Skip to content

Bouncing unitary cosmology I. Mini-superspace general solution

Research output: Contribution to journalArticle

Standard

Bouncing unitary cosmology I. Mini-superspace general solution. / Gryb, Sean; Thebault, Karim.

In: Classical and Quantum Gravity, Vol. 36, No. 3, 035009, 18.01.2019.

Research output: Contribution to journalArticle

Harvard

APA

Vancouver

Author

Gryb, Sean ; Thebault, Karim. / Bouncing unitary cosmology I. Mini-superspace general solution. In: Classical and Quantum Gravity. 2019 ; Vol. 36, No. 3.

Bibtex

@article{d9b55f978db34d6d9e0333ca672aa020,
title = "Bouncing unitary cosmology I. Mini-superspace general solution",
abstract = "We offer a new proposal for cosmic singularity resolution based upon a quantum cosmology with a unitary bounce. This proposal is illustrated via a novel quantization of a mini-superspace model in which there can be superpositions of the cosmological constant. This possibility leads to a finite, bouncing unitary cosmology. Whereas the usual Wheeler-DeWitt cosmology generically displays pathological behaviour in terms of non-finite expectation values and non-unitary dynamics, the finiteness and unitarity of our model are formally guaranteed. For classically singular models with a massless scalar field and cosmological constant, we show that well-behaved quantum observables can be constructed and generic solutions to the universal Schr{\"o}dinger equation are singularity-free. Generic solutions of our model displays novel features including: (i) superpositions of values of the cosmological constant; (ii) universal effective physics due to non-trivial self-adjoint extensions of the Hamiltonian; and (iii) bound 'Efimov universe' states for negative cosmological constant. The last feature provides a new platform for quantum simulation of the early universe. A companion paper provides detailed interpretation and analysis of particular cosmological solutions that display a cosmic bounce due to quantum gravitational effects, a well-defined FLRW limit far from the bounce, and a semi-classical turnaround point in the dynamics of the scalar field which resembles an effective inflationary epoch.",
keywords = "bouncing cosmology, cosmological constant, problem of time, quantum cosmology, singularity resolution",
author = "Sean Gryb and Karim Thebault",
year = "2019",
month = "1",
day = "18",
doi = "10.1088/1361-6382/aaf823",
language = "English",
volume = "36",
journal = "Classical and Quantum Gravity",
issn = "0264-9381",
publisher = "IOP Publishing",
number = "3",

}

RIS - suitable for import to EndNote

TY - JOUR

T1 - Bouncing unitary cosmology I. Mini-superspace general solution

AU - Gryb, Sean

AU - Thebault, Karim

PY - 2019/1/18

Y1 - 2019/1/18

N2 - We offer a new proposal for cosmic singularity resolution based upon a quantum cosmology with a unitary bounce. This proposal is illustrated via a novel quantization of a mini-superspace model in which there can be superpositions of the cosmological constant. This possibility leads to a finite, bouncing unitary cosmology. Whereas the usual Wheeler-DeWitt cosmology generically displays pathological behaviour in terms of non-finite expectation values and non-unitary dynamics, the finiteness and unitarity of our model are formally guaranteed. For classically singular models with a massless scalar field and cosmological constant, we show that well-behaved quantum observables can be constructed and generic solutions to the universal Schrödinger equation are singularity-free. Generic solutions of our model displays novel features including: (i) superpositions of values of the cosmological constant; (ii) universal effective physics due to non-trivial self-adjoint extensions of the Hamiltonian; and (iii) bound 'Efimov universe' states for negative cosmological constant. The last feature provides a new platform for quantum simulation of the early universe. A companion paper provides detailed interpretation and analysis of particular cosmological solutions that display a cosmic bounce due to quantum gravitational effects, a well-defined FLRW limit far from the bounce, and a semi-classical turnaround point in the dynamics of the scalar field which resembles an effective inflationary epoch.

AB - We offer a new proposal for cosmic singularity resolution based upon a quantum cosmology with a unitary bounce. This proposal is illustrated via a novel quantization of a mini-superspace model in which there can be superpositions of the cosmological constant. This possibility leads to a finite, bouncing unitary cosmology. Whereas the usual Wheeler-DeWitt cosmology generically displays pathological behaviour in terms of non-finite expectation values and non-unitary dynamics, the finiteness and unitarity of our model are formally guaranteed. For classically singular models with a massless scalar field and cosmological constant, we show that well-behaved quantum observables can be constructed and generic solutions to the universal Schrödinger equation are singularity-free. Generic solutions of our model displays novel features including: (i) superpositions of values of the cosmological constant; (ii) universal effective physics due to non-trivial self-adjoint extensions of the Hamiltonian; and (iii) bound 'Efimov universe' states for negative cosmological constant. The last feature provides a new platform for quantum simulation of the early universe. A companion paper provides detailed interpretation and analysis of particular cosmological solutions that display a cosmic bounce due to quantum gravitational effects, a well-defined FLRW limit far from the bounce, and a semi-classical turnaround point in the dynamics of the scalar field which resembles an effective inflationary epoch.

KW - bouncing cosmology

KW - cosmological constant

KW - problem of time

KW - quantum cosmology

KW - singularity resolution

UR - http://www.scopus.com/inward/record.url?scp=85060201973&partnerID=8YFLogxK

U2 - 10.1088/1361-6382/aaf823

DO - 10.1088/1361-6382/aaf823

M3 - Article

VL - 36

JO - Classical and Quantum Gravity

JF - Classical and Quantum Gravity

SN - 0264-9381

IS - 3

M1 - 035009

ER -