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Related papers: Metric fluctuations in semiclassical gravity

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We describe a kinetic theory approach to quantum gravity -- by which we mean a theory of the microscopic structure of spacetime, not a theory obtained by quantizing general relativity. A figurative conception of this program is like…

General Relativity and Quantum Cosmology · Physics 2008-11-26 B. L. Hu

We investigate the problem of metric fluctuations in the presence of the vacuum fluctuations of matter fields and critically assess the usual assertion that vacuum energy implies a Planckian cosmological constant. A new stochastic classical…

General Relativity and Quantum Cosmology · Physics 2008-06-19 Charles H. -T. Wang , Paolo M. Bonifacio , Robert Bingham , J. Tito Mendonca

In this talk we will argue that, when gravitons are taken into account, the solution to the semiclassical Einstein equations (SEE) is not physical. The reason is simple: any classical device used to measure the spacetime geometry will also…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Diego A. R. Dalvit , Francisco D. Mazzitelli

We discuss Einstein-Klein-Gordon system in an environment of an infinite number of scalar fields leading to an external thermal noise. In the lowest order of metric and field perturbations the quadratic fluctuations consist of a sum of…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Z. Haba

Semiclassical gravity couples classical gravity to the quantized matter in meanfield approximation. The meanfield coupling is problematic for two reasons. First, it ignores the quantum fluctuation of matter distribution. Second, it violates…

General Relativity and Quantum Cosmology · Physics 2025-05-28 Lajos Diósi

The continual production of long wavelength gravitons during primordial inflation endows graviton loop corrections with secular growth factors. During a prolonged period of inflation these factors eventually overwhelm the small…

General Relativity and Quantum Cosmology · Physics 2024-09-19 S. P. Miao , N. C. Tsamis , R. P. Woodard

Semiclassical gravity, in which a classical spacetime is sourced by the quantum expectation value of the stress-energy tensor, is a standard framework for describing the gravitational interaction of quantum matter. In the nonrelativistic…

General Relativity and Quantum Cosmology · Physics 2025-12-23 Hollis Williams

It is shown that if the Euclidean path integral measure of a minimally coupled free quantum scalar field on a classical metric background is interpreted as probability of observing the field configuration given the background metric then…

Quantum Physics · Physics 2021-02-22 Can Gokler

A fluctuation-dissipation relation for perturbed configuration of a relativistic star is obtained. The stochastic fluctuations of the classical stress tensor comprising the matter content ( a perfect fluid) of the relativistic star, act as…

General Relativity and Quantum Cosmology · Physics 2020-04-02 Seema Satin

It is supposed the alternative to Quantum Mechanics Axiomatic. Fluctuational Theory save the Mathematics of Quantum Mechanic without change, naming this Mathematics as Method of Indirect Computation. Fluctuational Theory is delete the…

Quantum Physics · Physics 2007-05-23 Timur F. Kamalov

Fully covariant wave equations predict the existence of a class of inertial-gravitational effects that can be tested experimentally. In these equations inertia and gravity appear as external classical fields, but, by conforming to general…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. Papini

A general affine connection has enough degrees of freedom to describe the classical gravitational and electromagnetic fields in the metric-affine formulation of gravity. The gravitational field is represented in the Lagrangian by the…

General Relativity and Quantum Cosmology · Physics 2008-03-03 Nikodem J. Poplawski

A stochastic dynamics has a natural decomposition into a drift capturing mean rate of change and a martingale increment capturing randomness. They are two statistically uncorrelated, but not necessarily independent mechanisms contributing…

Statistical Mechanics · Physics 2021-06-28 Ying-Jen Yang , Hong Qian

We propose a quantitative test for the validity of the semi-classical approximation in gravity, namely that the solutions to the semi-classical equations should be stable to linearized perturbations, in the sense that no gauge invariant…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Paul R. Anderson , Carmen Molina-Paris , Emil Mottola

A theory of quantum gravity consists of a gravitational framework which, unlike general relativity, takes into account the quantum character of matter. In spite of impressive advances, no fully satisfactory, self-consistent and empirically…

General Relativity and Quantum Cosmology · Physics 2025-06-23 R. Muciño , E. Okon , D. Sudarsky , M. Wiedemann

Einstein's equations in matter are gravitational analogues of Maxwell's equations in matter, providing an effective classical description of gravitational fields. We derive Einstein's equations in matter for relativistic fluids, and use…

General Relativity and Quantum Cosmology · Physics 2020-05-29 Pavel Kovtun , Ashish Shukla

Semiclassical Gravity replaces the energy momentum tensor $T_{\mu \nu}$ with its expectation value $\langle T_{\mu \nu}\rangle$ in Einstein equations, this making the Einstein tensor $G_{\mu \nu}$ a classical variable thus avoiding the…

Quantum Physics · Physics 2018-11-28 Sergio De Filippo

Quantum decoherence can arise due to classical fluctuations in the parameters which define the dynamics of the system. In this case decoherence, and complementary noise, is manifest when data from repeated measurement trials are combined.…

General Relativity and Quantum Cosmology · Physics 2011-09-13 G. J. Milburn

In this paper, we generalize the theory of Brownian motion and the Onsager-Machlup theory of fluctuations for spatially symmetric systems to equilibrium and nonequilibrium steady-state systems with a preferred spatial direction, due to an…

Statistical Mechanics · Physics 2016-09-28 Roman Belousov , E. G. D. Cohen , Lamberto Rondoni

A mathematical derivation of Maxwell's equations for gravitation, based on a mathematical proof of Faraday's Law, is presented. The theory provides a linear, relativistic Lagrangian field theory of gravity in a weak field, and paves the way…

General Physics · Physics 2013-05-30 D. H. Sattinger