Open quantum cosmological system
Abstract
We derive the evolution equation for the density matrix of a UV- and IR- limited band of comoving momentum modes of the canonically normalized scalar degree of freedom in two examples of nearly de Sitter universes. Including the effects of a cubic interaction term from the gravitational action and tracing out a set of longer wavelength modes, we find that the evolution of the system is non-Hamiltonian and non-Markovian. We find linear dissipation terms for a few modes with wavelength near the boundary between system and bath, and nonlinear dissipation terms for all modes. The non-Hamiltonian terms in the evolution equation persist to late times when the scalar field dynamics is such that the curvature perturbation continues to evolve on super-Hubble scales.
- Publication:
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Physical Review D
- Pub Date:
- October 2018
- DOI:
- 10.1103/PhysRevD.98.083535
- arXiv:
- arXiv:1708.00493
- Bibcode:
- 2018PhRvD..98h3535S
- Keywords:
-
- High Energy Physics - Theory;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Quantum Physics
- E-Print:
- 5 pages