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Related papers: New Results in One-Loop Quantum Cosmology

200 papers

We consider two-dimensional quantum gravity endowed with a positive cosmological constant and coupled to a conformal field theory of large and positive central charge. We study cosmological properties at the classical and quantum level. We…

High Energy Physics - Theory · Physics 2025-03-05 Dionysios Anninos , Chiara Baracco , Beatrix Mühlmann

A general method exists for studying Abelian and non-Abelian gauge theories, as well as Euclidean quantum gravity, at one-loop level on manifolds with boundary. In the latter case, boundary conditions on metric perturbations h can be chosen…

High Energy Physics - Theory · Physics 2007-05-23 Giampiero Esposito , Guglielmo Fucci , Alexander Yu. Kamenshchik , Klaus Kirsten

This paper studies the normalizability criterion for the one-loop wave function of the universe in a de Sitter background, when various unified gauge models are considered. It turns out that, in the absence of interaction between inflaton…

High Energy Physics - Theory · Physics 2009-10-30 Giampiero Esposito , Alexander Yu. Kamenshchik , Gennaro Miele

We do not yet know how to quantize gravity in 3+1 dimensions, but in lower dimensions we face the opposite problem: many of the approaches originally developed for (3+1)-dimensional gravity can be successfully implemented in 2+1 dimensions,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Carlip

Gravity is perturbatively renormalizable for the physical states which can be conveniently defined via foliation-based quantization. In recent sequels, one-loop analysis was explicitly carried out for Einstein-scalar and Einstein-Maxwell…

High Energy Physics - Theory · Physics 2021-11-12 I. Y. Park

The wavefunctional in quantum gravity gives an amplitude for 3-geometries and matter fields. The four-space is usually recovered in a semiclassical approximation where the gravity variables are taken to oscillate rapidly compared to matter…

General Relativity and Quantum Cosmology · Physics 2011-09-09 Esko Keski-Vakkuri , Samir D. Mathur

We study the most elementary aspects of harmonic analysis on a homogeneous space of a deformation of the two-dimensional Euclidean group, admitting generalizations to dimensions three and four, whose quantum parameter has the physical…

q-alg · Mathematics 2008-02-03 F. Bonechi , R. Giachetti , M. A. del Olmo , E. Sorace , M. Tarlini

Several approaches to the dynamics of loop quantum gravity involve discretizing the equations of motion. The resulting discrete theories are known to be problematic since the first class algebra of constraints of the continuum theory…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Rodolfo Gambini , Jorge Pullin

The problem of finding the quantum theory of the gravitational field, and thus understanding what is quantum spacetime, is still open. One of the most active of the current approaches is loop quantum gravity. Loop quantum gravity is a…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Carlo Rovelli

We study two-dimensional quantum gravity on arbitrary genus Riemann surfaces in the Kaehler formalism where the basic quantum field is the (Laplacian of the) Kaehler potential. We do a careful first-principles computation of the fixed-area…

High Energy Physics - Theory · Physics 2015-12-09 Adel Bilal , Laetitia Leduc

First, we review the $C^\ast$-algebraic foundations of loop quantization, in particular, the construction of quantum configuration spaces and the implementation of symmetries. Then, we apply these results to loop quantum gravity, focusing…

Mathematical Physics · Physics 2015-07-21 Christian Fleischhack

Two approaches to quantization of Freedman's closed Universe are compared. In the first approach, the Shrodinger's norm of the wave function of Universe is used, and in the second approach, the Klein-Gordon's norm is used. The second one…

General Relativity and Quantum Cosmology · Physics 2008-01-03 K. A. Viarenich , V. L. Kalashnikov , S. L. Cherkas

We here calculate the one-loop approximation to the Euclidean Quantum Gravity coupled to a scalar field around the classical Carlini and Miji\'c wormhole solutions. The main result is that the Euclidean partition functional $Z_{EQG}$ in the…

High Energy Physics - Theory · Physics 2010-04-06 Alberto Carlini , Maurizio Martellini

In non-supersymmetric covariant quantum gravity theory, for each system of gravity coupled with single field is one-loop divergent. Since adding other fields or other interactions to each system generates more possible counter-Lagrangian…

High Energy Physics - Theory · Physics 2017-12-12 Hyun Ju Go

Motivated by the dark energy issue, the one-loop quantization approach for a family of relativistic cosmological theories is discussed in some detail. Specifically, general $f(R)$ gravity at the one-loop level in a de Sitter universe is…

High Energy Physics - Theory · Physics 2009-09-17 Guido Cognola , Emilio Elizalde , Shin'ichi Nojiri , Sergei D. Odintsov , Sergio Zerbini

We construct a spinning particle that reproduces the propagation of the graviton on those curved backgrounds which solve the Einstein equations, with or without cosmological constant, i.e. Einstein manifolds. It is obtained by modifying the…

High Energy Physics - Theory · Physics 2021-02-24 Fiorenzo Bastianelli , Roberto Bonezzi , Olindo Corradini , Emanuele Latini

Quantum Reduced Loop Gravity is a promising framework for linking Loop Quantum Gravity and the effective semiclassical dynamics of Loop Quantum Cosmology. We review its basic achievements and its main perspectives, outlining how it provides…

General Relativity and Quantum Cosmology · Physics 2016-08-03 Emanuele Alesci , Francesco Cianfrani

In this PhD thesis, we introduced a new strategy to investigate the kinematical and physical predictions of self dual Loop Quantum Gravity (LQG) and by-passed the old problem of implementing quantum mechanically the so called reality…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Jibril Ben Achour

Building upon our recently established correspondence between quantum cosmology and the hydrogen atom [1], we investigate the specific sector of a negative cosmological constant ($\Lambda < 0$) in a flat FLRW universe with dust. While the…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Dipayan Mukherjee , Harkirat Singh Sahota , S. Shankaranarayanan

We summarize our work on spherically symmetric midi-superspaces in loop quantum gravity. Our approach is based on using inhomogeneous slicings that may penetrate the horizon in case there is one and on a redefinition of the constraints so…

General Relativity and Quantum Cosmology · Physics 2025-05-14 Rodolfo Gambini , Javier Olmedo , Jorge Pullin