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The conception of gravity as an emergent phenomenon, rooted in the thermodynamics of spacetime, offers a radical departure from its geometric description. This paper investigates the emergence of cosmic space by synthesizing two key…

General Relativity and Quantum Cosmology · Physics 2026-01-05 Ahmad Sheykhi

We develop our recent suggestion that inflation may be made past eternal, so that there is no initial cosmological singularity or "beginning of time". Inflation with multiple vacua generically approaches a steady-state statistical…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Anthony Aguirre , Steven Gratton

This paper is devoted to discuss the difference in the thermodynamic entropy budget {\it per baryon} in each type of stellar object found in Universe. We track and discuss the actual {\it decrease} of the stored baryonic thermodynamic…

Solar and Stellar Astrophysics · Physics 2015-09-18 Marcio G. B. de Avellar , Rodrigo A. de Souza , Jorge E. Horvath

We consider a k-essence model in which a single scalar field can be responsible for both primordial inflation and the present observed acceleration of the cosmological background geometry, while also admitting a nonsingular de Sitter…

High Energy Physics - Theory · Physics 2024-01-17 Alexsandre L. Ferreira Junior , Nelson Pinto-Neto , Jorge Zanelli

In this paper, we propose a model in which an additional pressure due to the effects of the entropic force is added to the ideal fluid. Furthermore, we obtain the dynamic equation in the FRW universe which contains the quantum gravitational…

High Energy Physics - Theory · Physics 2016-03-08 Fei-Quan Tu , Yi-Xin Chen

The main consequences of de Sitter Special Relativity to the Standard Cosmological Model of Physical Cosmology are examined. The cosmological constant Lambda appears, in this theory, as a manifestation of the proper conformal current, which…

General Relativity and Quantum Cosmology · Physics 2010-01-08 R. Aldrovandi , J. G. Pereira

De Sitter spacetime is known to have a cosmological horizon that enjoys thermodynamic-like properties similar to those of a black hole horizon. In this note we show that a universal argument can be given for the entropy of de Sitter…

High Energy Physics - Theory · Physics 2009-10-31 Feng-Li Lin , Yong-Shi Wu

We consider the entropy associated with the large-scale structure of the Universe in the linear regime, where the Universe can be described by a perturbed Friedmann-Lema\^itre spacetime. In particular, we compare two different definitions…

General Relativity and Quantum Cosmology · Physics 2015-09-23 Giovanni Marozzi , Jean-Philippe Uzan , Obinna Umeh , Chris Clarkson

The growing cosmological interest of different entropy functions (like the Tsallis entropy, the R\'{e}nyi entropy, the Barrow entropy, the Sharma-Mittal entropy, the Kaniadakis entropy and the Loop Quantum gravity entropy) naturally raises…

General Relativity and Quantum Cosmology · Physics 2023-09-18 Sergei D. Odintsov , Simone D'Onofrio , Tanmoy Paul

A new definition of entropy is introduced using a model that simulates an expanding space-time compatible with the fundamental principle of cosmology. The entropy is obtained by mean of a state function that measures the variation of the…

General Physics · Physics 2024-05-01 Faycal Ben Adda

We consider the local physics of an open quantum system embedded in an expanding three-dimensional space $\mathbf x$, evolving in cosmological time $t$, weakly coupled to a massless quantum field. We derive the corresponding Markovian…

General Relativity and Quantum Cosmology · Physics 2023-12-22 Robert Alicki , Gabriela Barenboim , Alejandro Jenkins

In this work, we use an observational approach and dynamical system analysis to study the cosmological model recently proposed by Saridakis (2020), which is based on the modification of the entropy-area black hole relation proposed by…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-22 Genly Leon , Juan Magaña , A. Hernández-Almada , Miguel A. García-Aspeitia , Tomás Verdugo , V. Motta

The ER=EPR conjecture states that quantum entanglement between boundary degrees of freedom leads to the emergence of bulk spacetime itself. Although this has been tested extensively in String Theory for asymptotically anti-de Sitter…

High Energy Physics - Theory · Physics 2025-05-21 Suddhasattwa Brahma , Lucas Hackl , Moatsem Hassan , Xiancong Luo

We review the behaviour of the Gibbs' and conditional entropies in deterministic and stochastic systems and continue to a formulation appropriate for a stochastically perturbed system with delayed dynamics. The underlying question driving…

Mathematical Physics · Physics 2024-06-24 Michael C. Mackey , Marta Tyran-Kaminska

The stability of the de Sitter era of cosmic expansion in spatially curved homogeneous isotropic universes is studied. The source of the gravitational field is an imperfect fluid such that the parameters that characterize it may change with…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Luis P. Chimento , Alejandro S. Jakubi , Diego Pavon

Modern developments in nonequilibrium thermodynamics have significant implications for the origins of life. The reasons for this are closely related to a generalized version of the second law of thermodynamics recently found for entropy…

General Physics · Physics 2022-04-04 Gerald E. Marsh

In this paper we have discussed the modified gravity and scalar field DE model specifically DBI essence model with the analysis of thermodynamics during cosmological evolution. We have used the modified gravity with the form…

General Physics · Physics 2022-06-02 Shouvik Sadhukhan , Alokananda Kar , Surajit Chattopadhyay

By manipulating the integral expression for the proper radius $R_e$ of the cosmological event horizon (CEH) in a Friedmann-Robertson-Walker (FRW) universe, we obtain an analytical expression for the change $\dd R_e$ in response to a uniform…

General Physics · Physics 2015-05-20 Scott Funkhouser

In this paper, we investigate an important issue addressed by several approaches to quantum cosmology, like that based on loop quantum gravity and string theory: the existence of an arrow of time driving the cosmological evolution according…

General Relativity and Quantum Cosmology · Physics 2026-03-25 Carlos Silva , Renan Aragão , Francisco A. Brito

Recently Hollands, Wald and Zhang proposed a new formula for the entropy of a dynamical black hole. We lift this construction to the dynamical cosmological event horizon of an asymptotically de Sitter spacetime. By introducing a nontrivial…

General Relativity and Quantum Cosmology · Physics 2025-07-09 Jinan Zhao