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Related papers: Friedmann Thermodynamics and the Geometry of the U…

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We review the main aspects of geometrothermodynamics, a formalism that uses contact geometry and Riemannian geometry to describe the properties of thermodynamic systems. We show how to handle in a geometric way the invariance of classical…

General Relativity and Quantum Cosmology · Physics 2023-07-26 Orlando Luongo , Hernando Quevedo

The large-scale structure of the Universe is well approximated by the Friedmann equations, parametrized by several energy densities which can be observationally inferred. A natural question to ask is: How different would the Universe be if…

General Relativity and Quantum Cosmology · Physics 2025-01-20 Arthur G. Suvorov

A generalized entropy arising in the context of superstatistics is obtained for an ideal gas. The curvature scalar associated to the thermodynamic space generated by this modified entropy is calculated using two formalisms of the geometric…

Statistical Mechanics · Physics 2018-04-18 J. L. López , O. Obregón , J. Torres-Arenas

Using the formalism of geometrothermodynamics to derive a fundamental thermodynamic equation, we construct a cosmological model in the framework of relativistic cosmology. In a first step, we describe a system without thermodynamic…

General Relativity and Quantum Cosmology · Physics 2017-08-25 Christine Gruber , Hernando Quevedo

The formal structure of geometrical thermodynamics is reviewed with particular emphasis on the geometry of equilibria submanifolds. On these submanifolds thermodynamic metrics are defined as the Hessian of thermodynamic potentials. Links…

Mathematical Physics · Physics 2007-05-23 Manuel Santoro , Albert S. Benight

The research work in the thesis is focused on the thermodynamic analysis of cosmological models, especially the models that explain late-time cosmic acceleration. According to the cosmological principle, the universe is spatially…

General Relativity and Quantum Cosmology · Physics 2024-06-05 Tanima Duary

Geometrothermodynamics is a geometric theory which combines thermodynamics with contact and Riemannian geometry. In this work we use the formalism of geometrothermodynamics to infer cosmological models which predict the observed speed up.…

General Relativity and Quantum Cosmology · Physics 2025-11-12 Alessandro Bravetti , Orlando Luongo

It has previously been shown that it is more general to describe the evolution of the universe based on the emergence of the space and the energy balance relation. Here we investigate the thermodynamic properties of the universe described…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Fei-Quan Tu , Yi-Xin Chen , Qi-Hong Huang

In this paper we describe the evolution of the Universe in terms of the Friedmann equation, which takes into account of the composition and geometry of the Universe. The dependence of the solution on the geometry and composition for…

Popular Physics · Physics 2020-11-02 Vinicius S. Aderaldo , Victor P. Goncalves

The fact that one can associate thermodynamic properties with horizons brings together principles of quantum theory, gravitation and thermodynamics and possibly offers a window to the nature of quantum geometry. This review discusses…

General Relativity and Quantum Cosmology · Physics 2015-05-14 T. Padmanabhan

We present the fundamentals of geometrothermodynamics, an approach to study the properties of thermodynamic systems in terms of differential geometric concepts. It is based, on the one hand, upon the well-known contact structure of the…

Chemical Physics · Physics 2009-11-11 Hernando Quevedo

We describe the evolution of the early and late universe from thermodynamic considerations, using the generalized non-extensive Tsallis entropy with a variable exponent. A new element in our analysis is the inclusion of a bulk viscosity in…

General Relativity and Quantum Cosmology · Physics 2021-02-10 I. Brevik , A. V. Timoshkin

In this paper, we examine the thermodynamic features of an exotic fluid known as modified cosmic Chaplygin gas in the context of homogeneous isotropic universe model. For this purpose, the behavior of physical parameters are discussed that…

General Relativity and Quantum Cosmology · Physics 2018-10-05 M. Sharif , Sara Ashraf

Assuming that the background geometry is filled with free gas consisting of matter and radiation and no phase transitions being occurred in the early Universe, we discuss the thermodynamics of this {\it closed} system using classical…

General Relativity and Quantum Cosmology · Physics 2015-05-30 A. Tawfik , H. Magdy

In this paper, the generalized second law (GSL) of thermodynamics and entropy is revisited in the context of cosmological models in Gauss-Bonnet gravity with the boundary of the universe is assumed to be enclosed by the dynamical apparent…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Hossein Farajollahi , Amin Salehi

Geometry of the universe has always intrigued mathematicians and cosmologists. Recent results from the Wilkinson Microwave Anisotropy Project (WMAP) indicate that the visible universe is incredibly flat. This apparent flatness could be due…

General Relativity and Quantum Cosmology · Physics 2013-09-24 Selcuk S. Bayin

The aim here is to provide a set of equations for cosmology in terms of information and thermodynamical parameters. The method we implement in order to describe the universe is a development of Padmanabhan\rq{}s approach which is based on…

General Relativity and Quantum Cosmology · Physics 2015-11-04 M. Hashemi , S. Jalalzadeh , S. Vasheghani Farahani

For the Fermi gas filling the space inside a cubic cavity of a fixed volume, at arbitrary temperatures and number of particles, the thermodynamic characteristics are calculated, namely: entropy, thermodynamic potential, energy, pressure,…

Quantum Physics · Physics 2024-08-08 Yu. M. Poluektov , A. A. Soroka

As a point of departure it is suggested that Quantum Cosmology is a topological concept independent from metrical constraints. Methods of continuous topological evolution and topological thermodynamics are used to construct a cosmological…

General Relativity and Quantum Cosmology · Physics 2007-05-23 R. M. Kiehn

Applying the first law of thermodynamics to the apparent horizon of a Friedmann-Robertson-Walker universe and assuming the geometric entropy given by a quarter of the apparent horizon area, we derive the Friedmann equations describing the…

High Energy Physics - Theory · Physics 2009-11-11 Rong-Gen Cai , Sang Pyo Kim
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