ACP Seminar (Astronomy - Cosmology - Particle Physics)

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.