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Related papers: Stellar equilibrium on a physical vacuum soil

200 papers

We investigate the effects of quantum backreaction on the Schwarzschild geometry in the semiclassical approximation. The renormalized stress-energy tensor (RSET) of a scalar field is modelled via an order reduction of the analytical…

General Relativity and Quantum Cosmology · Physics 2023-07-26 Julio Arrechea , Carlos Barceló , Raúl Carballo-Rubio , Luis J. Garay

This investigation delves into the ringdown signals produced by semiclassical stars, which are ultra-compact, regular solutions of the Einstein equations incorporating stress-energy contributions from quantum vacuum polarization. These…

General Relativity and Quantum Cosmology · Physics 2024-12-04 Julio Arrechea , Stefano Liberati , Vania Vellucci

It is assumed that, for weak spacetime curvature, the main gravitational effect of the quantum vacuum stress-energy corresponds to adding two terms to the Einstein-Hilbert action, proportional to the square of the curvature scalar and to…

General Relativity and Quantum Cosmology · Physics 2010-04-23 Emilio Santos

Relativistic effects of compact objects onto electromagnetic fields in their vicinity are investigated using the test-field approximation. In particular, we study the possible emergence of magnetic null points which are astrophysically…

High Energy Astrophysical Phenomena · Physics 2019-02-27 Ondřej Kopáček , Tayebeh Tahamtan , Vladimír Karas

Classical energy conditions are investigated in generic static and spherically symmetric spacetimes. In setups with nonconstant $g_{tt} g_{rr}$, the appearance of horizons can signal the violation of the null energy condition and the…

General Relativity and Quantum Cosmology · Physics 2026-04-30 Zi-Liang Wang , Emmanuele Battista

We provide an exhaustive analysis of the complete set of solutions of the equations of stellar equilibrium under semiclassical effects. As classical matter we use a perfect fluid of constant density; as the semiclassical source we use the…

General Relativity and Quantum Cosmology · Physics 2021-10-22 Julio Arrechea , Carlos Barceló , Raúl Carballo-Rubio , Luis J. Garay

An alternative cosmological model is presented, which avoids the requirement of dark energy and dark matter. Based on the proposition that energy conservation should be valid not only locally but also globally, the energy tensor of general…

General Physics · Physics 2007-08-30 Ernst Fischer

This paper explores the theoretical implications of quantum gravity by analyzing compact stellar objects, presenting three distinct models that serve as alternatives to traditional black holes. These models are characterized by their…

General Relativity and Quantum Cosmology · Physics 2025-12-02 Salvatore Samuele Sirletti , Piero Nicolini , Mariafelicia De Laurentis

We have recently proposed a model for a regular black hole, or an ultra-compact object, that is premised on having maximally negative radial pressure throughout the entirety of the object's interior. This model can be viewed as that of a…

General Relativity and Quantum Cosmology · Physics 2022-01-19 Ram Brustein , A. J. M. Medved , Tamar Simhon

Regular black holes have become a popular alternative to the singular mathematical black holes predicted by general relativity as they circumvent mathematical pathologies associated with the singularity while preserving crucial black hole…

General Relativity and Quantum Cosmology · Physics 2024-08-15 Ioannis Soranidis

We consider the backreaction problem of a quantized minimally coupled massless scalar field in cosmology. The adiabatically regularized stress-energy tensor in a general Friedmann-Robertson-Walker background is approximately evaluated by…

General Relativity and Quantum Cosmology · Physics 2013-06-04 Ali Kaya , Merve Tarman

We obtain well behaved interior solutions describing hydrostatic equilibrium of anisotropic relativistic stars in scale-dependent gravity, where Newton's constant is allowed to vary with the radial coordinate throughout the star. Assuming…

General Relativity and Quantum Cosmology · Physics 2021-01-26 Grigoris Panotopoulos , Angel Rincon , Ilidio Lopes

We present new static spherically-symmetric exact solutions of Einstein equations with the quintessential matter surrounding a black hole charged or not as well as for the case without the black hole. A condition of additivity and linearity…

General Relativity and Quantum Cosmology · Physics 2010-11-19 V. V. Kiselev

We present new sequences of general relativistic, quasiequilibrium black hole-neutron star binaries. We solve for the gravitational field in the conformal thin-sandwich decomposition of Einstein's field equations, coupled to the equations…

Astrophysics · Physics 2009-11-11 Keisuke Taniguchi , Thomas W. Baumgarte , Joshua A. Faber , Stuart L. Shapiro

Kerr-Schild solutions to the vacuum Einstein equations are considered from the viewpoint of integral equations. We show that, for a class of Kerr-Schild fields, the stress-energy tensor can be regarded as a total divergence in Minkowski…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Chris Doran , Anthony Lasenby

We consider a massive scalar field living on the recently found exact quantum space-time corresponding to vacuum spherically symmetric loop quantum gravity. The discreteness of the quantum space time naturally regularizes the scalar field,…

General Relativity and Quantum Cosmology · Physics 2015-12-16 Nahuel Barrios , Rodolfo Gambini , Jorge Pullin

We study the backreaction of free quantum fields on a flat Robertson-Walker spacetime. Apart from renormalization freedom, the vacuum energy receives contributions from both the trace anomaly and the thermal nature of the quantum state. The…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-29 Claudio Dappiaggi , Thomas-Paul Hack , Jan Möller , Nicola Pinamonti

We study the renormalized stress-energy tensor (RSET) for static quantum states on (n+1)-dimensional, static, spherically symmetric black holes. By solving the conservation equations, we are able to write the stress-energy tensor in terms…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Dean Morgan , Stuart Thom , Elizabeth Winstanley , Phil M. Young

Analytic approximations for the stress-energy of quantized fields in the Hartle-Hawking state in static black hole spacetimes predict divergences on the event horizon of the black hole for a number of important cases. Such divergences, if…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Paul R. Anderson , Mathew Binkley , Hector Calderon , William A. Hiscock , Emil Mottola , Ruslan Vaulin

Alternative forms of the solutions to the quantum field equations and their implications for physical theory are considered. Incorporation of these alternative solution forms, herein deemed "supplemental solutions", into the development of…

General Physics · Physics 2019-03-05 Robert D. Klauber