>December 19, 2008</p> <p>ATLAS: LORD OF THE RINGSam Bingham and Matthew Mirigian, Amherst Some people are concerned that new experiments at the worlds largest particle physics laboratory could have some disastrous consequences. Perhaps it is due to the talk of high energy collisions possibly resulting in black holes. The Large Hadron Collider (LHC) will be capable of smashing protons at the highest energies seen in a laboratory setting. The colliders major ring, where the protons will zoom around at 99.999999 percent of the speed of light, is a circular track 17 miles in circumference and is located underground straddling the Franco-Swiss border near Geneva. [ . 9]</p> <p>A titan under constructionDARK ENERGY AND MATTER</p> <p>Where Did (Just About) Everything Go?Lorenzo Sorbo, our local cosmologistSebastian Fischetti and Rob Pierce, Amherst A couple walking down a street late at night notice a man, obviously drunk, searching for something under a streetlight. When asked about his behavior, the man replies, I lost my keys. Where? the couple ask. In the park. Then why are you looking for them here? Because here I can see.</p> <p>This story describes the manner of research of a cosmologist like Lorenzo Sorbo, a Professor of Physics at UMass Amherst. Because many ideas in cosmology, like dark energy, are still very obscure, sometimes cosmologists can only research within the known realm of physics before making progress on more mysterious topics. [ . 6]</p> <p>LIGO AND BOREXINO</p> <p>Making Waves at UMassLaura Cadonati brings a revolutionary perspective on the cosmos to AmherstPaul Hughes &amp; Daniel Rogers, Amherst Albert Einstein is a household name. Most people know that E = mc2 , and that funny things happen to space and time at speeds near that of light. A less commonly known prediction of relativity, however, is the existence of gravitational waves, which have yet to be directly observed. Since the cornerstone of scientic progress is the verication of such predictions, this is a problem for Einstein and his theory. Fortunately for him, there is LIGO (the Laser Interferometer Gravitational-Wave Observatory), which hopes to Laura Cadonati nally detect gravitational waves. The project is a collaborative eort of about 500 scientists from across the country. One of them, Dr. Laura Cadonati, has helped to start a gravitational waves research group in the UMass Amherst Physics department. [ . 12]</p> <p>Boone &amp; Rines: Fifth force 2 Kerrigan: Future physics 4 ODonnell: The electron: a dipole? 5 Fischetti &amp; Pierce: Dark cosmology 6 Parker: Universe expanding 8 Bingham &amp; Mirigian: God particle 9 Deegan &amp; MacLellan: Atom smasher 10 Hughes &amp; Rogers: Gravity waves 12 Fratus &amp; Lund: Neutrino oscillations 14 Drake: Complexity 16 Emma: Food nanotech 17 Cervo: Cell imaging 18 Mortsolf: Molecule ashlight 20 Kiriakopoulos: Single molecules 19 Herbert: New matter 22 Lally: Thin-lm buckling 24UMass University of Massachusetts</p> <p>PHYSICS</p> <p>A student will never do all that he is capable of doing if he is never required to do that which he cannot do. Herbert Spencer</p> <p>UMass PHYSICS</p> <p>December 19, 2008</p> <p>2 / 24</p> <p>THE FIFTH FORCE</p> <p>Rules of AttractionHow a simple experiment challenged centuries of physical theorySam Boone and Rich Rines, Amherst</p> <p>In Northeld, Massachusetts, 935 feet above sea level on Northeld Mountain, engineers in the 1970s created a massive lake (pictured). The mountain and area surrounding the lake serves as a public recreational area for the surrounding towns. At rst glance, the lake may not seem unusual (save for its articial cement edges), but with an extended stay, visitors would notice an overwhelming peculiarity: the height of the water in the lake is in dramatic constant uctuation. Deep underground and below the surface of the lake, water turbines are responsible for continuously draining and relling of the lake. When there is an excess of electricity in the area, the pumps use it to ll the reservoir with water from the Connecticut River. This water is then released from the lake through large generators in times of electrical demand. And what is most peculiar about this lake is not its intrinsically unusual nature, but</p> <p>a single physical experiment completed there in 1991. Physicists have long characterized interaction in terms of four fundamental forces. Gravity keeps us on the ground. Electromagnetism, being much stronger than gravity, keeps atomic structures rigid, so that we dont fall through that ground. The strong nuclear force, stronger still, holds those atoms themselves together. The weak nuclear force, though less obvious in everyday experience, is responsible for the nuclear activity that makes the sun burn. Without these forces the infrastructure of our universe would collapse leaving us with a completely chaotic and intangible universe that we cannot begin to imagine. Each of these forces are dened by their particular sources, or properties of matter which are attracted or repelled. Electromagnetism, for example, is a product of the electric charge. Gravity, by contrast, is solely a function</p> <p>of an objects mass. In this way, all objects (including ourselves) experience a small attraction toward one another, which is greater the closer together the objects are. This is the cause of Galileos infamous 17th-century claim: that all objects, without the eects of wind resistance, fall to the Earth with the same acceleration. This principle is known as weak equivalence, and has been tested with high precision many, many times. Years later, Sir Isaac Newton used this as the basis for his gravitational explanation of planetary orbits. But late in the 1970s, three centuries after the times of Galileo and Newton, physicists began questioning their fundamental assertions. Motivated by certain sub-atomic phenomena that could not be explained by any existing physical law, they were beginning to suspect yet another, fth fundamental force, with its own unique source. As this source would presumably be dierent for</p> <p>c - Created using paperTEX</p> <p>UMass PHYSICS</p> <p>December 19, 2008</p> <p>3 / 24</p> <p>dierent kinds of materials, they would fall to Earth with slightly dierent accelerations. This would mean an end for weak equivalence. And being much weaker and less prevalent than even gravity, this force could have gone undetected through any previous experiment. It was the existence of this new force that Paul A. Nakroshis, as part of his PHD thesis, for the University of Massachusetts under the direction of Professor Bob Krotkov, began to experimentally search for on the side of Northeld Mountain, in the Metropolitan District Commission (MDC) Building. Nakroshis saw that the Northeld Reservoir provided a perfect testing sight for a possible fth force. All objects are, to some small extent, attracted to each other via gravity. A fth force would, presumably, provide this same universal interaction between objects. However, unlike gravity, dierent objects of the same mass could be either attracted or repelled from one another. The strength of this attraction or repulsion would also vary between dierent materials. Nakroshis used this as the basis for his experiment. The changing volume of water in the reservoir provided a constantly changing source of attraction for nearby objects. When the reservoir is full, objects suspended nearby should have a measurable, however miniscule, attraction toward the</p> <p>great water mass. This attraction diminishes as the water is emptied from the lake. Under just the eects of gravity, this attraction would be identical for all objects of the same mass. However, with the addition of a fth force that is dependent on some other property of the material, the attraction of dierent kinds of materials toward the lake would be slightly dierent. This dierence is readily tested: by hanging two dierent materials of equal mass in balance once the lake has been drained and then allowing the lake to rell, the balance would tip so that the object most attracted to the water could get closer. Nakroshis used a variant of this procedure in his experiment. He assumed, as did most fth-force research at the time, that the source of the force was an atomic property known as baryon number. This is a property which varies slightly between dierent kinds of atoms, and therefore between dierent kinds of materials. The two materials he compared were copper and polyethylene, which are known to have very dierent baryon numbers. He balanced these materials on a metal rod which was allowed to oscillate, much like a horizontal version of a clocks pendulum, known as a torsion pendulum. Just as the speed at which a clocks pendulum swings changes when the pendulum is made heavier or lighter,</p> <p>the attraction between each material and the changing amount of water would theoretically alter how fast the torsion pendulum oscillates. Nakroshis experiment was one of many in search for a violation of the weak equivalence principle at the time. The physics community at the time was captivated by the possibility of a new, undiscovered fundamental force. Nakroshis test diered, however, from the majority of fth force experiments, in his utilization of such a large amount of uctuating material. The unique Northeld Reservoir provided this huge uctuating body. Like the other fth-force experiments at the time, Nakroshis results were inconclusive. As these results came in, physicists more and more began to ee from the idea of the existence of a fth force. A little more than a decade after its proposal, the fth-force proposal was beginning to ounder. Eventually, as no positive, reproducible experimental results were being reported, the force was largely considered dead. In this way, weak equivalence and the ideas of Newton and Galileo were once again considered accurate. It was not until the rise and fall of the fth force, three centuries and thousands of experiments after their conception, that these laws had been tested and conrmed with such high meticulousness.</p> <p>Left to Right: Nakroshis, Sakai and Krotkov with the experimental apparatus.</p> <p>c - Created using paperTEX</p> <p>UMass PHYSICS</p> <p>December 19, 2008</p> <p>4 / 24</p> <p>CONTEMPORARY THEORY</p> <p>A Ripening RealityExploring two controversial new physical theoriesChris Kerrigan, Amherst A chapter in contemporary physical theory may be drawing to a close. Physicists have long made the comparison of reality to an onion, having layers of truth to be explored and later discarded when further research reveals a deeper or more fundamental existence. Right now, many of the worlds top physicists have thoroughly explored current theories suciently enough to decide that its time to peel back a new layer. The current description of reality agreed upon by most physicists is called the Standard Model. This theory depends on an idea everyone has heard, that of the fundamental building blocks of existence. The Standard Model describes a few fundamental interactions, or forces, that occur in nature, and the elementary particles that take part in these interactions. When all is said and done, this theory gives us 26 constants (unchanging numbers that describe various quantities) which describe reality; the mass of the electron is one of these, for example. Physicists are now ready to take the theory a step further and discover what created these particles and what determines these constants. I was recently able to sit down with Professor of Physics at the University of Massachussetts at Amherst John Donoghue, who quite literally wrote the book on the Standard Model (it is entitled The Dynamics of the Standard Model), and discuss the future of physics. His recent claim to fame is a theory of the multiverse. The theory is as surprising as the name suggests. The idea is that the 26 constants brought forth by the Standard Model could have been assigned at random by nature. Not only that, but in dierent domains of our universe, which is perhaps larger than we expect, there exist places where the 26 constants were assigned dierently. This means that our entire universe consists of separated, smaller universes that each have their own set of constants and therefore behave very dierently. Perhaps in one universe the mass of the electron turned out to be very great and so gravity made it collapse very quickly. Perhaps in another the constants worked in such a way that there was only one type of particle, and so nothing ever happened. The implications of this theory are that we live in one of the few possible universes that could exist as something other than a clump of particles, and that this universe only came about through the trial and error process of nature playing with 26 constants. It is a lot to stomach to hear this about the universe we have come to know and love, but it may also be a step closer to the truth. A dierent theory suggested by Donoghue is even more abstract, but pushes further toward the center of the onion. It involves the concept of emergence, the way patterns arise out</p> <p>of simple interactions, and has been called the opposite of the popular String Theory. Though easy to dene, the idea of emergence is hard to properly conceptualize. The classic example is to look at the notion of a wave. We can have waves in water, sound waves in the air, electromagnetic waves, etc., yet there is no such thing as a water-wave particle, or a sound particle, or an electromagnetic particle. The idea of the wave is nothing more than a convenient way to describe what happens on a larger scale when small particles interact with each other. Regular water molecules rub against each other in a way that creates wave motion. Regular particles in the air bounce o of one another to create alternating regions of high and low pressure that we call a sound wave. Emergence, then, is the concept that embodies this. It is the means by which our concepts to describe macroscopic phenomena come about. So what does emergence have to do with reality as we know it? Donoghue is beginning to lean toward the answer everything. The idea is that many of the things we describe are emergent properties of more fundamental interactions (for example, waves happen even though, in a sense, there are no real waves), so why not take it a step further (as is often the physicists wont)? Knowing that phenomena occur based on the interactions between the particles described by the Standard Model, we may riskily say that the Standard Model itself is nothing more than an emergent phenomenon of something even more fundamental. That is, elementary particles may seem to exist, but are in fact just a convenient way to describe some deeper interactions. When asked about the nature of these interactions, Donoghue replied, We cant go there yet. Indeed the idea of the Standard Model as an emergent phenomenon rather than a found...</p>