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New Views on the Universe. V èmes Rencontres du Vietnam August 2004. Angela V. Olinto Astronomy & Astrophysics Kavli Institute Cosmol. Phys. Enrico Fermi Institute University of Chicago. Much to celebrate!. Success of the Big Bang theory Flat Universe (Inflationary prediction)
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New Views on the Universe Vèmes Rencontres du Vietnam August 2004 Angela V. Olinto Astronomy & Astrophysics Kavli Institute Cosmol. Phys. Enrico Fermi Institute University of Chicago
Much to celebrate! • Success of the Big Bang theory • Flat Universe (Inflationary prediction) • Discovery of Universe’s Acceleration • Discovery of Neutrino mixing mass • Gamma-ray Bursts Cosmolog.+ Counterparts • Black Holes in every galaxy! • TeV Gamma-ray Sources Many questions remain... Vèmes Rencontres du Vietnam 2004
The Big Bang We live in a Homogeneous & Isotropic Universe described by (a Robertson-Walker metric & Friedmann’s equation derived from) Einstein’s General Relativity. It began 13.7 billion years ago, and is composed of... Celebrate Einstein Centennial!
Evidence for Isotropy: The Microwave Sky! T = 2.725 0.002 K
b Big Bang Nucleosynthesis Theory vs. Observations: Remarkable agreement over 10 orders of magnitude in abundance variation Concordance region: b h2 = 0.02 For h=0.7, b = 0.04. Deuterium: strongest constraint 4He
add Inflation and we can explain...
Brief History of the Universe Inflation exponential expansion
Homogeneity & Isotropy Horizon of observer B at time of decoupling A B Big Bang t=0 Us, today Photon Decoupling (Last Scattering Surface) t=300,000 yr CMB naturally appears isotropic
V() Quantum Fluctuations of the `Inflaton’ Field ==> Density Perturbations field V() space field
Today Scale grow 3000 Mpc 1 Mpc stretch inside outside inside Time Before inflation Radiation Domination Matter Domination During inflation Dark Energy Domination
High-Resolution Simulations of Cold Dark Matter (CDM) Halos
CMB Anisotropies tU =380,000 yr, T 10-5 T
WMAP Precision Cosmology
Inflation predicts: FLAT Universe
Dark Energy? total = +DM +b = 0.73, DM = 0.23, b = 0.04
SnIa WMAP (h fix) LSS 2dF
Radiation - Matter - Vacuum (Dark Energy?) (a) a-4 a-3 const a Early Universe today
Expect dq/dz Riess et al. ApJLett 04, HST 16 SNIa
Towards = 1 closed expands forever recollapses open
Much to celebrate! • Success of the Big Bang theory • Flat Universe (Inflationary prediction) • Discovery of Universe’s Acceleration • Discovery of Neutrino mixing mass • Gamma-ray Bursts Cosmolog.+ Counterparts • Black Holes in every galaxy! • TeV Gamma-ray Sources
Official detections by H.E.S.S. Crab Nebula (2003, 3 Tel.) - 54 sigma PKS 2155 (2003, 2 Tel.) - 45 sigma Mrk 421 (2004, 4 Tel.) - 71 sigma PSR B1259 (2004, 4 Tel.) - 8 sigma RX J1713 (2003, 2 Tel.) - 20 sigma Sagittarius A* (2003. 2 Tel.) - 11 sigma Linton, WatsonFest, Leeds July 2004
HESS Galactic Center! Linton, WatsonFest, Leeds July 2004
What is the Dark Matter? F. Zwicky Coma cluster
HESS Galactic Center neutralino m > 10 TeV ??? Linton, WatsonFest, Leeds July 2004
Many questions remain • What is the Dark Matter? • What is the Dark Energy? • What is the origin & max energy of cosmic rays? • Astro-Physics at high energy, curvature, and/or density? • What are the neutrino masses and underlying theory? • Why is there something rather than nothing? • Is there A Fundamental Theory? Quantum Gravity, Large Extra-Dimensions, Strings, M-theory,...? • How did the Universe Begin?
Cosmological Constant Natural scale for : Contrast with: + coincidence… ~M
Many questions remain • What is the Dark Matter? • What is the Dark Energy? • What is the origin & max energy of cosmic rays? • Astro-Physics at high energy, curvature, and/or density? • What are the neutrino masses and underlying theory? • Why is there something rather than nothing? • Is there A Fundamental Theory? Quantum Gravity, Large Extra-Dimensions, Strings, M-theory,...? • How did the Universe Begin?
Cosmic Rays • 1912 discovered by Victor Hess • (after Wilson & others) • Energy range: • ~ 109 eV to > 1020 eV • 1938Pierre Auger discovered • Extensive Air Showers (EAS) ORIGIN? Unknown! soon to be a Century Old Puzzle! at all energies…
HESS 2 smoking guns CR acceleration! Galactic Centre - 11 RX J1713 - 20 Linton, WatsonFest, Leeds July 2004
CRs at the Highest Energies Great Opportunity for Discovery can traverse longer distances than photons can point back to the source should have spectral features
cosmic rays / / / / / / / / / / / n
UHE proton trajectories in Extra Galactic B at the Highest Energies (1020 eV)) - should point to sources (unless Magnetic Fields are stronger &/or Z is larger) Isola, Lemoine, Sigl ‘02 lower bound 2 1019 eV to 3 1020eV, E-2.4 injection, BMpc ~0.3 G, Kolmog
6 doublets 1 triplet above 4 x 1019 eV < 2.5 deg AGASA above 1019 eV Log E>19.4 Log E>19.6
HiRes HiRes-I Monocular Data, E > 1019.5 eV No clustering seen so far! HiRes-I Monocular Data, E > 1018.5 eV Upper limit of 4 doublets (90% c.l.) in HiRes-I monocular dataset. HiRes Stereo
CRs at the Highest Energies can traverse longer distances than photons can point back to the source should have spectral features
-resonance multi-pions High Energy Proton sees Cosmic Microwave Background as High Energy Gamma Rays! WMAP p+cmb + p + 0 n + + Proton Horizon GZK Cutoff Greisen ‘66, Zatsepin & Kuzmin ‘66
GZK feature is source & B dependent… E. Parizot et al. ‘03
AGASA High Energy Spectrum AGASA: ~ 11 events above 1020 eV!!!
Statistics Fluctuations at GZK feature are large for AGASA & HiRes 400 realizations of GZK feature for low statistics DeMarco, Blasi, & A.O. ‘03
Auger (S) x AGASA DeMarco, Blasi, A.O. ‘03
Pierre Auger Project • 2 Giant AirShower Arrays • South – Argentina Funded • North – Not Yet Funded • 1600 particle detectors over • 3000 km2 • + 4 Fluorescence Detectors • Will Measure Direction, • Energy, & Composition of • ~ 60 events/yr E > 1020eV • ~ 6000 events/yr E > 1019eV > 250 scientists from 16 countries Vietnam! J. Cronin and T. Yamamoto