HoravaLifshitz重力理论とはなにか.pptVIP

Horava-Lifshitz重力理論とはなにか？ 早田次郎 　京都大学理学研究科 2009.6.5 大阪市立大学セミナー T.Takahashi J.Soda, arXiv:0904.0554?[hep-th], to appear in Phys.Rev.Lett. Ref. Chiral Primordial Gravitational Waves from a Lifshitz Point Quantum fluctuations Hawking radiation Exponential red shift Quantum fluctuations BH How to get to Planck scale? In reality, it would be difficult to observe Hawking radiation. However, we may be able to observe primordial gravitational waves! Hence, in this talk, I will mostly discuss an inflation. There are two well known the paths to reach the Planck scale. inflation Exponential red shift GW The universe is so transparent for GW! Namely, one can see the very early universe! Indeed, we can indirectly observe PGW through CMB or directly observe PGW by LISA or DECIGO. What kind of smoking gun of the Planck scale can be expected? The reaction rate is much smaller than the expansion rate in the cosmic history. Hence, PGW can carry the information of the Planck scale. reaction rate expansion rate reaction rate A brief review of Inflation FRW universe dynamics deSitter universe slow roll general relativity conformal time We will consider a chaotic inflation. All of the observations including CMB data are consistent with an inflationary scenario! action for GW polarization length scale t Wavelength of fluctuations Quantum fluctuations Sub-horizon Super-horizon PGW must exist if you assume inflation! GW propagating in the z direction can be written in the TT gauge as Bunch-Davis vacuum Gravitational waves in FRW background are equivalent to two scalar fields with Power spectrum Tensor perturbation Is general relativity reliable? Planckian region Length Scale t k Initial conditions are set deep inside the horizon We are looking beyond the Planck scale! horizon size For GUT scale inflation galaxy scale We need quantum gravity!! Quantum Gravity and Renormalizability UV divergence in general relativity can not be renormalized Higher curvatur