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Worldline quantum inequalities provide lower bounds on weighted averages of the renormalised energy density of a quantum field along the worldline of an observer. In the context of real, linear scalar field theory on an arbitrary globally…

General Relativity and Quantum Cosmology · Physics 2009-10-31 C. J. Fewster

The energy density of a conformally invariant scalar field around a cosmic string is estimated by the WKB method. This approach reproduces the precise value obtained by the other authors using the exact mode-sum method or the method of…

General Relativity and Quantum Cosmology · Physics 2020-07-02 Kiyoshi Shiraishi

We add a new scalar field in the no-scale Brans-Dicke gravity and require it to have a global O(2) symmetry with the original scalar field in the Brans-Dicke gravity. This gives us a new massless scalar field in the Einstein frame due to…

High Energy Physics - Phenomenology · Physics 2025-10-31 Muzi Hong , Kyohei Mukaida , Tsutomu T. Yanagida

In the work's considered density of vacuum energy and dynamic of scalar field in multidimensional theory with cosmological constant. Using method of N.N.Bogolubov coefficients, was gotten expression for influence of anisotropic metric to…

General Physics · Physics 2012-03-05 Sergey Yakovlev

The quantized Dirac field is known, by a result of Fewster and Verch, to satisfy a Quantum Weak Energy Inequality (QWEI) on its averaged energy density along time-like curves in arbitrary four-dimensional globally hyperbolic spacetimes.…

General Relativity and Quantum Cosmology · Physics 2009-11-11 S P Dawson , C J Fewster

We use the Allen et al. (2004) Chandra measurements of x-ray gas mass fraction of 26 rich clusters to place constraints on the scalar-field dark energy model with inverse power law potential energy density. The constraints are consistent…

Astrophysics · Physics 2009-11-10 Gang Chen , Bharat Ratra

We begin a systematic study of Quantum Energy Inequalities (QEIs) in relation to local covariance. We define notions of locally covariant QEIs of both 'absolute' and 'difference' types and show that existing QEIs satisfy these conditions.…

Mathematical Physics · Physics 2015-06-26 Christopher J. Fewster , Michael J. Pfenning

In N=1 supergravity supersymmetric (SUSY) and non-supersymmetric Minkowski vacua originating in the hidden sector can be degenerate. In the supersymmetric phase in flat Minkowski space non-perturbative supersymmetry breakdown may take place…

High Energy Physics - Phenomenology · Physics 2015-05-27 C. Froggatt , R. Nevzorov , H. B. Nielsen

Positivity bounds - constraints on any low-energy effective field theory imposed by the fundamental axioms of unitarity, causality and locality in the UV - have recently been used to constrain scalar-tensor theories of dark energy. However,…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-08 Claudia de Rham , Scott Melville , Johannes Noller

In the presence of the gravitational field, the energy density of matter no longer coincides with its mass density. A discrepancy exists, of course, also between the associated power spectra. Within the $\Lambda$CDM model, we derive a…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Maxim Eingorn , Ezgi Yilmaz , A. Emrah Yükselci , Alexander Zhuk

The possibility that the energy density of the Universe is dominated by a network of low-tension domain walls provides an alternative to the commonly discussed cosmological constant and scalar-field quintessence models of dark energy. We…

Astrophysics · Physics 2009-09-29 Alexander Friedland , Hitoshi Murayama , Maxim Perelstein

The self-gravitational correction to a localized spherically-symmetric static energy distribution is obtained from energetically self-consistent upgraded Newtonian gravitational theory. The result is a gravitational redshift factor that is…

General Physics · Physics 2014-01-28 Steven Kenneth Kauffmann

In this article, we estimate the quasi-local energy with reference to the Minkowski spacetime [16,17], the anti-de Sitter spacetime [4], or the Schwarzschild spacetime [3]. In each case, the reference spacetime admits a conformal…

Differential Geometry · Mathematics 2019-03-27 Po-Ning Chen , Mu-Tao Wang , Shing-Tung Yau

It is argued that the zero-point energies of free quantum fields diverge at most quadratically and not quartically, as is generally believed. This is a consequence of the relativistic invariance which requires that the energy density of the…

High Energy Physics - Theory · Physics 2007-05-23 E. Kh. Akhmedov

The original Casimir effect results from the difference in the vacuum energies of the electromagnetic field, between that in a region of space with boundary conditions and that in the same region without boundary conditions. In this paper…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Daniel Muller , Helio V. Fagundes

Quantum energy inequalities (QEIs) are state-independent lower bounds on weighted averages of the stress-energy tensor, and have been established for several free quantum field models. We present rigorous QEI bounds for a class of…

Mathematical Physics · Physics 2009-11-10 Christopher J. Fewster , Stefan Hollands

It is shown that a simple model for 4-dimensional quantum gravity based on a 3-dimensional generalization of anyon superconductivity can be regarded as a discrete form of Polyakov's string theory. This suggests that there is a universal…

High Energy Physics - Theory · Physics 2009-10-31 George Chapline

In this letter we address some of the issues raised in the literature about the conflict between a large vacuum energy density, apriori predicted by quantum field theory, and the observed dark energy which must be the energy of vacuum or…

High Energy Physics - Theory · Physics 2012-08-08 Houri Ziaeepour

An upper limit to non-Newtonian attracive forces is obtained from the measurement of quantum states of neutrons in the Earth's gravitational field. This limit improves the existing constrains in the nanometer range.

High Energy Physics - Phenomenology · Physics 2009-11-10 V. V. Nesvizhevsky , K. V. Protasov

We present a study of energy density and pressure of a free real scalar quantum field after its decoupling from a thermal bath in the spatially flat Friedman-Lema\^itre-Robertson-Walker space-time by solving the Klein-Gordon equation both…

General Relativity and Quantum Cosmology · Physics 2025-04-15 F. Becattini , D. Roselli