INFLATION in 1090 Causally Disconnected Regions / 105 !!!
Total Page:16
File Type:pdf, Size:1020Kb
Quantum Origin of the Universe Structure V. Mukhanov ASC, LMU, München Blaise Pascal Chair, ENS, Paris Before 1990 The Universe expands Hubble law v r 1 r Hr t : : 13,7bil. years v H There exists background radiation with the temperature T 3K Penzias, Wilson 1965 There is baryonic matter: about 25% of 4He, D....heavy elements Dark Matter???? baryonic origin??? Large Scale Structure: clusters of galaxies! Filaments, Voids?????????????????????? After 90 - present COBE 1992 2.725K Blackbody Spectrum of the CMB Space-Bases experiments: Relikt-1, COBE, WMAP, Planck Balloon: Boomerang, Maxima, Archeops, EBEX, ARCADE, QMAP, Spider, TopHat Ground-based: ABS, ACBAR, ACT, AMI, APEX, APEX-SZ, ATCA BICEP, BICEP2, BIMA, CAPMAP, CAT, CBI, Clover, COSMOSOMAS, DASI, FOCUS, GUBBINS, Keck Array, MAT, OCRA, OVRO, POLARBEAR, QUaD, QUBIC, QUIET, RGWBT, Sakaatoon, SPT, TOCO, SZA, Tenerife, VSA Expanding Universe: Facts Today: The Universe is homogeneous and isotropic on scales from 300 millions up to 13 billions light-years There exist structure on small scales: Planets, Stars, Galaxies, Clusters of galaxies Superclusters .... There is 75%H , 25% He a nd heavy elements in very small amounts In past the Universe was VERY hot There exist Dark Matter and Dark Energy When the Universe was about 1000 times smaller, it was extremely homogeneous and isotropic in all scales 105 a 1 T a a When the Universe was 1000 times smaller its temperature was about 2725K Nucleosynthesis Recombination ??? Quark-gluon Neutrinos decoupling, phase transition Electron-Positron pairs annihilation ( 1 sek) 10-4 sec t 1010 Electro-weak phase transition Very homogeneous Inhomogeneous ??? INFLATION In 1090 causally disconnected regions / 105 !!! . Why? 33 lc 10 cm L 103 cm L a Initial speed of expansion i a lc 0 speed of expansion today ai Reason: Gravitation is attractive force 1 a0 Assumption: Gravity was REPULSIVE during during some time interval in very early Universe a& / a& 1 NO Problem i 0 INFLATION is the stage of accelerated expansion in the very early Universe a decelerated Friedmann Expansion a0 INFLATION ai ti t0 t cti pot E 1000000009 0 1 0 E kin 1000000003 0 Ekin 3 1000000000 E pot 9 1000000000 Prediction of inflation ! How gravity can become "repulsive"? 4G aa 3pa energy acceleration 3 density pressure Only if +3pa 0 0 "antigravity" Scenarios ??????????????????????????????????????????? Energy density , pressure p p equation of stat e p for inflation p Which concrete scenario was realized ??? Quantum Fluctuations and Galaxies Inflation "wash out" all existing classical inhomogeneities and leaves classical desert Where the ihhomogeneities come from? p x h There always exist unavoidable Quantum Fluctuations Quantum fluctuations in the density distribution are large (10-5 ) only in extremely small scales ( : 10-33 cm), -58 25 but very small ( : 10 ) on galactic scales ( : 10 cm) Can we transfer the large fluctuations from extremely small scales to large scales??? Yes!!! but only if in past the Universe went through the stage of accelerated expansion (inflation) Consider plane wave perturbation: ,expikcom x For given kcom, ph( cm ) a / k com a ( t ) and the change of the amplitude with time depends on how big is phys compared to the curvature scale (size of Einstein lift) H1 a/ a H 1 H 1 1 p / 1/ 2 , 2 3 h k k 1n 2 3 S ln / or nS 0.96 hkk Scalar perturbations Gravity waves 11 1/ 2 1/ 2 H H phys 2 p1 d p kO3 1 nS 1 k 3 1 3 1 0.950n1/ p dlnPl 0.09 7 k HaS k Ha k Ha 1/ 2 Tp O11k Ha S Small-scale spectrum: summer 2011 1 0.02 Dark Matter & Dark Energy Inflation: limits from spectrum • All predictions so far consistent with CMB. Big goal: is index <1? The spectral index is still 3 sigma away. Latest from WMAP + SPT: ns = 0.966 ± 0.011 • Running index, find dns/dlnk = -0.024 ± 0.015 (ACT+WMAP+BAO+H0, similar with SPT) • New upper limit on tensors, find (95% CL, ACT+WMAP+BAO+H0) r < 0.19 r < 0.25 Dunkley et al. 2011 CURRENT PLANCK FORECAST OBSERVATIONS TE E "In models with the initial superdense de Sitter state ... such a large amount of relic gravitational waves is generated ...that ... the very existence of this state can be experimentally" verified in the near future. (Starobinsky, 1980).