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Related papers: Fluctuation energies in quantum cosmology

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In loop quantum cosmology, the values of volume fluctuations and correlations determine whether the dynamics of an evolving state exhibits a bounce. Of particular interest are states that are supported only on either the positive or the…

General Relativity and Quantum Cosmology · Physics 2020-01-06 Martin Bojowald

We show that due to entanglement, quantum fluctuations may differ significantly from statistical fluctuations. We calculate quantum fluctuations of the particle number and of the energy in a sub-volume of a system of bosons in a pure state,…

High Energy Physics - Theory · Physics 2008-11-26 Ram Brustein , Amos Yarom

A formula to calculate the quantum fluctuations of energy in small subsystems of a hot and relativistic gas is derived. We find an increase in fluctuations for subsystems of small sizes, but we agrees with the energy fluctuations in the…

Nuclear Theory · Physics 2021-10-08 Rajeev Singh

The quantum fluctuations of a physical property can be observed in the measurement statistics of any measurement that is at least partially sensitive to that physical property. Quantum theory indicates that the effective distribution of…

Quantum Physics · Physics 2020-12-25 Holger F. Hofmann

It is suggested that the vacuum expectation of the quantum vacuum energy-momentum is zero, but quantum fluctuations give rise to a space-time curvature equivalent to that of a cosmological constant or dark energy. Calculations within…

General Relativity and Quantum Cosmology · Physics 2009-02-26 Emilio Santos

We derive a formula that defines quantum fluctuations of energy in subsystems of a hot relativistic gas. For small subsystem sizes we find substantial increase of fluctuations compared to those known from standard thermodynamic…

High Energy Physics - Phenomenology · Physics 2021-12-15 Arpan Das , Wojciech Florkowski , Radoslaw Ryblewski , Rajeev Singh

We discuss the role of quantum coherence in the energy fluctuations of open quantum systems. To this aim, we introduce a protocol, to which we refer to as the end-point-measurement scheme, allowing to define the statistics of energy changes…

Quantum Physics · Physics 2022-04-13 S. Gherardini , A. Belenchia , M. Paternostro , A. Trombettoni

Quantum gravitational effects may induce stochastic fluctuations in the structure of space-time, to produce a characteristic foamy structure. It has been known for some time now that these fluctuations may have observable consequencies for…

Astrophysics · Physics 2011-04-05 R. Aloisio , P. Blasi , A. Galante , A. F. Grillo

Expressions for the quantum fluctuations of energy density have been derived for the subsystems consisting of hot relativistic gas of particles with spin-$\frac{1}{2}$ and mass $m$. Our expressions for the fluctuation depend on the form of…

Quantum Physics · Physics 2021-11-10 Rajeev Singh

We introduce and review briefly the phenomenon of quantum annealing and analog computation. The role of quantum fluctuation (tunneling) in random systems with rugged (free) energy landscapes having macroscopic barriers are discussed to…

Statistical Mechanics · Physics 2023-10-16 Bikas K Chakrabarti , Sudip Mukherjee

In the process of work it has been found that space-time quantum fluctuations are naturally described in terms of the deformation parameter introduced on going from the well-known quantum mechanics to that at Planck scales and put forward…

General Physics · Physics 2013-06-13 A. E. Shalyt-Margolin

We derive the fluctuation theorem for quantum-state statistics that can be obtained when we initially measure the total energy of a quantum system at thermal equilibrium, let the system evolve unitarily, and record the quantum-state data…

Statistical Mechanics · Physics 2018-08-01 Naoto Tsuji , Masahito Ueda

We argue that it is a fluctuational underpinning of the Quantum vacuum which on the one hand gives a stochastic character to the conservation laws, and on the other is required for explaining the recently observed acceleration of the…

General Physics · Physics 2015-06-26 B. G. Sidharth

We investigate an influence of virtual particles on the classical motion of a system in Minkowski and Euclidean spaces. Our results indicate that fluctuations of fields different from the main field decelerate significantly its motion at…

High Energy Physics - Phenomenology · Physics 2016-08-16 S. G. Rubin , H. Kröger , G. Melkonian

It is generally expected that quantum gravity affects the structure of space-time by introducing stochastic fluctuations in the geometry, and, ultimately, in the measurements of four-distances and four-momenta.These fluctuations may induce…

Astrophysics · Physics 2007-05-23 R. Aloisio , P. Blasi , A. Galante , P. L. Ghia , A. F. Grillo

We discuss the role of quantum coherence in the energy fluctuations of open quantum systems. To this aim, we introduce an operational protocol, to which we refer to as the end-point-measurement scheme, allowing to define the statistics of…

Quantum Physics · Physics 2021-11-23 S. Gherardini , A. Belenchia , M. Paternostro , A. Trombettoni

Phase fluctuations determine the low-energy properties of quantum condensates. However, at the condensation threshold, both density and phase fluctuations are relevant. While strong emphasis has been given to the investigation of phase…

Quantum gravitational effects may induce stochastic fluctuations in the structure of space-time, to produce a characteristic foamy structure. It has been known for some time now that these fluctuations may have observable consequences for…

General Relativity and Quantum Cosmology · Physics 2016-11-09 R. Aloisio , P. Blasi , A. Galante , A. F. Grillo

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

We study quantum measurements of temporal equilibrium fluctuations in macroscopic quantum systems. It is shown that the fluctuation-dissipation theorem, as a relation between observed quantities, is partially violated in quantum systems,…

Statistical Mechanics · Physics 2017-02-13 Akira Shimizu , Kyota Fujikura
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