the universe and us
TRANSCRIPT
THE UNIVERSE AND US
Debjyoti BardhanResearch Scholar
Theoretical PhysicsTIFR
INSEF SCIENCE FAIR
28th September, 2013
City Lights in QuebecCourtesy: http://wallpaperhd.net
Starry NightsBy: Vincent Van Gogh, 1889
What’s theDifference?
UNDER THE STARS…
LIFE,THE UNIVERSE &
EVERYTHING
THE UNIVERSE
A UNIVERSE IS MADE
If you wish to make an apple pie from scratch,you must first invent
the Universe- Carl Sagan
Quick Word: EM Spectrum
THE BIG BANG
The Universe came from a space-time singularity
The fiery birth happened 13.7 billion years ago!
The Universe has been expanding since
Expansion causes cooling – the Universe has since cooled
And the Universe is still expanding – and accelerating!
What We See Today
BUT HOW DO WE KNOW?
We can Hear
The Universe softly speaking to us
Literally!Penzias and Wilson with their horn antenna
The Cosmic Microwave Background
RELICS OF THE BIG BANG We are listening in with bigger instruments – in space!
Cosmic Microwave Background Explorer - CoBEWilkinson Microwave Anisotropy Probe - WMAP
We are listening in with bigger and bigger instruments – in space!
PLANCK
The UNSEEN STUFF
Dark MatterFritz Zwicky
VisibleThe Bullet Cluster XRay
The EXPANDING UNIVERSE
Every galaxy is moving away from each other
The Universe is EXPANDINGEdwin Hubble
The ACCELERATING UNIVERSE
Recent observations show that the Universe is expanding at a faster and faster rate
Some mysterious force is pushing all galaxies away from each other
Scientists call it DARK ENERGY
We have NO CLUE as to what it is!
The largest constituent of the Universe!
MAKE-UP OF THE UNIVERSE
DataFrom
PLANCK
Most of the Universe is a complete
MYSTERY
LIFE,THE UNIVERSE &
EVERYTHING
L I F E
Quick Quiz:
Does Nuclear FusionHeat up or Cool Down
A Star?
Ans: It Cools Down the star
A Fine Balance
GravitationRadiationPressure
What happens when the nuclear fuel runs out?
She said "Look at how pretty the stars shine!" He said, "Yes, and right now I am the only manin the world who knows why they shine."
She merely laughed at him. She was not impressed with being out with the only man who, at that moment, knew why stars shine.
Eddington was out with his girlfriend on a moonless night and held hands under the open sky
Eddington remained a lifelong bachelor
Twinkle Twinkle…
LIFE BEGINS IN STARS
The Universe must provide all the elements needed for life
Stars are the kitchens for these elements!
All elements starting from Helium to Uranium are produced in stars
Nuclear fusion produces heavier and heavier elements
MAKING OF ELEMENTS
Easy, right?
• Take a proton and make the next element - Helium
Not so fast!
Actually, Not So Slow!!
Fast and Furious!
There is a stronger force
Strong Force Much stronger than the Electromagnetic Force
Acts on extremely small length scales
The Bigger They Are, The More They Make Heavier stars make more elements
Heavier elements need more temperature and pressure
The Sun will make till only Carbon/Oxygen
Only the heaviest stars make elements like Iron
No element heavier than Iron can be made in stars!
A Diagram of Stars
In another 5 bn years, the Sun will become a Red Giant
It will barely make Carbon & Oxygen
Lives of Stars
Insides of Heavy Stars
Different Stages of Stars
Supernovae release these elements into space!
Every atom in your body came from The Cores of Stars
Stars died so that you could live
-Lawrence Krauss, physicist
The Cosmos is also within us.We are all made of Starstuff
-Carl Sagan, astronomer
LIFE ON EARTH Life somehow arose on Earth – we do not know how!
Self-replicating machines arose
Information containing replicating structures – RNA & DNA
RNA or DNA are stored inside genes within cells
Evolution is all about the survival/extinction of genes
Basics of EvolutionAn organism is a gene-carrying machine
The survival and reproduction of the individual means that a set of genes are replicated and passed on
Survival is all that a gene cares about!
The genes which populate the gene pool the most are the ones most likely to survive the longest
SURVIVAL of the FITTEST
What are Genes?Genes are like hard spherical balls of a particular colour
They are copied from one generation to another almost exactly
A gene pool is a pool of all such genes!
During sexual reproduction, half of the set comes from the mother and the other half from the father
A mutation, while rare, is INTERESTING
Ingredients for DarwinismMutations can affect the reproductive capability of the organism
If the mutations help the individual, they are selected!
When Nature selects, it is Natural Selection
Two Steps to Speciation1. Random Mutation 2. Natural Selection
Needed: A Huge Amount of Time
The Tree of LifeEvery species is connected to one another
Phylogenetic Tree
We AreAll
Connected
Bat and Man
Certain body parts change, according to the actions they perform
The basic structure remains the same
Indelible Stamp of Lowly Origins
Recurrent Laryngeal Nerve
~15 feet detour!
Darwin’s Finches
Seeing this gradation and diversity of structure in one small, intimately related group of birds, one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends. In a like manner it might be fancied that a bird originally a buzzard, had been induced here to undertake the office of the carrion-feeding Polybori of the American continent.
-- Charles Darwin, Voyage of the Beagle
Rabbits in the PrecambrianOne observation to prove evolution wrong?
“Rabbit Fossils in the Precambrian” – J.B.S. Haldane
Evolution Works!One anachronistic fossil would ‘completely blow evolution out of the water’
Today the theory of evolution is about as much open to doubt as the theory that the Earth goes round the Sun
Richard Dawkins
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.
Charles Darwin
LIFE,THE UNIVERSE &
EVERYTHING
And EVERYTHING
Your inspiration and imagination are soaring today. You may want to try an artistic project of some kind. You could be pleasantly surprised at the results. Your intuition is also high, and your understanding of those around you is greatly increased. Don't be afraid to act from instinct. This is one of those days when it should win out over rationality and logic!Some misunderstandings could cause confusion in the home. Your intuition and insight should defuse the situation, especially since you're more diplomatic than usual. You could also have an artistic inspiration, perhaps a new project that could be very important to you. It could be important to your career or it could open up new opportunities for you.
Emotions could run high among those close to you. It might seem like everyone is in a bad mood! In your own relations with them, your friendly nature and social skills will calm them down and keep them on an even keel, at least when you're around! Social events may keep you busy. You could make some valuable contacts.
A welcome letter, phone call, or perhaps visit could come from a lover or close friend bringing interesting news. Your creative energies are bubbling over so you might want to try writing, music, drawing, or painting. You might send some letters, place a lot of phone calls, or make a lot of short trips in your neighborhood, maybe to libraries or bookstores.
SPOT A PATTERN
We aim to seek patterns where there are None!
THE DEMON-HAUNTED WORLD
The human mind can find patterns, just as an evolutionary baggage
It is an attempt to explain things we do not understand!
Often it is difficult to differentiate science and pseudo-science
Question everything.
Be a SCEPTIC!
Always ask the following questions
How reliable is the source of the claim?
Does this fit with the way the world works?
Is the claimant playing by the rules of science?
Does the new theory account for as many phenomena as the old theory?
Are personal beliefs driving the claim?
PSEUDO-SCIENCE DETECTION
AstrologyReliability of sources:
Fitness with world:
Rules of Science:
Accounting for old phenomenon:
Personal beliefs:
No scientist supports it!
Assumes the Earth to be at the center
Explains nothingMakes assertions
No Research goes on
No verifiable evidence
Not falsifiable
Depends strongly on beliefs
VERDICT: Astrology is Rubbish
TAKE HOME MESSAGE
Science explains a lot!
If it doesn’t, the explanationwill come from science
Be a Scientist!!
LIFE,THE UNIVERSE &
EVERYTHING
And A LITTLE MORE
THE PALE BLUE DOTLook again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every "superstar," every "supreme leader," every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.
Carl Sagan
The Voyager Image
ANOTHER PALE BLUE DOT
Solar Eclipse from Saturn,Cassini
TEN BOOKS
Thank You