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Related papers: Semiclassical relativistic stars

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A semiclassical approximation is derived by using a family of wavepackets to map arbitrary wavefunctions into phase space. If the Hamiltonian can be approximated as linear over each individual wavepacket, as often done when presenting…

Quantum Physics · Physics 2024-04-30 Clay D. Spence

In the framework of Teleparallel Gravity, we derive a charged non-vacuum solution for a physically symmetric tetrad field with two unknown functions of radial coordinate. The field equations result in a closed-form adopting particular…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Gamal G. L. Nashed , Salvatore Capozziello

Bifurcations of classical orbits introduce divergences into semiclassical spectra which have to be smoothed with the help of uniform approximations. We develop a technique to extract individual energy levels from semiclassical spectra…

Chaotic Dynamics · Physics 2009-11-07 T. Bartsch , J. Main , G. Wunner

In this research, we explore the semiclassical approximation to canonical quantum gravity and how a classical background emerges from the Wheeler-DeWitt (WDW) states. By employing the Wigner functional analysis, we derive the backreacted…

General Relativity and Quantum Cosmology · Physics 2023-09-18 Rifath Khan

We study spherically symmetric static spacetimes generally filled with an anisotropic fluid in the nonrelativistic general covariant theory of gravity. In particular, we find that the vacuum solutions are not unique, and can be expressed in…

High Energy Physics - Theory · Physics 2011-01-27 Jared Greenwald , V. H. Satheeshkumar , Anzhong Wang

The semiclassical Einstein equations are solved to first order in $\epsilon = \hbar/M^2$ for the case of an extreme or nearly extreme Reissner-Nordstr\"{o}m black hole perturbed by the vacuum stress-energy of quantized free fields. It is…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Paul R. Anderson , William A. Hiscock , Brett E. Taylor

Linear cosmological perturbations of a large class of modified gravity and dark energy models can be unified in the effective field theory of cosmic acceleration, encompassing Horndeski scalar-tensor theories and beyond. The fully available…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-25 Lucas Lombriser , Andy Taylor

In 1953 Casimir proposed a semiclassical model for the electron based on the concept that net inward radiation pressure from the electromagnetic vacuum fluctuations fields (as in the Casimir effect, generally) might play the role of…

General Physics · Physics 2008-11-26 H. E. Puthoff

It has been shown that gravitational fields produced by realistic classical-matter distributions can force quantum vacuum fluctuations of some nonminimally coupled free scalar fields to undergo a phase of exponential growth. The…

General Relativity and Quantum Cosmology · Physics 2015-01-09 André G. S. Landulfo , William C. C. Lima , George E. A. Matsas , Daniel A. T. Vanzella

In the mathematically rigorous analysis of semiclassical Einstein's equations, the renormalisation of the stress-energy tensor plays a crucial role. We address such a topic in the case of a scalar field with both arbitrary mass and coupling…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Claudio Dappiaggi , Klaus Fredenhagen , Nicola Pinamonti

In this article, we provide a pedagogical review of the Tolman-Oppenheimer-Volkoff (TOV) equation and its solutions which describe static, spherically symmetric gaseous stars in general relativity. Our discussion starts with a systematic…

General Relativity and Quantum Cosmology · Physics 2021-06-15 Emmanuel Chavez Nambo , Olivier Sarbach

The field equations of a special class of tetrad theory of gravitation have been applied to tetrad space having three unknown functions of radial coordinate. The spherically symmetric vacuum stress-energy momentum tensor with one assumption…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Gamal G. L. Nashed

We address the existence of globally neutral neutron star configurations in contrast with the traditional ones constructed by imposing local neutrality. The equilibrium equations describing this system are the Einstein-Maxwell equations…

Solar and Stellar Astrophysics · Physics 2009-11-25 Jorge A. Rueda , Remo Ruffini , She-Sheng Xue

We obtain renormalized stress tensor of a mass-less, charge-less dynamical quantum scalar field, minimally coupled with a spherically symmetric static Lukewarm black hole. In two dimensional analog the minimal coupling reduces to the…

General Physics · Physics 2013-05-30 H. Ghaffarnejad , H. Neyad , M. A. Mojahedi

We complete our previous investigation concerning the structure and the stability of "isothermal" spheres in general relativity. This concerns objects that are described by a linear equation of state $P=q\epsilon$ so that the pressure is…

Astrophysics · Physics 2009-11-13 Pierre-Henri Chavanis

In this study, we present a generalized spherically symmetric, anisotropic and static compact stellar model in $f(T)$ gravity, where $T$ represents the torsion scalar. By employing the Karmarkar condition we have obtained embedding class 1…

General Relativity and Quantum Cosmology · Physics 2018-11-30 Debabrata Deb , Shounak Ghosh , S. K. Maurya , Maxim Khlopov , Saibal Ray

We consider the quasi-classical model of the spin-free configuration on the basis of the self-gravitating spherical dust shell in General Relativity. For determination of the energy spectrum of the stationary states on the basis of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 V. D. Gladush

Einstein originally proposed a nonsymmetric tensor field, with its symmetric part associated with the spacetime metric and its antisymmetric part associated with the electromagnetic field, as an approach to a unified field theory. Here we…

General Relativity and Quantum Cosmology · Physics 2018-03-14 J. R. van Meter

We construct models of triaxial galactic nuclei containing central black holes using the method of orbital superposition, then verify their stability by advancing N-body realizations of the models forward in time. We assume a power-law form…

Astrophysics · Physics 2009-11-07 M. Y. Poon , D. Merritt

Quantum fields do not satisfy the pointwise energy conditions that are assumed in the original singularity theorems of Penrose and Hawking. Accordingly, semiclassical quantum gravity lies outside their scope. Although a number of…

General Relativity and Quantum Cosmology · Physics 2022-04-13 Christopher J. Fewster , Eleni-Alexandra Kontou