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WMAP が開く量子重力的宇宙像

3/5, 2004 at KEK. WMAP が開く量子重力的宇宙像. Based on CMB Anisotropies Reveal Quantized Gravity By 湯川 哲之 ( 総研大 ) and K.H. astro-ph/0401070. KEK 浜田賢二. 2. Anisotropies in the CMB. COBE (1996). WMAP (2003). 3. Angular Power Spectrum.

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WMAP が開く量子重力的宇宙像

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  1. 3/5, 2004 at KEK WMAPが開く量子重力的宇宙像 Based on CMB Anisotropies Reveal Quantized Gravity By 湯川 哲之 (総研大) and K.H. astro-ph/0401070 KEK 浜田賢二

  2. 2 Anisotropies in the CMB COBE (1996) WMAP (2003)

  3. 3 Angular Power Spectrum Angular Power Spectrum at Ultra Super-Horizon (l<40) Region Sachs-Wolfe effect with Harrison-Zel’dovich spectrum l(l+1)Cl l(l+1)Cl HZspectrum 40 2 l 2 40 l Large deviation at l=2

  4. 4 No scale (except deSitter scale) Harrison-Zel’dovich spectrum Dynamical scales deform HZ spectrum sound speed acoustic peak spatial curvature Sharpe damping at large angle can be explained by cosmic variance ? No, it indicates new dynamical scale!

  5. 5 Because cosmic variance is based on Ergodic Hypothesis (2l+1) Ensemble of sub-Universe statistical error of : But, at super-horizon region two points causally disconnected Not Ergodic Initial quantum fluctuations will be preserved for super-horizon separation

  6. 6 If we believe the idea of inflation, CMB anisotropies provide us information about dynamics beyond the Planck scale. Dynamical scale of Quantum Gravity NB. Trans-Plankian problem: Necessary to solve flatness problem universe inflation a: scale factor

  7. 7 Contents • Introduction • Why Quantum Gravity is necessary • 3. The Renormalizable Model • 4. New Dynamical Scenario of Inflation • 5. Primordial Power Spectrum • 6. Further Discussions about Dynamical Scale • Big bang scenario • Black hole physics • etc • 7. Conclusions and Future Projects

  8. 8 2. Why Quantum Gravity is necessary • Singularity in BH and early universe • divergence/non-calculability • information loss • Breakdown of particle picture • A excitation with the Planck massBH Heisenberg uncertainty Schwarzshild radius cf. Proton mass, m

  9. 9 Spacetime fluctuates greatly loss of the concept of distance = background-metric independence No scales /No singularity Dynamical scale generates classical spacetime 量子重力は特定の時空の上の場の量子論ではなく、 時空のゆらぎそのものを記述するものでなければならない。 同時に、いわゆる我々の時空を生成するダイナミクス を含むものでなければならない。

  10. 10 3. The Renormalizable Model Limitation of Einstein theory • non-renormalizable • singular spacetime configs. cannot be removed (Here, Euclidean is considered) Conformal weight Weyl tensor Singularity removed !

  11. 11 TheRenormalizable Gravity conformal invariant 4-derivative actions sgn=(-1,1,1,1) The metric fields in strong gravity phase conformal mode traceless mode : The coupling constant for traceless mode : Weyl tensor = field strength of traceless mode : Topological density : Mater actions ( scalar , fermion ,vector )

  12. 12 Conformal mode is treated non-perturbatively The partition function Jacobian = Wess-Zumino action Dynamics of conformal mode is induced from the measure: Conformal Field Theory (CFT) Higher order of the coupling conformal inv : , and thus

  13. Dynamics of the Traceless Mode 13 Asymptotically Free Dynamical Scale of Gravity Runningcouplingconstant At very high energies , the coupling vanishes and conformal mode dominates => CFT ※This also implies that background-metric independence for traceless mode is less important.

  14. 14 Renormalization (QED + gravity) Beta functions where : coeff. of WZ action of type New WZ actions (=new vertices) like are induced at higher orders Conformal mode is not renormalized : K.H. hep-th/0203250

  15. 15 Simplicial Quantum Gravity support Renormalizable Gravity String susceptibility Two Point Correlation Horata, Egawa, Yukawa, hep-lat/0209004

  16. 4. New Dynamical Scenario of Inflation 16 Order of Mass Scales At very high energies : Conformal mode dominates => CFT Wess-Zumino action (=Jacobian) where conf. inv. 4-th order op. :

  17. 17 CFT + Einstein term For : Conformal mode fluctuates greatly around inflating solution of E.O.M: where : proper time

  18. 18 For : The coupling diverges : Interactions become short range and effective action changes drastically At , inflation terminates and Einstein spacetime is generated The number of e-foldings : Large number of e-foldings can be obtained

  19. 19 Summary of the model E Background-metric independent spacetime No singularity Described by CFT (long range) Quantum spacetime Inflation era (still long range) The traceless-mode coupling gets large, and correlation becomes short range: Friedmann era ordinary particles are described as excitations around classical spacetime: graviton, photons, fermions. Classical spacetime De Sitter again

  20. 5. Primordial Power Spectrum 20 WMAP observes quantum fluctuations of scalar curvature just before quantum spacetime transits to classical spacetime at spectrum deformed by scales transition to classical spacetime Power spectrum = Two-point correlation

  21. 21 Two-point correlation of scalar curvature is calculated by CFT Scaling dimension of curvature anomalous dimensions by CFT Annomalous dimension by the traceless mode dynamics Two-point correlation function: Physical distance

  22. 22 Angular Power Spectrum: Legendre polynomials = Using the relations: Poisson eq. Friedmann eq. Sachs-Wolfe relation and our proposal: : comoving wavenumber at , or

  23. 23 We finally obtain with running coupling effect where :spectral index by CFT : comoving dynamical scale : comoving Planck constant Number of e-foldings :

  24. 24 Sharp damping at l=3 comoving dynamical scale If we take WMAP data n=1.3 1.2 1.1

  25. 25 Scales Planck scale: Large number of e-foldings is necessary for solving the flatness problem If Dynamical scale : scale factor :

  26. 26 WMAP suggests blue spectrum (n > 1) at large angle Quantum gravity scenario predicts large blue spectrum at large angle : Standard Model This value seems to large compared with observed spectrum Extra fields/dark matters? • GUT ( n=1.28 for SU(5)) • SUSY • etc Violation of background-metric indep. =violation of superconformal sym.?

  27. 27 WMAP suggests red (n < 1) for small angle We have assumed that the unique decoupling time, , for entire momentum range. However, if there is a time lag in the phase transition, short scale delay will change to be an increasing function of the comoving wavenumber. Peiris et al astro-ph/0302225

  28. 6. Further Discussions about 28 How did the Big Bang start? The traceless mode coupling becomes large and Interactions turn to short range . Then, the conformal mode freezes to classical spacetime. The field fluctuation percolates to localized object: graviball with mass decay to ordinary matters Thermal equilibrium / Big bang

  29. 29 Model for the strong interactions At higher order, new interactions (like , ) are induced from the measure Effective action is modified and Inflation terminates to Friedmann universe ! How to determine effective action ? Initial condition = CFT Final condition = Friedmann Sharp transition at :continuum or discrete etc.

  30. 30 How the information loss problem is solved? Unitarity problem in strong gravity phase Physical excitations in strong gravity/CFT phase are no longer ordinary particles. The physical observable is not S-matrix, but statistical exponents of correlation functions. Power spectrum Unitarity implies the positivity of the statistical weight. To prove unitarity, need detailed structure of physical states. Classification of rep. of conformal algebra

  31. 31 Modification of Einstein theory After conformal mode freezes to classical spacetime, weak field approximation (expansion by G) becomes effective. Note that Here, take Full propagator of the traceless mode : No tachyon condition correction (no ghost pole) normalization removed graviton pole cf. gauge theories and independent

  32. 32 Low energy effective action . . . : matter current and stress-tensor

  33. 33 Black hole picture changes Horizon would disappear for tiny black hole obtained at final stage of evaporation No singularity solve information loss problem? horizon r • WMAP data • Determination of strong coupling effective action • Study of BH structure 0 strong coupling of traceless mode classical spacetime CFT

  34. 34 7. Conclusions and Future projects • Quantum gravity scenario of inflation was given. • Sharp damping of the power spectrum at low multipoles • was explained by dynamical scale of quantum gravity. • Large blue spectrum at large angle was predicted. • Tensor/scalar ratio is negligible, because of the conformal • mode dominance. A great advantage of this QG model is that it ignites the inflation naturally without any additional fields

  35. 35 Future projects • Full analysis of angular power spectrum • Need a model for strong • Analysis of multi-point correlation/bi-spectrum • PLANCK mission (2007) Non-Gaussianity WMAP: By Komatsu et al Standard models of inflation : Theoretical consistency Experimental test

  36. 36 Cosmology WMAP/PLANCK 4D CFT/ Non-critical 3-Brane Renormalizable 4DQuantumGravity Black Hole Physics Random Surface/ Lattice Gravity Particle Physics

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