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Related papers: Time Evolution in Quantum Cosmology

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A set of diverse but mutually consistent results obtained in different settings has spawned a new view of loop quantum gravity and its physical implications, based on the interplay of operator calculations and effective theory: Quantum…

General Relativity and Quantum Cosmology · Physics 2012-12-27 Martin Bojowald

Quantum gravity places entirely new challenges on the formulation of a consistent theory as well as on an extraction of potentially observable effects. Quantum corrections due to the gravitational field are commonly expected to be tiny…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald

The paper is the first of two parts of a work reviewing some approaches to the problem of time in quantum cosmology, which were put forward last decade, and which demonstrated their relation to the problems of reparametrization and gauge…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. P. Shestakova , C. Simeone

Familiar textbook quantum mechanics assumes a fixed background spacetime to define states on spacelike surfaces and their unitary evolution between them. Quantum theory has changed as our conceptions of space and time have evolved. But…

General Relativity and Quantum Cosmology · Physics 2008-06-09 James B. Hartle

Without wasting time and effort on philosophical justifications and implications, we write down the conditions for the Hamiltonian of a quantum system for rendering it mathematically equivalent to a deterministic system. These are the…

Quantum Physics · Physics 2020-06-09 Gerard t Hooft

This thesis contains an analysis of the problem of time in quantum cosmology and its application to a cosmological minisuperspace model. In the first part, we introduce the problem of time and the theoretical foundations. In the second…

General Relativity and Quantum Cosmology · Physics 2022-11-18 Lucía Menéndez-Pidal

We show that if a discrete quantum gravity is not classical, then it cannot be generated by an isometric dynamics. In particular, we show that if the quantum measure {\mu} (or equivalently the decoherence functional) is generated by an…

General Relativity and Quantum Cosmology · Physics 2011-12-06 Stan Gudder

Quantum dynamics of coherent states is studied within quantum field theory using two complementary methods: by organizing the evolution as a Taylor series in elapsed time and by perturbative expansion in coupling within the…

High Energy Physics - Theory · Physics 2021-10-13 Lasha Berezhiani , Michael Zantedeschi

We propose a mathematical structure, based on a noncommutative geometry, which combines essential aspects of general relativity and quantum mechanics, and leads to correct "limiting cases" of both these theories. We quantize a groupoid…

General Relativity and Quantum Cosmology · Physics 2009-10-30 M. Heller , W. Sasin

The covariant canonical transformation theory applied to the relativistic Hamiltonian theory of classical matter fields in dynamical space-time yields a novel (first order) gauge field theory of gravitation. The emerging field equations…

General Relativity and Quantum Cosmology · Physics 2023-11-29 David Vasak , Johannes Kirsch , Dirk Kehm , Juergen Struckmeier

Isotropic models in loop quantum cosmology allow explicit calculations, thanks largely to a completely known volume spectrum, which is exploited in order to write down the evolution equation in a discrete internal time. Because of genuinely…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Martin Bojowald

For a quantum field living on a non - static spacetime no instantaneous Hamiltonian is definable, for this generically necessitates a choice of inequivalent representation of the canonical commutation relations at each instant of time. This…

General Relativity and Quantum Cosmology · Physics 2011-07-19 C. Anastopoulos

In this thesis we consider the problem of dynamics in canonical loop quantum gravity, primarily in the context of deparametrized models, in which a scalar field is taken as a physical time variable for the dynamics of the gravitational…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ilkka Mäkinen

We provide a new perspective on non-Hermitian evolution in quantum mechanics by emphasizing the same method as in the Hermitian quantum evolution. We first give a precise description of the non unitary evolution, and collecting the basic…

Quantum Physics · Physics 2017-07-21 Mustapha Maamache

We analyze the dynamics of the gravitational field when the covariance is restricted to a synchronous gauge. In the spirit of the Noether theorem, we determine the conservation law associated to the Lagrangian invariance and we outline that…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Giovanni Montani , Francesco Cianfrani

We analize the relational quantum evolution of generally covariant systems in terms of Rovelli's evolving constants of motion and the generalized Heisenberg picture. In order to have a well defined evolution, and a consistent quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rodolfo Gambini , Rafael A. Porto

In this paper canonical quantum gravity on noncommutative space-time is considered. The corresponding generalized classical theory is formulated by using the moyal star product, which enables the representation of the field quantities…

General Relativity and Quantum Cosmology · Physics 2016-09-02 Martin Kober

We reexamine the relationship between the path integral and canonical formulation of quantum general relativity. In particular, we present a formal derivation of the Wheeler-DeWitt equation from the path integral for quantum general…

General Relativity and Quantum Cosmology · Physics 2017-11-15 Justin C. Feng , Richard A. Matzner

In this paper we consider generalization of classical and quantum mechanics that directly follows from the causality principle and topology of a system state space. In generalized mechanics, the Hamiltonian/Schrodinger equations remain the…

General Physics · Physics 2022-04-04 Uziel Sandler

We explore the consequences of allowing non-Hermitian structures in quantum cosmology by extending the Wheeler DeWitt framework beyond strictly Hermitian dynamics. Using a controlled semiclassical reduction, we show how anti Hermitian…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-06 Oem Trivedi , Alfredo Gurrola