nyss-aapt meeting suny - brockport october 1, 2005 [email protected] manly/ much ado about...
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NYSS-AAPT meeting SUNY - Brockport
October 1, 2005
[email protected]://www.pas.rochester.edu/~manly/
Much ado about nothing:Much ado about nothing: the 30 minute the 30 minute guide to the universeguide to the universe
The intimate relationship between the very big and the
very small
Cosmology …
Inquiring minds want to know ...Inquiring minds want to know ...
Yo! What holds it together?Yo! What holds it together?
Fermi National Accelerator Fermi National Accelerator Laboratory (near Chicago)Laboratory (near Chicago)
What forces exist in nature?
What is a force?
How do forces change with energy or temperature?
How has the universe evolved?
How do they interact?
Force Source Range StrengthGravitation mass infinite 10-39
Electromagnetism Electriccharge
infinite 10-2
Strong nuclear Colorcharge
10-15 m 1
Weak nuclear Weakcharge
10-18 m 10-5
Mini-Ph.D. – Quantum Mechanics 101 Mini-Ph.D. – Quantum Mechanics 101
Lesson 1:Lesson 1:
Size actually Size actually doesdoes matter. matter.
Problem!
Heisenberg uncertainty
principle
Cannot have perfect
knowledge of both the position
and velocity
Heisenberg
Dear Steve,
Party
relatively hard!
-Al
The fundamental nature of forces: virtual particlesThe fundamental nature of forces: virtual particles
Et h Heisenberg E = mc2 Einstein
e-
ee++ee--
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ee++ee--
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ee++ee--
qqqq
ee++ee--
qqqq ee++ee--
qqqqee++ee--
qqqq
ee++ee--qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq
ee++ee--
qqqq qqqq
qqqq
ee++ee--
qqqq
ee++ee--
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ee++ee--
Much ado about NOTHING:Much ado about NOTHING:
Nothing is somethingNothing is something
Nothing has energy Nothing has energy
Nothing interacts with somethingNothing interacts with something
-R. Kolb
qqqq
qqqq
qqq
qqq
qqq
qqq
The essence of inertial mass at the quantum levelThe essence of inertial mass at the quantum level(quantum field theory)(quantum field theory)
On to the very big …
1 Mpc= 1 Megaparsec = 3x1022 m
1 light year = 9x1015 m
Light travels from NYC to San Francisco in 1/100 second …. and it travels 1 Mpc in 3 million years
Telescopes are Telescopes are time machinestime machines
Edwin Hubble (1889-1953) discovers a surprise in 1929
Galaxies that are further away appear redder
Apparent Doppler shift-From webphysics.davidson.edu
Type Ia SNe from Riess, Press and Kirshner (1996)
Welcome to the “expanding universe”!!
extrapolate back in time find the age of the universe 13 billion
years.
Light travels from NYC to San Francisco in 1/100 second …. and it travels 1 Mpc in 3 million years
Cosmic Microwave Background
Penzias and Wilson - 1964
Uniform and isotropic
– in as far as they could measure
Modern accelerators study processes at energies that existed VERY early in the universe
Another form of time travel !
What were forces like at those temperatures?
What types of particles existed?
How can the universe be so isotropic?How can the universe be so isotropic?
How did the structure (galaxies, clusters of galaxies) arise??How did the structure (galaxies, clusters of galaxies) arise??
Do we know about all of the fundamental particles that exist? Do we know about all of the fundamental particles that exist?
Why 3 families?Why 3 families?
Why is the mass spectrum of fundamental particles as it is?Why is the mass spectrum of fundamental particles as it is?
Why is the universe matter instead of antimatter?Why is the universe matter instead of antimatter?
Many, many missing pieces …Many, many missing pieces …
Recent progress! But new puzzles…-R. Kolb
Very exciting development in last decade
Observed fluctuations in the CMB temp
WMap data on the temperature fluctuations in the CMB
why structure matters
time12 billio
n years
17 billio
n years
100 billio
n years
1000 billio
n years
Millio
n- b
illion
years
Today
Sun burns out
Hell freezes over
Buffalo wins the Superbowl
End of universe
One possible future of the universeOne possible future of the universe
-R. Kolb
“Power spectrum” (size) of temperature fluctuations sensitive to different matter/energy components of the
universe
The elusive neutrinoThe elusive neutrino
ee + target + target e e-- + X + X
+ target + target -- + X + X
+ target + target -- + X + XFlavor eigenstates – relevant for Flavor eigenstates – relevant for weak interaction with other particlesweak interaction with other particles
Mass eigenstates Mass eigenstates (3 or more)(3 or more)
33
22
11massmass
44
The elusive neutrinoThe elusive neutrinoQuantum mechanical mixing of states:Quantum mechanical mixing of states:
||> = > = ΣΣiiUU**ii||ii>>
Weak flavor eigenstateWeak flavor eigenstate Mass eigenstateMass eigenstate
Unitary leptonic mixing matrixUnitary leptonic mixing matrix
Analogous to CKM matrix for quarksAnalogous to CKM matrix for quarks
Neutrino with momentum p evolves with time:Neutrino with momentum p evolves with time:
||(t)> = (t)> = ΣΣiiUU**ii||ii>e>e-iE-iE
ii(p)t/h(p)t/h
Neutrino of definite flavor is a superposition of several mass eigenstates Neutrino of definite flavor is a superposition of several mass eigenstates whose different masses cause them to propagate differently changing whose different masses cause them to propagate differently changing the mixture of the mass eigenstates, i.e. neutrino oscillations in vacuumthe mixture of the mass eigenstates, i.e. neutrino oscillations in vacuum
Solar neutrino puzzleSolar neutrino puzzleSolar neutrinos (only Solar neutrinos (only ee produced in core of sun) produced in core of sun)
Homestake Mine, Davis et al.Homestake Mine, Davis et al.
100,000 Gal tetrachloroethylene100,000 Gal tetrachloroethylene
3737Cl Cl 3737ArAr
ee(Homestake)/(Homestake)/ee(theory) ~ 0.34+-0.06(theory) ~ 0.34+-0.06
Homestake only sensitive to high E tail Homestake only sensitive to high E tail of of ee flux flux
Fisher, Kayser, McFarland, Ann. Rev. Nucl. Part. Sci. 49, (1999) 481.
Neutrinos physics in the last decadeNeutrinos physics in the last decadeSudbury Neutrino Observatory (SNO) Sudbury Neutrino Observatory (SNO)
1000 metric tons of D1000 metric tons of D22O in 12 m acrylic vessel O in 12 m acrylic vessel
esun
esun
esun
d
e
d
15.0
SNO: SNO: ee++=5.44+-0.99x10=5.44+-0.99x1066 cm cm-2-2ss-1-1
Bahcall: Bahcall: totaltotal ~ 5.05x10 ~ 5.05x1066 cm cm-2-2ss-1-1
SNO: SNO: ee/(/(totaltotal ) ~ 0.34 ) ~ 0.34
Neutrinos oscillate and have mass Neutrinos oscillate and have mass … solar puzzle solved!… solar puzzle solved!
Neutrinos physics in the last decadeNeutrinos physics in the last decade
SuperKamiodande SuperKamiodande
50,000 tons of pure H50,000 tons of pure H22OO
Atmospheric neutrinosAtmospheric neutrinosCosmic rays interact in atmosphere and produce e and neutrinos
Evidence for a sterile neutrino? Evidence for a sterile neutrino? MiniBooNE results in late summer or MiniBooNE results in late summer or
early fall …early fall …
The The future future
Long baselineLong baseline
Two detectors – one near, one farTwo detectors – one near, one far
High statistics – challenge for accelerator and detectorHigh statistics – challenge for accelerator and detector
On and off axisOn and off axis
Need to minimize systematic errorsNeed to minimize systematic errors
Thanks to:
Priscilla Cushman, CDMS, G-2, Univ. of Minnesota
Rocky Kolb, Fermilab and University of Chicago
Stanford Linear Accelerator Center
CERN, European Center for Particle Physics
Fermi National Accelerator Laboratory
Brookhaven National Laboratory
Davidson University webphysics project
WMAP project
Hubble Space Telescope project
Ned Wright, UCLA
MSSL astrophysics group
Newton, Einstein, Heisenberg, Plank, etc.
And whoever else I forgot to mention …
We live in exciting times!