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相关论文: Cosmic Hysteresis in $f(R)$ Gravity: A Thermodynam…

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We study the emergence of cosmic hysteresis in cyclic bouncing universes within the framework of analytically reconstructed $f(R)$ gravity. Using exact bouncing scale factor solutions of exponential and power-law forms, we reconstruct the…

广义相对论与量子宇宙学 · 物理学 2025-08-15 Aritra Sanyal , Praveen Kumar Dhankar , Albert Munyeshyaka , Safiqul Islam , Farook Rahaman

We investigate the emergence of cosmic hysteresis in cyclic and bouncing cosmologies within the framework of reconstructed $f(T)$ gravity. In contrast to curvature-based modifications of General Relativity, teleparallel gravity attributes…

广义相对论与量子宇宙学 · 物理学 2026-02-19 Aritra Sanyal , Praveen Kumar Dhankar , Albert Munyeshyaka , Safiqul Islam , Farook Rahaman , Behnam Pourhassan

Cosmological hysteresis is a purely thermodynamical phenomenon caused by the gradient in pressure, hence the characteristic equation of state during the expansion and contraction phases of the universe are different, provided that the…

高能物理 - 理论 · 物理学 2016-03-10 Sayantan Choudhury , Shreya Banerjee

Cosmological hysteresis, has interesting and vivid implications in the scenario of a cyclic bouncy universe. This, purely thermodynamical in nature, is caused by the asymmetry in the equation of state parameter during expansion and…

高能物理 - 理论 · 物理学 2017-11-28 Sayantan Choudhury , Shreya Banerjee

Hysteresis is a phenomenon occurring naturally in several magnetic and electric materials in condensed matter physics. When applied to cosmology, aka cosmological hysteresis, has interesting and vivid implications in the scenario of a…

高能物理 - 理论 · 物理学 2016-04-12 Sayantan Choudhury , Shreya Banerjee

In this study, we explore the thermodynamic aspects of a modified version of Rastall's gravity theory and its implications for cosmological scenarios. We analyze the role of non-conserved energy-momentum tensor equations and investigate…

广义相对论与量子宇宙学 · 物理学 2025-12-01 José A. C. Nogales , K. Luz-Burgoa , Laysa G. Martins

The paper deals with $f(R)$ gravity theory in the background of inhomogeneous FLRW--type space time model. With proper choice of the inhomogeneous metric function it is possible to have an emergent scenario for the $f(R)$--cosmology.…

广义相对论与量子宇宙学 · 物理学 2018-11-14 Dipanjana Das , Sourav Dutta , Subenoy Chakraborty

A Universe filled with a homogeneous scalar field exhibits `Cosmological hysteresis'. Cosmological hysteresis is caused by the asymmetry in the equation of state during expansion and contraction. This asymmetry results in the formation of a…

广义相对论与量子宇宙学 · 物理学 2013-05-30 Varun Sahni , Aleksey Toporensky

We investigate cyclic and singularity-free evolutions in a universe governed by Lagrange-multiplier modified gravity, either in scalar-field cosmology, as well as in $f(R)$ one. In the scalar case, cyclicity can be induced by a suitably…

宇宙学与河外天体物理 · 物理学 2011-01-18 Yi-Fu Cai , Emmanuel N. Saridakis

In this paper, we investigate and analyze the cosmological dynamics of the universe, with an effect of modified $f(R)$ gravity emerging at cosmological scale. We choose the Einstein frame as a physical frame. We consider phase portraits of…

天体物理学 · 物理学 2007-05-23 Daris Samart

In this paper, we study $F(R)$ gravity by Hu-Sawicki model in Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) background. The Friedmann equations are calculated by modified gravity action, and then the obtained Friedmann equations are…

广义相对论与量子宇宙学 · 物理学 2016-05-25 Ali R. Amani

In $f(T)$ gravity, the theory modifies the gravitational action by introducing a function of the torsion scalar $T$. This approach allows for a different treatment of gravity than general relativity, particularly in cosmological contexts.…

广义相对论与量子宇宙学 · 物理学 2024-10-08 S. Davood Sadatian , S. Mohamad Reza Hosseini

We discuss the cosmology of recently proposed Horava-Lifshitz f(R) gravity. In particular, we derive the modified Hubble equation that reduces to the standard HL gravity case in appropriate limit. We show how the bounce solutions in this…

宇宙学与河外天体物理 · 物理学 2012-04-13 Sayan K. Chakrabarti , Koushik Dutta , Anjan A. Sen

The present work analyzes the various conditions in which there can be a bouncing universe solution in f(R) gravity. In the article an interesting method, to analyze the bouncing FRW solutions in a spatially flat universe using f(R) gravity…

广义相对论与量子宇宙学 · 物理学 2014-12-09 Niladri Paul , Saikat Nil Chakrabarty , Kaushik Bhattacharya

The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of $f(\mathcal{Q}, \mathcal{C})$ gravity, where $\mathcal{Q}$ denotes non-metricity and $\mathcal{C}$ indicates the boundary term. To…

广义相对论与量子宇宙学 · 物理学 2025-08-12 M. Sharif , M. Zeeshan Gul , Ahmad Nawaz

In this paper, we analyze the modified $f(\mathcal{R})$ gravity models in Friedmann--Lema\^{\i}tre--Robertson--Walker (FLRW) background. The actions of bouncing cosmology are studied under consideration of different viable models in…

广义相对论与量子宇宙学 · 物理学 2021-02-18 M. Ilyas , W. U. Rahman

In this study, we explore the dynamics of the universe using a modified gravity model represented by $f(R, G, T)$, where $R$ is the Ricci scalar, $G$ is the Gauss-Bonnet invariant, and $T$ is the trace of the stress-energy tensor. The model…

广义相对论与量子宇宙学 · 物理学 2025-03-27 Farzad Milani

The paper deals with cosmology in modified f(T) gravity theory. With some phenomenological choices for the function f(T) it is possible to have cosmological solutions describing different phases of the evolution of the Universe for the…

广义相对论与量子宇宙学 · 物理学 2020-11-03 Akash Bose , Subenoy Chakraborty

We explore the possibility of realizing a non-singular bounce in the early universe within the framework of modified gravity with spacetime torsion. In Einstein Cartan theory, torsion is embedded in the spacetime by adding an antisymmetric…

广义相对论与量子宇宙学 · 物理学 2026-01-21 Sonej Alam , Somasri Sen , Soumitra Sengupta

We study a cosmological setup consisting of a FRW metric as the background geometry with a massless scalar field in the framework of classical polymerization of a given dynamical system. To do this, we first introduce the polymeric…

广义相对论与量子宇宙学 · 物理学 2014-10-21 B. Vakili , K. Nozari , V. Hosseinzadeh , M. A. Gorji
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