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Title: Canonical description of cosmological backreaction
Abstract Canonical methods of quasiclassical dynamics make it possible to go beyond a strict background approximation for cosmological perturbations by including independent fields such as correlation degrees of freedom. New models are introduced and analyzed here for cosmological dynamics in the presence of quantum correlations between background and perturbations, as well as cross-correlations between different modes of a quantum field. Evolution equations for moments of a perturbation state reveal conditions required for inhomogeneity to build up out of an initial vacuum. A crucial role is played by quantum non-locality, formulated by canonical methods as an equivalent local theory with non-classical degrees of freedom given by moments of a quantum state.  more » « less
Award ID(s):
1912168
PAR ID:
10323845
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2021
Issue:
03
ISSN:
1475-7516
Page Range / eLocation ID:
083
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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