Citation

BibTex format

@article{Gielen:2023:10.1103/physrevd.107.023518,
author = {Gielen, S and Magueijo, J},
doi = {10.1103/physrevd.107.023518},
journal = {Physical Review D},
pages = {1--16},
title = {Quantum analysis of the recent cosmological bounce in the comoving Hubble length},
url = {http://dx.doi.org/10.1103/physrevd.107.023518},
volume = {107},
year = {2023}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - We formulate the transition from decelerated to accelerated expansion as a bounce in connection space and study its quantum cosmology, knowing that reflections are notorious for bringing quantum effects to the fore. We use a formalism for obtaining a time variable via the demotion of the constants of nature to integration constants, and focus on a toy universe containing only radiation and a cosmological constant Λ for simplicity. We find that, beside the usual factor-ordering ambiguities, there is an ambiguity in the order of the quantum equation, leading to two distinct theories: one second order, and one first order. In both cases two time variables may be defined, conjugate to Λ and the radiation constant of motion. We make little headway with the second-order theory, but are able to produce solutions to the first-order theory. They exhibit the well-known “ringing” whereby incident and reflected waves interfere, leading to oscillations in the probability distribution even for well-peaked wave packets. We also examine in detail the probability measure within the semiclassical approximation. Close to the bounce, the probability distribution becomes double peaked, with one peak following a trajectory close to the classical limit but with a Hubble parameter slightly shifted downwards, and the other with a value of b stuck at its minimum. An examination of the effects still closer to the bounce, and within a more realistic model involving matter and Λ, is left to future work.
AU  - Gielen,S
AU  - Magueijo,J
DO  - 10.1103/physrevd.107.023518
EP  - 16
PY  - 2023///
SN  - 2470-0010
SP  - 1
TI  - Quantum analysis of the recent cosmological bounce in the comoving Hubble length
T2  - Physical Review D
UR  - http://dx.doi.org/10.1103/physrevd.107.023518
UR  - https://journals.aps.org/prd/abstract/10.1103/PhysRevD.107.023518
UR  - http://hdl.handle.net/10044/1/101911
VL  - 107
ER  -
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