Speaker: |
Andrei Barvinsky (Lebedev Inst.) |
Title: |
Density matrix of the universe and the CFT driven cosmology |
Date (JST): |
Tue, Nov 27, 2012, 15:30 - 16:30 |
Place: |
Seminar Room A |
Related File: |
802.pdf
|
Abstract: |
Cosmological initial conditions in the form of the microcanonical density matrix are suggested and applied to cosmological model driven by a conformal field theory (CFT) -- quantum matter conformally coupled to gravity. Euclidean qantum gravity path integral for its statistical sum incorporates the both known no-boundary and tunneling prescriptions for a quantum state of the Universe and by a dynamical mechanism of the quantum conformal anomaly turns out to be dominated by the periodic cosmological instantons which can be regarded as the thermal version of the Hartle-Hawking instantons. These instantons exist in the bounded range of the primordial cosmological constant and give rise to inflationary universes with a thermal nature of the primordial power spectrum of cosmological perturbations. This suggests a new mechanism for the red tilt of the CMB anisotropy, complementary to the conventional mechanism based on a small deviation of the inflationary expansion from the exact de Sitter evolution. The analogue of holographic duality of this model to the 5-dimensional brane-induced gravity model is also briefly discussed. |