University of Pennsylvania

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The cosmic connection
From WMAP web site
Licia Verde
University of Pennsylvania
www.physics.upenn.edu/lverde
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History
You are here
Danielsson tHooft talks
Cosmic archeology!
Expanding and cooling
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Look inside Particle accelerators
(Wagner talk)
Exhibition in Pillared Hall
Or.. theory
Russian doll
looking at the sky
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Russian doll
The cosmic connection the big picture
The cosmic connection the details an example.
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Matter (and energy) curves space-time
1915
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Vacuum energy
L
(also known as dark energy or cosmological
constant)
1917
vacuum
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Humm.. Looks like the Universe is expanding
My biggest blunder..
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Some recent observations
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A picture of the baby Universe
380,000 years after the big bang
Cobe 1994
WMAP Today
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From W. Hu web site
Fig. From WMAP web site
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Tiny ripples in density ? seeeds of galaxies
Hot and cold spots ?
Detailed statistical properties of these ripples
tell us a lot about the Universe
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Hows that?
The Universe back then was made of a very hot and
dense gas, so it was emitting radiation
This is the radiation we see when we look at the
CMB
Uniform , but with tiny (contrast x 100000)
density (and temperature) ripples
Ripples in a gas? SOUND WAVES!
We are seeing sound!
Truly a cosmic symphony
These tiny fluctuations, quantitatively, give
rise galaxies
We try to listen to the sound and figure out how
the instrument is made
Fundamental scale? Fundamental mode and overtones
like blowing on a pipe.
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Magnitude of temperature variations
Size of spots smoothing

From WMAP
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Fundamental mode
(Geometry)
overtones
(content, history)
Primordial ripples
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From WMAP web site
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There is more mass than you can see!!!
Abell 2218, direction of Draco (Hubble)
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Galaxy surveys
2dF galaxy redshift survey
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How?
Tools statistics.
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Additional indications Supernovae
Standard candles
Expansion history!
Do like Hubble, just .. better
Function of geometry and Content of Universe
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Figure from a scientific journal
Science for real
Vacuum Energy density or
Supernovae
CMB
Dark energy
Galaxy survey
Line of flatness
Universe is FLAT
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The Universe is Flat
From WMAP web site
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Looks curved
Looks Flat !!???
.
.
Remember Inflation?
What made the Universe so flat?
What made the Universe so big?
What made the universe so uniform?
(Danielsson talk)
What seeded the galaxies?
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We (and all of chemistry) are a small minority in
the Universe.
Components of
Wheres the anti-matter?
We do not know what 96 of the Universe is !
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Recap
We have a consistent and coherent picture of the
Universe. Things have clicked into place
Different observations agree quantitatively.
They all point in the same direction the
standard model for cosmology
The standard model for particle physics ?? The
standard model for cosmology
Some puzzles remain
Baryons wheres the anti matter?
GUT?
Dark matter what is it?
The standard model offers candidates If SUSY is
discovered at colliders we could measure DM
abundance and compare with cosmological results!
Dark energy not a clue.
Standard model predictions are 60 to 120 orders
of magnitude larger than observations
Inflation
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the dark side of the Universe
We have indications that
More than 90 of the mass in the Universe is
DARK
About 85 of mass in the Universe is made of
matter unknown to Earth
About 80 of whats in the Universe is not even
matter!!!! We call it DARK ENERGY
Wouldnt it be nice to start figuring some of
this out?
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The cosmic connection on all scales example
neutrinos
They ARE non-baryonic dark matter
Only not all of it!
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There are neutrinos everywhere!!!!
SuperNovae
Relict from the big bang
3
per m
Cosmic rays
reactors
accelerators
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100s million every second
?
A neutrino needs to cross 200 Earths before
having a chance to interact
So do not worry.
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They are incredibly Petite
?
The standard model requires massless neutrinos
But do they have mass?
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How does the sun Shines?
Full details of how this happens called Standard
Solar Model
How could we prove this?
Detect and count solar neutrinos!
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To cut a long story short
Solar Neutrino Experiments
First experiment by Davis et al in 1960s
Radiochemical Method (Chlorine)
Found 1/3 of Standard Solar Model (SSM) rate
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The explanation?
So they must have mass!
At odd with the standard model prediction
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2002
Got Nobel Prize
Look at the ECFA exibition in Pillared hall for
more neutrino stuff
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What you should take away
Cosmology and particle physics now are asking
the same fundamental questions.
They approach them in complementary ways
THE END
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Further readings, figure sources etc.
WMAP web site (basic) http//map.gsfc.nasa.gov/i
ndex.html
WMAP web site (advanced) http//cmbdata.gsfc.nasa
.gov/product/map/
2dFGRS web page http//www.mso.anu.edu.au/2dFGRS/
Scientific American article on CMB by Hu and
White http//background.uchicago.edu/whu/Papers/H
uWhi04.pdf (in Scientific American February
2004)
Wayne Hu web page http//background.uchicago.edu/
whu/
Scientific American article on Supernovae Scienti
fic American vol. 290, February 2004