English
Related papers

Related papers: Bouncing universe in a heat bath

200 papers

We examine the cosmological implications of space-time non-commutativity, discovering yet another realization of the varying speed of light model. Our starting point is the well-known fact that non-commutativity leads to deformed dispersion…

High Energy Physics - Theory · Physics 2010-01-06 Stephon H. S. Alexander , João Magueijo

The evolution of the luminosity distance in a contracting universe is studied. It is shown that for quite a lot of natural dynamical evolutions, its behavior is far from trivial and its value can even decrease with an increasing time…

General Relativity and Quantum Cosmology · Physics 2017-12-27 Aurélien Barrau , Killian Martineau , Flora Moulin

Recently, we have generalized the Bekenstein-Hawking entropy formula for black holes embedded in expanding Friedmann universes. In this letter, we begin the study of this new formula to obtain the first law of thermodynamics for dynamical…

High Energy Physics - Theory · Physics 2015-08-11 Stefano Viaggiu

The positivity conditions of the relative entropy between two thermal equilibrium states $\hat{\rho}_1$ and $\hat{\rho}_2$ are used to obtain upper and lower bounds for the subtraction of their entropies, the Helmholtz potential and the…

The second law of thermodynamics places a limitation into which states a system can evolve into. For systems in contact with a heat bath, it can be combined with the law of energy conservation, and it says that a system can only evolve into…

Quantum Physics · Physics 2015-11-20 Piotr Ćwikliński , Michał Studziński , Michał Horodecki , Jonathan Oppenheim

We study thermal radiation outside equilibrium. The situation considered consists of two bodies emitting photons at two different temperatures. We show that the system evolves to a stationary state characterized by an energy current which…

Statistical Mechanics · Physics 2017-02-01 Agustin Perez-Madrid , J. Miguel Rubi , Luciano C. Lapas

We have shown the thermodynamic changes in a 2+1-dimensional rotating black hole when it absorbs a particle. The microscopic changes which the black hole undergoes are interpreted using the AdS/CFT correspondence. Using particle absorption…

General Relativity and Quantum Cosmology · Physics 2017-12-01 Bogeun Gwak , Bum-Hoon Lee

The Brownian motion of a quantum particle in a harmonic confining potential and coupled to a harmonic quantum thermal bath is exactly solvable. It is shown that at low enough temperatures the stationary state is non-Gibbsian due to an…

Statistical Mechanics · Physics 2007-05-23 Th. M. Nieuwenhuizen , A. E. Allahverdyan

The relativistic continuity equations for the extensive thermodynamic quantities are derived based on the divergence theorem in Minkowski space outlined by St\"uckelberg. This covariant approach leads to a relativistic formulation of the…

Statistical Mechanics · Physics 2022-10-11 Sylvain D. Brechet , Marin C. A. Girard

We take the view that the standard von Neumann definition, in which the entropy $S^{vN}$ of a pure state is zero, is in evident conflict with the statement of the second law that the entropy of the universe $S_{univ}$ increases in…

Quantum Physics · Physics 2018-10-25 George L. Barnes , Phillip C. Lotshaw , Michael E. Kellman

A bouncing cosmology with an initial matter-dominated phase of contraction during which scales which are currently probed with cosmological observations exit the Hubble radius provides a mechanism alternative to inflation for producing a…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-20 Robert H. Brandenberger

Using the generalized procedure proposed by \emph{Wu et al}\cite{wu} recently, we construct the first law of thermodynamics on apparent horizon in a general braneworld model with curvature correction terms on the brane and in the bulk,…

General Relativity and Quantum Cosmology · Physics 2010-01-07 Tao Zhu , Ji-Rong Ren , Shu-Fan Mo

Starting from the first law of thermodynamics, $dE=T_hdS_h+WdV$, at apparent horizon of a FRW universe, and assuming that the associated entropy with apparent horizon has a quantum corrected relation, $S=\frac{A}{4G}-\alpha \ln…

High Energy Physics - Theory · Physics 2011-02-09 Ahmad Sheykhi

The de Sitter thermodynamics of cosmological models with a modified Friedmann equation is considered, with particular reference to high-energy Randall-Sundrum and Gauss-Bonnet braneworlds. The Friedmann equation can be regarded as the first…

High Energy Physics - Theory · Physics 2009-11-11 Gianluca Calcagni

Using the first law of thermodynamics, we propose a relation between the system entropy ($S$) and its IR ($L$) and UV ($\Lambda$) cutoffs. In addition, applying this relation to the apparent horizon of flat FRW universe, whose entropy meets…

General Physics · Physics 2018-10-18 H. Moradpour , S. A. Moosavi , I. P. Lobo , J. P. Morais Graça , A. Jawad , I. G. Salako

The Bekenstein-Hawking entropy suggests that thermodynamics is an intrinsic ingredient of gravity. Here, we explore the idea that requirements of thermodynamic consistency could determine the gravitational entropy in other set-ups. We…

General Relativity and Quantum Cosmology · Physics 2011-12-23 Charis Anastopoulos , Ntina Savvidou

In this paper, the generalized second law (GSL) of thermodynamics and entropy is revisited in the context of cosmological models with bouncing behavior such as chameleon cosmology where the boundary of the universe is assumed to be enclosed…

General Relativity and Quantum Cosmology · Physics 2015-05-28 H. Farajollahi , A. Salehi , F. Tayebi

A study of Universal thermodynamics is done in the frame work of RSII brane model and DGP brane scenario. The Universe is chosen as FRW model bounded by apparent or event horizon. Assuming extended Hawking temperature on the horizon, the…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Saugata Mitra , Subhajit Saha , Subenoy Chakraborty

A theoretical study of small thermal and electromagnetic perturbations in type-II superconductors is studied in the flux creep regime with a power-law voltage-current characteristics. The space-time evolution of temperature and electric…

Superconductivity · Physics 2015-03-13 N. A. Taylanov , A. S. Rakhmatov

We investigate an asymptotically spatially flat Robertson-Walker spacetime from two different perspectives. First, using von Neumann entropy, we evaluate the entanglement generation due to the encoded information in spacetime. Then, we work…

Quantum Physics · Physics 2017-06-21 Mehrnoosh Farahmand , Hosein Mohammadzadeh , Hossein Mehri-Dehnavi
‹ Prev 1 8 9 10 Next ›