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Related papers: Observational effects from quantum cosmology

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On the one hand, inflation is an extremely convincing scenario: it solves most cosmological paradoxes and generates fluctuations that became the seeds for the growth of structures. It, however, suffers from a "naturalness" problem:…

General Relativity and Quantum Cosmology · Physics 2011-08-04 Aurelien Barrau

We analyze a quantized toy model of a universe undergoing eternal inflation using a quantum-field-theoretical formulation of the Wheeler-DeWitt equation. This so-called third quantization method leads to the picture that the eternally…

General Relativity and Quantum Cosmology · Physics 2018-03-22 João Morais , Mariam Bouhmadi-López , Manuel Kraemer , Salvador Robles-Pérez

The expansion of our universe, when followed backward in time, implies that it emerged from a phase of huge density, the big bang. These stages are so extreme that classical general relativity combined with matter theories is not able to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Martin Bojowald

One of the interesting open problems in the cosmological framework is applying quantum physics to the whole universe, consistently. Although different conceptual aspects of quantum cosmology are still very much alive, till now, all the…

General Relativity and Quantum Cosmology · Physics 2022-06-22 S. H. Hendi , N. Riazi , S. N. Sajadi

After reviewing the general ideas of quantum cosmology (Wheeler-DeWitt equation, boundary conditions, interpretation of $\psi$), I discuss how these ideas can be tested observationally. Observational predictions differ for different choices…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Alexander Vilenkin

Loop quantum cosmology is a conflicted field in which exuberant claims of observability coexist with serious objections against the conceptual and physical viability of its current formulations. This contribution presents a non-technical…

General Relativity and Quantum Cosmology · Physics 2021-06-28 Martin Bojowald

We consider a model of modified gravity from the nonperturbative quantization of a metric. We obtain the modified gravitational field equations and the modified conservational equations. We apply it to the FLRW spacetime and find that due…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Rong-Jia Yang

The Wheeler--DeWitt equation for a flat and compact Friedmann--Lema\^{i}tre--Robertson--Walker cosmology at the pre-inflation epoch is studied in the contexts of the standard and fractional quantum cosmology. Working within the…

General Relativity and Quantum Cosmology · Physics 2023-04-17 S. M. M. Rasouli , E. W. Oliveira Costa , P. V. Moniz , S. Jalalzadeh

We consider the description of cosmological dynamics from the onset of inflation by a perfect fluid whose parameters must be consistent with the strength of the enhanced quantum loop effects that can arise during inflation. The source of…

General Relativity and Quantum Cosmology · Physics 2010-04-14 N. C. Tsamis , R. P. Woodard

Informed by a quantum information perspective, we interpret cosmological expansion of space as growing entanglement between underlying degrees of freedom. In particular, we focus on inflationary cosmology, which, while being a successful…

General Physics · Physics 2021-09-10 Ashmeet Singh , Olivier Doré

Loop Quantum Gravity (L.Q.G.) is one of the two most promising tentative theory for a quantum description of gravity. When applied to the entire universe, the so-called Loop Quantum Cosmology (L.Q.C.) framework offers microscopical models…

General Relativity and Quantum Cosmology · Physics 2014-11-20 J. Grain

We review the present status of quantum-gravity phenomenology in relation to gravitational waves (GWs). The topic can be approached from two direction, a model-dependent one and a model-independent one. In the first case, we introduce some…

General Relativity and Quantum Cosmology · Physics 2021-10-07 Gianluca Calcagni

This pedagogical review aims at presenting the fundamental aspects of the theory of inflationary cosmological perturbations of quantum-mechanical origin. The analogy with the well-known Schwinger effect is discussed in detail and a…

High Energy Physics - Theory · Physics 2008-11-26 Jerome Martin

Using techniques from loop quantum gravity, the standard theory of cosmological perturbations was recently generalized to encompass the Planck era. We now apply this framework to explore pre-inflationary dynamics. The framework enables us…

General Relativity and Quantum Cosmology · Physics 2015-03-12 Ivan Agullo , Abhay Ashtekar , William Nelson

This paper discusses the problem of inflation in the context of Friedmann-Robertson-Walker Cosmology. We show how, after a simple change of variables, to quantize the problem in a way which parallels the classical discussion. The result is…

High Energy Physics - Theory · Physics 2007-05-23 Marvin Weinstein , Ratindranath Akhoury

Recent cosmic microwave background data in temperature and polarization have reached high precision in estimating all the parameters that describe the current so-called standard cosmological model. Recent results about the integrated…

In this review I consider several different issues related to inflation. I will begin with the wave function of the Universe. This issue is pretty old, but recently there were some new insights based on the theory of the self-reproducing…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Andrei Linde

We study the effects of an information-theoretically motivated nonlinear correction to the Wheeler-deWitt equation in the minisuperspace scheme for flat, $k=0$, Friedmann-Robertson-Walker (FRW) universes. When the only matter is a…

General Relativity and Quantum Cosmology · Physics 2014-11-18 Le-Huy Nguyen , Rajesh R. Parwani

We consider a quantum deformation of the wave equation on a cosmological background as a toy-model for possible trans-Planckian effects. We compute the power spectrum of scalar and tensor fluctuations for power-law inflation, and find a…

High Energy Physics - Theory · Physics 2009-11-10 Sera Cremonini

Quantum creation of Universes with compact spacelike sections that have curvature $k$ either closed, flat or open, i.e. $k=\pm1,0$ are studied. In the flat and open cases, the superpotential of the Wheeler De Witt equation is significantly…

General Relativity and Quantum Cosmology · Physics 2009-10-31 D. H. Coule , Jerome Martin