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The theoretical maximum time variation in the electronic charge permitted by the Generalized Second Law of Thermodynamics applied to black holes radiating and accreting in the cosmic microwave background matches the measured cosmological…

General Relativity and Quantum Cosmology · Physics 2010-04-02 Jane H. MacGibbon

The second law and the generalized second law of thermodynamics in cosmology in the framework of the modified Gauss-Bonnet theory of gravity are investigated. The conditions upon which these laws hold are derived and discussed.

General Relativity and Quantum Cosmology · Physics 2011-05-27 H. Mohseni Sadjadi

We investigate the fine-grained uncertainty relations for qubit system by measurements corresponding respectively to two and three spin operators. Then we derive the general bound for a combination of two probabilities of projective…

Quantum Physics · Physics 2021-09-24 Li-Hang Ren , Heng Fan

Here it is shown that the variation in the fine structure constant measured by Webb et al. matches the theoretically derived value for the maximum variation in the electronic charge permitted by the Generalized Second Law of Thermodynamics…

Astrophysics · Physics 2007-05-23 Jane H MacGibbon

In this essay, we discuss the fine-tuning problems of the Higgs mass and the cosmological constant. We argue that these are indeed legitimate problems, as opposed to some other "problems" that are sometimes described using similar…

High Energy Physics - Theory · Physics 2018-11-28 Yasha Neiman

In this paper, we investigate the validity of the generalized second law of thermodynamics of the universe bounded by the event horizon. Here we consider homogeneous and isotropic model of the universe filled with perfect fluid in one case…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Nairwita Mazumder , Subenoy Chakraborty

We discuss the Flambaum commentary [arXiv:0808.2518] on the application of the Generalized Second Law of Thermodynamics to derive limits on the variation of fundamental constants, for example the fine structure constant.

General Relativity and Quantum Cosmology · Physics 2009-02-27 Jane H MacGibbon

A classical and quantum mechanical generalized second law of thermodynamics in cosmology implies constraints on the effective equation of state of the universe in the form of energy conditions, obeyed by many known cosmological solutions,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Ram Brustein

A scheme for treating the Second Law of thermodynamics as a constraint and accounting for the approximate nature of constitutive assumptions in continuum thermomechanics is discussed. An unconstrained, concave, variational principle is…

Classical Physics · Physics 2024-12-31 Amit Acharya

We study the dynamical behavior of spinor particles, and get the energy-momentum relation of charged particles by solving the Dirac equation. Based on the energy-momentum relation, we investigate the laws of thermodynamics and the weak…

General Relativity and Quantum Cosmology · Physics 2019-03-22 Yi-Wen Han , Ming-Jian Lan , Xiao-Xiong Zeng

We relate the reported variation in the value of the fine structure constant to a possible non-universality of the gravitational interaction with respect to different particle generations.

High Energy Physics - Phenomenology · Physics 2007-05-23 Johann Rafelski

We make use of Dirac LNH and results for a time varying fine structure constant in order to derive possible laws of variation for speed of light, the number of nucleons in the Universe, energy density and gravitational constant. By…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

We investigate the validity of the generalized second law of thermodynamics in a universe governed by Horava-Lifshitz gravity. Under the equilibrium assumption, that is in the late-time cosmological regime, we calculate separately the…

High Energy Physics - Theory · Physics 2011-03-28 Mubasher Jamil , Emmanuel N. Saridakis , M. R. Setare

The generalized second law of thermodynamics for a system containing a black hole dynamical horizon is proposed in a covariant way. Its validity is also tested in case of adiabatically collapsing thick light shells.

General Relativity and Quantum Cosmology · Physics 2008-11-26 Song He , Hongbao Zhang

A violation of the distance-duality relation is directly linked with a temporal variation of the electromagnetic fine-structure constant. We consider a number of well-studied $f(T)$ gravity models and we revise the theoretical prediction of…

Cosmology and Nongalactic Astrophysics · Physics 2020-12-09 Jackson Levi Said , Jurgen Mifsud , David Parkinson , Emmanuel N. Saridakis , Joseph Sultana , Kristian Zarb Adami

After studying the energy-momentum relation of charged particles' Hamilton-Jacobi equations, we discuss the laws of thermodynamics and the weak cosmic censorship conjecture in torus-like black holes. We find that both the first law of…

High Energy Physics - Theory · Physics 2019-05-01 Yi-Wen Han , Xiao-Xiong Zeng , Yun Hong

Recent astrophysical observations suggest that the value of fine structure constant $\alpha=e^2/\hbar c$ may be slowly increasing with time. This may be due to an increase of $e$ or a decrease of $c$, or both. In this article, we argue from…

High Energy Physics - Theory · Physics 2014-11-18 Saurya Das , Gabor Kunstatter

An interesting question to explore in physics classes is whether gravity violates the second law of thermodynamics. Standard physics textbooks provide little to no discussion of the relationship between entropy and gravity, and the same is…

General Physics · Physics 2026-05-19 Jorge Pinochet , Giorgio Sonnino

Electromagnetic and gravitational central-field problems are studied with relativistic quantum mechanics on curved space-time backgrounds. Corrections to the transition current are identified. Analogies of the gravitational and…

General Physics · Physics 2015-02-04 U. D. Jentschura , J. H. Noble , I. Nandori

In black hole physics, the second law of thermodynamics is generally valid whether the black hole is a static or a non-static one. Considering the universe as a thermodynamical system the second law of black hole dynamics extends to the…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Subenoy Chakraborty , Nairwita Mazumder , Ritabrata Biswas
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