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

WMAP1 WMAP3 Low quadrupole

South-North Power Asymmetry Eriksen et al 04 Park 04 North pole (80 o,57 o ) northern hemisphere southern hemisphere full sky

“Axis of Evil” Land & Magueijo 05 l=2, quadrupole l=3, octopole

Foreground problem??

At last scattering surface, 400,000 yrs after big-bang Size of a casually connected region (horizon -- distance travelled by light in 400,000 yrs) is about 1 o now COBE DMR MAP 7 o angular scale Each 7 o pixel contains many 1 o regions Measuring super-horizon temperature fluctuations So smooth (1 in 10 5 )!! Why?? Primordial density fluctuations that seed large scale structures  l = 180 degrees / 

Inflation and Primordial Density Fluctuations

WMAP3 and chaotic inflation r : tenor/scalar m ～ GeV

Inflation and Primordial Density Fluctuations roughness of H inflation starts here periodic universe, more…..

H

A Challenge to Standard Slow-roll inflation!? Slow-roll kinematics Quantum fluctuations 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 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

Our Inflaton-Scalar Interacting Model Single-field inflation 〈 σ 〉 = 0 (Wu et al 07)

Trace out sigma field to obtain : Colored, dependent on history Dissipation Noise imaginary partreal part Feynman & Vernon 1963 Influence Functional Method semi-classical

Start of inflation

Dominant passive fluctuations and low CMB quadrupole assuming no active de Sitter quantum fluctuations

Conclusion I We propose a new dynamical source for density perturbation: Colored Quantum Noise - give a low 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 Relative large three-point functions nsns Dissipation?

A black hole in inflation Cho, Ng, Wang 09 Schwarzschild-de Sitter M - black hole mass H - Hubble parameter 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

Possible effects to CMB anisotropy Carroll, Tseng, & Wise 08 preferred point, line, or plane Inflation present universe early universe e.g. black holes formed via thermal fluctuations Chen, Gruber, Ng, Scardigli 10

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 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

Efficient and rapid tunneling slow-roll inflation in a de Sitter vauum Will these bubbles collapse into black holes? Tye, Shiu,… Λ1Λ1 Λ2Λ2

Motion of the bubble wall surface tension bubble radius