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Related papers: Barrow entropy and spacetime foam

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We consider the scenario of a fluctuating spacetime due to a deformed commutation relation with a fluctuating deformation parameter, or to a fluctuating metric tensor. By computing the resulting dynamics and averaging over these…

Quantum Physics · Physics 2025-04-01 Sandro Donadi , Matteo Fadel

The regularized vacuum fluctuation related to a conformally coupled massless scalar field defined on a space-time with dynamical horizon is computed with respect a radially moving observer in a generic flat Friedmann-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2014-04-23 Giovanni Acquaviva , Luca Bonetti , Luciano Vanzo , Sergio Zerbini

We consider implications of the microscopic dynamics of spacetime for the evolution of cosmological models. We argue that quantum geometry effects may lead to stochastic fluctuations of the gravitational constant, which is thus considered…

General Relativity and Quantum Cosmology · Physics 2022-09-15 Marco de Cesare , Fedele Lizzi , Mairi Sakellariadou

We analyze the physical meaning of fluctuations of the phase space contraction rate, that we also call entropy creation rate, and its observability in space-time intermittency phenomena. For concreteness we consider a Navier-Stokes fluid.

Chaotic Dynamics · Physics 2008-02-26 Giovanni Gallavotti

We analyze the limits that quantum mechanics imposes on the accuracy to which $(4+n)$-dimensional spacetime geometry can be measured. Using physics of computation and light sheet concept we derive explicit expressions for quantum…

High Energy Physics - Theory · Physics 2008-11-26 Pavle Midodashvili

The peculiar uncertainty or randomness of quantum measurements stems from coherence, whose information-theoretic characterization is currently under investigation. Under the resource theory of coherence, it is interesting to investigate…

Quantum Physics · Physics 2019-10-25 Xiao Yuan , Qi Zhao , Davide Girolami , Xiongfeng Ma

We consider the uncertainty in the arm length of an interferometer due to metric fluctuations from the quantum nature of gravity, proposing a concrete microscopic model of energy fluctuations in holographic degrees of freedom on the surface…

General Relativity and Quantum Cosmology · Physics 2021-10-22 Erik P. Verlinde , Kathryn M. Zurek

According to the Second Law of thermodynamics, the evolution of physical systems has a preferred direction, that is characterized by some positive entropy production. Here we propose a direct way to measure the stochastic entropy produced…

Quantum Physics · Physics 2020-11-13 Juliette Monsel , Cyril Elouard , Alexia Auffèves

The effects of fluctuating boundaries on a superposition state of a quantum particle in a box is studied. We consider a model in one space dimension in which the initial state is a coherent superposition of two energy eigenstates. The…

Quantum Physics · Physics 2012-05-11 V. A. De Lorenci , L. H. Ford

The so-called quantum measurement problems are solved from a new perspective. One of the main observations is that the basic entities of our world are {\it particles}, elementary or composite. It follows that each elementary process, hence…

Quantum Physics · Physics 2023-02-20 Kenichi Konishi

Fluctuation theorems make use of time reversal to make predictions about entropy production in many-body systems far from thermal equilibrium. Here we review the wide variety of distinct, but interconnected, relations that have been derived…

Statistical Mechanics · Physics 2007-08-02 R. J. Harris , G. M. Schütz

I explain in what sense the structure of space and time is probably vague or indefinite, a notion I define. This leads to the mathematical representation of location in space and time by a vague interval. From this, a principle of…

History and Philosophy of Physics · Physics 2023-08-24 Hanoch Ben-Yami

First the fluctuation energy is derived from the adiabatic random fluctuations due to the second-order perturbation theory, and the evolutionary relation for it is expressed in the form of rho_f = rho_f (rho), where rho and rho_f are the…

General Relativity and Quantum Cosmology · Physics 2017-09-12 Kenji Tomita

This paper delineates the first steps in a systematic quantitative study of the spacetime fluctuations induced by quantum fields in an evaporating black hole. We explain how the stochastic gravity formalism can be a useful tool for that…

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

Wheeler's conjectured "spacetime foam" -- large quantum fluctuations of spacetime at the Planck scale -- could have important implications for quantum gravity, perhaps even explaining why the cosmological constant seems so small. Here I…

General Relativity and Quantum Cosmology · Physics 2022-01-05 S. Carlip

We show that the fluctuations of quantum fields as seen by late comoving observers are significantly influenced by the history of the early Universe, and therefore they transmit information about the nature of spacetime in timescales when…

General Relativity and Quantum Cosmology · Physics 2015-10-13 Ana Blasco , Luis J. Garay , Mercedes Martin-Benito , Eduardo Martin-Martinez

We present a problem relating measurements and information theory in spin foam models. In the three dimensional case of quantum gravity we can compute probabilities of spin network graphs and study the behaviour of the Shannon entropy…

General Relativity and Quantum Cosmology · Physics 2015-06-05 J. Manuel Garcia-Islas

We investigate the meaning of gravity-induced decoherence in quantum theory, known as `intrinsic' or `fundamental' decoherence in the literature. We explore a range of issues relevant to this problem, including the meaning of modified…

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

Information spreads in time. For example, correlations dissipate when the correlated system locally couples to a third party, such as the environment. This simple but important fact forms the known quantum data-processing inequality. Here…

Quantum Physics · Physics 2024-03-15 Kun Zhang , Jin Wang

Quantum fluctuations or other moments of a state contribute to energy expectation values and can imply interesting physical effects. In quantum cosmology, they turn out to be important for a discussion of density bounds and instabilities of…

General Relativity and Quantum Cosmology · Physics 2014-07-02 Martin Bojowald