fran ç ois passebon & jack willis hst 2006 present …
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Fran ç ois PASSEBON & Jack WILLIS HST 2006 present …. I pump, therefore I am. If you compress a gas in a pump, it becomes hotter, and if you release the pressure of this gas, it cools. Color is related to temperature. An animal, or a human body, for example, emits - PowerPoint PPT PresentationTRANSCRIPT
François PASSEBON & Jack WILLIS
HST 2006
present …
If you compress a gas in a pump, it becomes hotter,and if you release the pressure of this gas, it cools
I pump,therefore I am
An animal, or a human body, for example, emitssome infrared radiation that can be detectedby an infrared camera
Color is related to temperature
Dicke and Gamov, two physicists, calculated independently in 1946 and 1948, that as the Universe has cooled, we should be able to detect microwave radiation throughout the sky …
I’m Gamov
I’m Dicke
Longwave-
-length
Lowtemperature
Max Planck, another physicist,had given the explanation of theshape of the radiation in 1900
The colder the body,the longer the wavelenght
… by Penzias and Wilson, two physicistsfrom the Bell labs, who got the Nobel prize in 1978
But, in 1964, the radiation predicted by Gamovwas finally detected, with this antenna …
antenna
PenziasWilson
In fact, the snow that one can see on an untuned TVis also due in part to that radiation emitted by theUniverse as it was just 380,000 years old !
We’ve a lot of
work today !
Original temperature of the radiation : 3000 KToday, it is only 3 KThe cooling says how far the light has travelled13,7 billion years : the age of the Universe
In 1992, the COBE satelite (Cosmic Background explorer)gave the first image of the radiation
COBE was launched on November 18, 1989
In 1992, the COBE satelite (Cosmic Background explorer)gave the first image of the radiation
Before correction of the Earthmovement around the Sun
The final image of the microwaveRadiation
Before correction of the microwaveradiation emitted by our own galaxy
In 2003, the WMAP satelite gave a better resolutionof the small fluctuations of temperature(WMAP = Wilkinson Microwave Anisotropy Probe)
WMAP was launched on June 30, 2001
Whereever it looked, WMAP measured the same data.So, the big-bang must have taken place at the same time everywhere
But we can also observe small fluctuations of temperature, that may have lead to the formation of the galaxies
Small fluctuations, compared to these at the surfaceof the Earth !
To know more about the blackbody spectrum :
Back to the begining
Where does the matter of the universe come from?
1 proton for every 1,000,000,000 photons
How did structures in the universe form?
Ripples + Dark Matter
Albert Einstein, 1905
E = mc2Mass is just condensed
energy
E → m
What was the origin of this early matter (and antimatter) in the Early Universe?
Early Universe
Size: a → 0
Age: t → 0
Temperature: T → very large
T ~ 1/a, t ~ 1/T2
Energies: E ~ T
Based on Einstein’s Relativity + Dirac’s Quantum Theory + Feynman’s
description in Quantum Field Theory
We conclude:
Every particle has an antiparticle
Because of asymmetry, almost all particles and
antiparticles were annihilated except for a small number of particles
Why do we not see this in our evidence?
Dirac predicted the existance of antimatter in 1928
He predicted antimatter would have the same mass but opposite internal properties of matter
1957: particles and antiparticles spinning in same direction behave differently
1964: CP violation shown in weak decays of K0 mesons indicating matter does not behave
exactly as antimatter.
Current evidence suggests:
Density Budget of the Early Universe
● Total Density ~ critical
Theory of inflation, measurement
of microwave background: ΩTot = ~ 1
● Baryon Density smallBig-Bang nucleosynthesis, CMB:
ΩBaryons ~ few %
The Density Budget of the Universe
● Total Density ~ critical
Theory of inflation, measurement of microwave background: ΩTot = ~ 1
● Baryon Density small
Big-Bang nucleosynthesis, CMB:
ΩBaryons ~ few %
● Total Matter Density much larger
Clusters of galaxies
Ωmatter ~ 25%
● Mainly cold dark matter
Enables structure formation
What caused the formation of the structures of the universe and what was
the origin of masses and forces?
Evidence indicates that as the universe cooled after the Big Bang….
These particles began to cluster….
And in these clusters developed patterns….
Such as quarks….
And atoms
How do these particles stay together to form structure?
FORCES
Standard Model: Gravity, Electromagnetic, Strong and Weak
Two Theories describe the forces:
Quantum Electrodynamics and
Quantum Chromodynamics.
Quantum Electrodynamics (QED):
Electric charge Atoms Molecules
Quantum Chromodynamics (QCD):
Colour charge Baryons Nucleus
At current resolution we see the universe as it was ~ 380,000 years
after the ‘Big Bang”
What will we see next?
Perhaps…..
B I G
B A N G