Related papers: Does the generalized second law require entropy bo…
We have investigated the thermodynamical properties of dark energy. Assuming that the dark energy temperature $T\sim a^{-n}$ and considering that the volume of the Universe enveloped by the apparent horizon relates to the temperature, we…
The present study is motivated by the study of reference [1], where the generalized second law of thermodynamics has been investigated for a flat FRW universe for two viable models of $f(T)$ gravity. In the present work, we have considered…
Several results of black holes thermodynamics can be considered as firmly founded and formulated in a very general manner. From this starting point we analyse in which way these results may give us the opportunity to gain a better…
We examine the second law of thermodynamics in the context of horizon cosmology, in particular, whether the change of total entropy (i.e. the sum of the entropy for the apparent horizon and the entropy for the matter fields) proves to be…
We show that the collapse of the entangled quantum state makes the entropy increase in an isolated system. The second law of thermodynamics is thus proven in its most general form.
Second law of thermodynamics imposes that in any thermodynamic process the entropy production must be nonnegative. In continuum physics such a requirement is fulfilled by postulating the constitutive equations which represent the material…
Zaslavskii has suggested how to tighten Bekenstein's bound on entropy when the object is electrically charged. Recently Hod has provided a second tighter version of the bound applicable when the object is rotating. Here we derive…
We consider a spatially flat Friedmann-Lemaitre-Robertson-Walker space time and investigate the second law and the generalized second law of thermodynamics for apparent horizon in generalized modified Gauss Bonnet theory of gravity (whose…
We study the relation between the thermodynamics and field equations of generalized gravity theories on the dynamical trapping horizon with sphere symmetry. We assume the entropy of dynamical horizon as the Noether charge associated with…
The accretion of a phantom fluid with non-zero chemical potential by black holes is discussed with basis on the Generalized Second Law of thermodynamics. For phantom fluids with positive temperature and negative chemical potential we…
We examine the validity of the generalized second law (GSL) of gravitational thermodynamics in the context of interacting $f(R)$ gravity. We take into account that the boundary of the universe to be confined by the dynamical apparent…
We look at a gas of dust and investigate how its entropy evolves with time under a spherically symmetric gravitational collapse. We treat the problem perturbatively and find that the classical thermodynamic entropy does actually increase to…
We derive again the upper entropy bound for a charged object by employing thermodynamics of the Kerr-Newman black hole linearised with respect to its electric charge
The first law of black hole thermodynamics is suitable for any diffeomorphism invariant gravity, and the entropy in the first law is the Wald entropy which is highly dependent on the non-minimal coupling interactions in the theory of…
There would be a perfect correspondence between the laws of classical thermodynamics and black hole thermodynamics, except for the apparent failure of black hole thermodynamics to correspond to the Third Law. The classical Third Law of…
In a classical spacetime satisfying Einstein's equation and the null convergence condition, the same quantum mechanical effects that cause black holes to have a temperature are found to imply, if joined to the macroscopic nature of entropy,…
We explore the impact of the Generalized Uncertainty Principle (GUP) on the thermodynamics of five-dimensional Einstein-Gauss-Bonnet (EGB) black holes. A modified mass-temperature relation is derived under the assumption of local…
Experimental and theoretical results about entropy limits for macroscopic and single-particle systems are reviewed. It is clarified when it is possible to speak about a quantum of entropy, given by the Boltzmann constant k, and about a…
We discuss the generalized second law (GSL) and the constraints imposed by it for two types of Friedmann universes. The first one is the Friedmann universe with radiation and a positive cosmological constant, and the second one consists of…
We prove a generalization of the classic Groenewold-Lindblad entropy inequality, combining decoherence and the quantum Bayes theorem into a simple unified picture where decoherence increases entropy while observation decreases it. This…