Related papers: Misner-Sharp Mass and the Unified First Law in Mas…
Generalized symmetries and their spontaneous breakdown serve as the fundamental concept to constrain the many-body entanglement structure, which allows us to characterize quantum phases of matter and emergent collective excitations. For…
In this letter, we try to apply the unified first law to the "cosmic triad" vector field scenario both in the minimal coupling case and in the non-minimalcoupling case. After transferring the non-minimally coupling action in Jordan frame to…
Gravitational waves in cylindrically symmetric Einstein gravity are described by an effective energy tensor with the same form as that of a massless Klein- Gordon field, in terms of a gravitational potential generalizing the Newtonian…
In three dimensions, we consider the Einstein-Maxwell Lagrangian dressed by a nonminimally coupled scalar field in New Massive Gravity. For this theory, we provide two families of electrically charged Lifshitz black holes where their metric…
Given that the dark matter and dark energy in the universe affect cosmological observables only gravitationally, their phenomenology may be described by a single stress energy tensor. True unification however requires a theory that…
A covariant formulation of a theory with a massive graviton and no negative energy state has been recently proposed as an alternative to the usual General Relativity framework. For a spatially flat homogenous and isotropic universe, the…
We consider the formulation of entropic gravity in two spacetime dimensions. The usual gravitational force law is derived even in the absence of area, as normally required by the holographic principle. A special feature of this perspective…
It is well known that a physical medium that sets a Lorentz frame generates a Lorentz-breaking gap for a graviton. We examine such generated "mass" terms in the presence of a fluid medium whose ground state spontaneously breaks spatial…
Here, we study the generalized second law (GSL) of thermodynamics in the framework of massive gravity. To do this, we consider a FRW universe filled only with matter and enclosed by the apparent horizon. In addition, we consider two models…
Recent work has established the existence of stable quantum phases of matter described by symmetric tensor gauge fields, which naturally couple to particles of restricted mobility, such as fractons. We focus on a minimal toy model of a rank…
The Arnowitt-Deser-Misner formalism is used to derive variations of mass, angular momentum and canonical energy for Einstein-Maxwell {\it dark matter} gravity in which the auxiliary gauge field coupled via kinetic mixing term to the…
The covariant canonical expression for the conserved charges, proposed by Nester, is tested on several solutions in 3D gravity with or without torsion and topologically massive gravity. In each of these cases, the calculated values of…
In a compressed Nuclear Matter (NM) an increasing pressure between the nucleons starts to increase the ratio of a nucleon Fermi to average single particle energy and in accordance with the Hugenholtz-van Hove theorem the longitudinal…
We study new classes of generic off-diagonal and diagonal cosmological solutions for effective Einstein equations in modified gravity theories, MGTs, with modified dispersion relations, MDRs, encoding possible violations of (local) Lorentz…
We study the problem of gravitational collapse in the context of scalar-tensor theories of Gravity. We introduce a new hydrodynamical formulation in the Einstein frame, inspired by that of Misner and Sharp. We obtain the equilibrium…
It is well-known that the mass of a non-asymptotically flat spacetime cannot be uniquely defined. Some mass formulas for the Kerr-AdS black hole have been found and used in studying black hole thermodynamics. However, the derivations…
In this work, we scrutinize the thermodynamic properties of the Simpson-Visser (SV) spacetime. Working within Einstein gravity coupled to nonlinear electrodynamics (NLED) and a scalar field with negative kinetic energy, we rederive the…
We introduce in this document a direct method allowing to solve numerically inverse type problems for linear parabolic equations. We consider the reconstruction of the full solution of the parabolic equation posed in $\Omega\times (0,T)$ -…
The theories known as doubly special relativity are introduced in order to take into account an observer-independent length scale and the speed of light in the framework of special relativity. These theories can be generally formulated on…
A problem of mass in macro- and microcosm has been considered from the single point of view on the basis of the law of conservation of energy. It is shown that in the conservative (absolutely closed) system all types of motion and…