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Attempts to explain CMB Large-scale Anomalies Kin-Wang Ng ( 吳建宏 ) Academia Sinica, Taiwan. NTU String Group, June 18, 2010. Thanks: Hsien-Chun Wu, I-Chin Wang, Da-Shin Lee, Wolung Lee, Hing-Tong Cho,Yeo-Yie Charng, Shang-Yung Wang . 7 o resolution. WMAP3 CMB sky map.
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Attempts to explain CMB Large-scale AnomaliesKin-Wang Ng (吳建宏)Academia Sinica, Taiwan NTU String Group, June 18, 2010 Thanks: Hsien-Chun Wu, I-Chin Wang, Da-Shin Lee, Wolung Lee, Hing-Tong Cho,Yeo-Yie Charng, Shang-Yung Wang
WMAP3 CMB sky map
Low quadrupole WMAP1 WMAP3
northern hemisphere southern hemisphere full sky Eriksen et al 04 Park 04 South-North Power Asymmetry Eriksen et al 04 North pole (80o,57o)
“Axis of Evil” Land & Magueijo 05 l=2, quadrupole l=3, octopole
Size of a casually connected region (horizon -- distance travelled by light in 400,000 yrs) is about 1o now q At last scattering surface, 400,000 yrs after big-bang l = 180 degrees/ q • 7o angular scale • Each 7opixel contains many 1o regions • Measuring super-horizon temperature fluctuations • So smooth (1 in 105)!! Why?? • Primordial density fluctuations that seed large scale structures COBE DMR MAP
WMAP3 and chaotic inflation r : tenor/scalar m ~ 1013 GeV
roughness of H inflation starts here Inflation and Primordial Density Fluctuations periodic universe, more…..
Slow-roll kinematics Quantum fluctuations A Challenge to Standard Slow-roll inflation!? • Chaotic inflation – classical fluctuations driven by a white noise (Starobinsky) or by a colored noise (Liguori, Matarrese et al.) coming from high-k inflaton • Driven by a colored noise from interacting quantum environment (Wu et al) • Others • Slow-roll conditions violated after horizon crossing (Leach et al) • General slow-roll condition (Steward) |n-1|~|dn/dlnk| • Multi-field (Vernizzi, Tent, Rigopoulos, Yokoyama et al) • etc
Our Inflaton-Scalar Interacting Model (Wu et al 07) Single-field inflation〈σ〉= 0
Dissipation Noise imaginary part real part Colored, dependent on history Trace out sigma field to obtain : Feynman & Vernon 1963 Influence Functional Method semi-classical
Dominant passive fluctuations and low CMB quadrupole assuming no active de Sitter quantum fluctuations
Relative large three-point functions ns Dissipation? Conclusion I • We propose a new dynamical source for density perturbation: Colored Quantum Noise - give alow CMB quadrupole • Can be applied to trapped inflation (Green et al. 09) • Working on running spectral index and non-Gaussianity, both are natural with colored noise
A black hole in inflation Cho, Ng, Wang 09 M - black hole mass H - Hubble parameter Schwarzschild-de Sitter Static ------> Planar
Inflaton fluctuations Expansion parameter where the source term
Solutions Zero order First order
Power spectrum de Sitter quantum fluctuations End of inflation → 0
Inflation early universe present universe Possible effects to CMB anisotropy e.g. black holes formed via thermal fluctuations Chen, Gruber, Ng, Scardigli 10 Carroll, Tseng, & Wise 08 preferred point, line, or plane
Conclusion II • Hints from WMAP data on beyond standard slow-roll inflation !? • A fine tuning – physics just at 60 e-foldings • Maybe there is a window to see the first few e-foldings of inflation !? • From homogeneous to directional effects • Or we are all fooled by probability – it is indeed a Gaussian quantum process • Nongaussianity is an important check
Speculations • Is it possible not to fine tune inflation duration to 60 efolds? • Then there must be something happening during slow-roll inflation • Formation rate must not be far below the expansion rate of inflation
String Landscape • 10500 de Sitter vacua • Metastable, bubble nucleation via tunneling • Barriers of string scale, slow tunneling rate • The spacetime is a hierachy of de Sitter vacuum bubbles • Most part in eternal inflation • Some regions tunnel down to flat potential for slow-roll infaltion • We sit in a vacuum with a small cosmological constant today
slow-roll inflation in a de Sitter vauum Will these bubbles collapse into black holes? Efficient and rapid tunneling Tye, Shiu,… Λ2 Λ1
Motion of the bubble wall surface tension bubble radius