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In a recent trilogy we proposed a Statistical Theory of General Relativity spacetime. Here we apply our new theory to determine the (energy) ``density'' and (virial) ``temperature'' dependence of the structure of the spacetime quantum…

General Physics · Physics 2025-10-21 Riccardo Fantoni

It has been built a strict mathematical model of the thermodynamic equilibrium's establishment in the originally nonequilibrium cosmological ultrarelativistic plasma for the arbitrary accelerated Universe under the assumption that scaling…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Yurii Ignatyev

It is argued that the world is a dissipative dynamic system, a phase flow of which is formed by conformally-symplectic mapping. The key assumption is that the concept of energy in microcosm makes sense only for the steady motions…

Dynamical Systems · Mathematics 2009-04-08 A. P. Alexandrov

In this work, we study cosmological spacetime configurations in $f(Q)$ gravity with nonvanishing symmetric teleparallel connections. It is known that the spatially flat, homogeneous and isotropic connections can be classified into three…

General Relativity and Quantum Cosmology · Physics 2025-01-30 María-José Guzmán , Laur Järv , Laxmipriya Pati

An equilibrium statistical system is known to be stable if the fluctuations of global observables are normal, when their dispersions are proportional to the number of particles, or to the system volume. A general theorem is rigorously…

Statistical Mechanics · Physics 2009-11-11 V. I. Yukalov

The initial singularity problem in standard general relativity is treated on the light of a viewpoint asserting that this formulation of Einstein's theory and its conformal formulations are physically equivalent. We show that flat…

General Relativity and Quantum Cosmology · Physics 2012-10-30 Israel Quiros

We explore static spherically symmetric stars in the Gauss-Bonnet gravity without cosmological constant, and present an exact internal solution which attaches to the exterior vacuum solution outside stars. It turns out that the presence of…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Kang Zhou , Zhan-Ying Yang , De-Cheng Zou , Rui-Hong Yue

In this paper, we present a "stellar dynamics" model of an infinite Universe, where matter distribution follows an inverse proportionality squared relationship with respect to the distance from the rotation center of galaxy clusters and…

General Physics · Physics 2025-07-10 E. Lopez Sandoval

Einstein--Cartan theory is a generalization of general relativity that introduces spacetime torsion. In this paper, we perform phase space analysis to investigate the evolution of the early universe in Einstein--Cartan theory. By studying…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Qihong Huang , He Huang , Bing Xu , Kaituo Zhang

We formulate within a generalized distributional approach the treatment of the stability against radial perturbations for both neutral and charged stratified stars in Newtonian and Einstein's gravity. We obtain from this approach the…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Jonas P. Pereira , Jorge A. Rueda

Completely open systems can exchange heat, work, and matter with the environment. While energy, volume, and number of particles fluctuate under completely open conditions, the equilibrium states of the system, if they exist, can be…

Statistical Mechanics · Physics 2017-01-25 Ivan Latella , Agustín Pérez-Madrid , Alessandro Campa , Lapo Casetti , Stefano Ruffo

In terms of fundamental principles of quantum theory of interacting particles and relativistic kinetic theory there was carried out an analysis of the main principle of standard cosmological scenario - the initial existence of local…

General Relativity and Quantum Cosmology · Physics 2011-06-21 Yurii G. Ignatyev

We derive the equation for pressure within a neutron star, taking into account a non-zero cosmological constant ($\Lambda$). We then examine the stability of the neutron star's equilibrium state in the presence of cosmological constant. Our…

General Relativity and Quantum Cosmology · Physics 2025-04-22 Naveen K. Singh , Gopal Kashyap

The thermodynamic equilibrium condition for a static self-gravitating fluid in the Einstein theory is defined by the Tolman-Ehrenfest temperature law, $T{\sqrt {g_{00}(x^{i})}} = constant$, according to which the proper temperature depends…

General Relativity and Quantum Cosmology · Physics 2020-09-02 J. A. S. Lima , A. Del Popolo , A. R. Plastino

An extremely fast exponential expansion of the Universe is typical for the stable version of the inflationary model, based on the anomaly-induced action of gravity. The total amount of exponential $e$-folds could be very large, before the…

High Energy Physics - Theory · Physics 2021-08-05 Wagno Cesar e Silva , Ilya L. Shapiro

The regularized vacuum energy (or energy density) of a quantum field subjected to static external conditions is shown to satisfy a certain partial differential equation with respect to two variables, the mass and the "time" (ultraviolet…

Mathematical Physics · Physics 2009-11-11 S. A. Fulling

We study the statistical mechanics of the early radiation dominated universe in the context of a generalized uncertainty principle which supports the existence of a minimal length scale. Utilizing the resultant modified thermodynamical…

General Relativity and Quantum Cosmology · Physics 2016-01-22 B. Vakili , M. A. Gorji

By using the conserved currents in the bulk space-time, we study dynamical holographic systems and the relation between thermodynamical and dynamical stability of such systems. In particular, in the probe limit a generalized free energy is…

High Energy Physics - Theory · Physics 2023-10-09 Yu Tian , Xiao-Ning Wu , Hongbao Zhang

In the metric approach of $f(R)$ theories of gravity, the fourth-order field equations are often recast as effective Einstein equations in the presence of standard matter and a curvature fluid (which gathers all the extra terms), always in…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Juan M. Z. Pretel , Sergio E. Jorás , Ribamar R. R. Reis

We investigate the realization of the emergent universe scenario in theories with natural UV cutoffs, namely a minimum length and a maximum momentum, quantified by a new deformation parameter in the generalized uncertainty principle. We…

General Relativity and Quantum Cosmology · Physics 2017-12-07 Mohsen Khodadi , Kourosh Nozari , Emmanuel N. Saridakis
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