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That other pesky 95%Dark Energy and Dark Matter
Prof. Lawrence WienckeDepartment of Physics EngineeringColorado School of MinesNov 9 2011
The Dark SideThe Dark Side
95% of theUniverse Is Dark!
Energy budget of Universe
• Stars and galaxies are only ~0.5%• Neutrinos are <1%• Rest of ordinary matter (electrons and protons) are ~5%• Dark Matter ~25%• Dark Energy ~70%• Anti-Matter 0%
THE HIGGS!?#
No Dark MatterNo Dark Energy
M81Spitzer Space Telescope
105
100
50
Expected if the mass of the galaxy = the mass we can see
Observed
Some sort of invisible Mass must extend out ~10 times further than the stars!
Ro
tati
on
sp
eed
Distance from the center
Vera Rubin 1980s
Full Court Press!!Produce at an acceleratorDetect them in our haloDetect annihilation products
Dark Matter annihilating in our halo should produce positrons,
neutrinos and gamma rays
Evidence for Dark Matter from Lensing
Einstein: Gravity bends light
Light travels along straight lines unless it passes a massive object.
Light coming from behind a massive object such as a star, a galaxy, a cluster of galaxies or a clump of dark matter will be bent the same way a glass lens works.
The more massive the object, the more gravity it has and the more the light is bent
giant arcs are galaxies behind the cluster, gravitationally lensed
Zoom in on a galaxy cluster – Gravity from the invisible matter is bending light and we can see the distorted images that result
Michael S Turner
Discovery of Cosmic Microwave Background, 1964
Michael S Turner
The Universe circa 380,000 yrsWMAP
±0.001% Fluctuations
fraction of a second later
Hot Primordial Soup
380,000 years later
Radiation Last Scattered
13.78 thousand-million years later
Today
DARK MATTERfrom the
Primordial Soup
DARK MATTERfrom the
Primordial Soup
Most of the matter is dark
and
it’s not even “normal” stuff!
Tip of the IcebergTip of the Iceberg
STRING THEORY - 11 dimensions and more …..
Go to 11???
19
What is Dark Energy ?What is Dark Energy ?
“ ‘Most embarrassing observation in physics’ – that’s the only quick thing I can say about dark energy that’s also true.”
Edward Witten
Discovery! – 1998
Hi z Supernova TeamSupernova Cosmology Project
Brian P. SchmidtSaul Perlmutter
Adam G. Riess
Nobel Prize in Physics 2011
Inquiring into Dark Energy
22
NSTA - Baltimore 2006
A dying star becomes a white dwarf.
1. Create a White Dwarf
Inquiring into Dark Energy
23
NSTA - Baltimore 2006
The white dwarf strips gas from its stellar companion….
2. Dump more mass onto it
Inquiring into Dark Energy
24
NSTA - Baltimore 2006
….and uses it to become a hydrogen bomb. Bang!
3. Until it explodes
Inquiring into Dark Energy
25
NSTA - Baltimore 2006
The explosion is as bright as an entire galaxy of stars….…..and can be seen in galaxies across the universe.
4. Observe it in a distant galaxy
The Sloan Digital Sky Survey (SDSS) is a telescope Fermilab helped build and operate.
It has a 2.4m mirror and no Dome
Located in New Mexico• First started collecting images in 2000•120 MegaPixel digital camera
SDSShas measured ~ 1 million galaxies and over 500 type 1a Supernova and also found that the expansion of the universe is accelerating
SDSS-II Supernova Survey
~500 Well studied SNe Ia, suitable for framing
Our Universe’s Expansion is Accelerating!
time
exp
ansi
on open
closed
accelerating
Now
“The most beautiful thing we can experience is the mysterious. It is the source of all true art and all science. Those to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, are as good as dead: their eyes are closed.”
Albert Einstein
95% of theUniverse Is Dark!
What can we learn about it?
Will!!
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