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Related papers: Thermodynamics in new model of loop quantum cosmol…

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In this work, we have discussed the Maxwell's electrodynamics in non-linear forms in FRW universe. The energy density and pressure for non-linear electrodynamics have been written in the electro-magnetic universe. The Einstein's field…

General Physics · Physics 2012-08-29 Tanwi Bandyopadhyay , Ujjal Debnath

A thermodynamic description of cosmological spacetimes may provide insights into the fundamentals of the cosmic evolution that remain otherwise obscure, similar to `black hole thermodynamics'. We investigate the thermodynamic properties of…

General Relativity and Quantum Cosmology · Physics 2026-03-31 Dipayan Mukherjee , Harkirat Singh Sahota , Swati Gavas

In a recent article we have introduced Friedmann thermodynamics, where certain geometric parameters in Friedmann models are treated like their thermodynamic counterparts (temperature, entropy, Gibbs potential etc.). This model has the…

General Relativity and Quantum Cosmology · Physics 2008-04-02 Selcuk S. Bayin

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 concept of effective dynamics has proven successful in LQC, a loop-inspired quantization of cosmological spacetimes. We apply the same idea of its derivation in LQC to the full theory, by computing the expectation value of the scalar…

General Relativity and Quantum Cosmology · Physics 2018-09-17 Andrea Dapor , Klaus Liegener

The perfect Planck spectrum of the observed cosmic microwave background radiation indicates that our universe must be in thermal equilibrium. The dark sector of the universe should also be in the same equilibrium state with dark matter and…

General Physics · Physics 2016-12-14 Ti-Pei Li , Mei Wu

We construct and study Loop Quantum Cosmology (LQC) when the Barbero-Immirzi parameter takes the complex value $\gamma=\pm i$. We refer to this new quantum cosmology as complex Loop Quantum Cosmology. We proceed in making an analytic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Jibril Ben Achour , Julien Grain , Karim Noui

We assume the non-flat Friedmann-Robertson-Walker (FRW) Universe as a thermodynamical system. We assume the cosmological horizon as a inner trapping horizon which is treated as dynamical apparent horizon of FRW Universe. We write the…

General Relativity and Quantum Cosmology · Physics 2020-10-06 Ujjal Debnath

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

We present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. We extract the modified Friedmann equations, which contain new terms quantified by the non-extensive…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Shin'ichi Nojiri , Sergei D. Odintsov , Emmanuel N. Saridakis

There are now evidences that the cosmological constant $\Lambda$ has a non-zero positive value. Alternative scenarios to a pure cosmological constant model are provided by quintessence, an effective negative pressure fluid permeating the…

Astrophysics · Physics 2008-11-26 Antonio Vale , Jose' P. S. Lemos

We study the late time cosmological evolution of $f(R)$ theories of modified gravity, with the matter content of the universe being that of collisional self interacting matter. We assume that the universe is described by a flat…

General Relativity and Quantum Cosmology · Physics 2015-06-22 V. K. Oikonomou , N. Karagiannakis

To clarify a holographic modified thermodynamic relation, the present study applies a general formulation for cosmological equations in a flat FLRW universe to the first law of thermodynamics, using the Bekenstein-Hawking entropy…

General Relativity and Quantum Cosmology · Physics 2025-01-22 Nobuyoshi Komatsu

We investigate the laws of thermodynamics in an accelerating universe driven by dark energy with a time-dependent equation of state. In the case we consider that the physically relevant part of the Universe is that envelopped by the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Bin Wang , Yungui Gong , Elcio Abdalla

In this paper, we study thermodynamical properties of the apparent horizon in a universe governed by quasi-topological gravity. Our aim is twofold. First, by using the variational method we derive the general form of Friedmann equation in…

High Energy Physics - Theory · Physics 2015-06-16 M. H. Dehghani , A. Sheykhi , R. Dehghani

Our aim is studying the thermodynamics of cosmological models including initial and final de-Sitter eras. For this propose, bearing Cai-Kim temperature in mind, we investigate the thermodynamic properties of a dark energy candidate with…

General Relativity and Quantum Cosmology · Physics 2015-08-24 H. Moradpour , M. T. Mohammadi Sabet , A. Ghasemi

Quantum effects are expected to modify the cosmological dynamics of the early universe while maintaining some (potentially discrete) notion of space-time structure. In one approach, loop quantum cosmology, current models are shown here to…

General Relativity and Quantum Cosmology · Physics 2026-04-29 Martin Bojowald , Manuel Diaz , Erick I. Duque

We explore the derivation of the Friedmann equations from a thermodynamic perspective, applying the unified first law of thermodynamics to the apparent horizon of a flat Friedmann-Lema\^itre-Robertson-Walker (FLRW) universe. We extend this…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Víctor H. Cárdenas , Miguel Cruz , Samuel Lepe

We study the thermodynamics of a non-singular black hole model with effective quantum corrections motivated by Loop Quantum Gravity (LQG). The effective geometry has a transition surface that connects trapped and anti-trapped regions with…

General Relativity and Quantum Cosmology · Physics 2025-09-03 F. G. Menezes , H. A. Borges , I. P. R. Baranov , S. Carneiro

The pivotal point of the paper is to discuss the behavior of temperature, pressure, energy density as a function of volume along with determination of caloric EoS from following two model: $w(z)=w_{0}+w_{1}\ln(1+z)$ & $…

General Physics · Physics 2015-03-09 Sridip Pal , Ritabrata Biswas