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Related papers: Thermal and quantum superstring cosmologies

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In this paper, we start with black brane and construct specific space-time which violates hyperscaling. In order to obtain the string solution we apply Null-Melvin-Twist and $KK$-reduction. By using the difference action method we study…

High Energy Physics - Theory · Physics 2014-01-28 J. Sadeghi , B. Pourhassan , A. Asadi

We apply the gravity-thermodynamics conjecture, namely the first law of thermodynamics on the Universe horizon, but using the generalized Kaniadakis entropy instead of the standard Bekenstein-Hawking one. The former is a one-parameter…

General Relativity and Quantum Cosmology · Physics 2021-12-07 Andreas Lymperis , Spyros Basilakos , Emmanuel N. Saridakis

We study the thermal and curvature effect to spontaneous symmetry breaking in phi^4 theory. The effective potential is evaluated in D-dimensional static universe with positive curvature R X S^{D-1} or negative curvature R X H^{D-1}. It is…

High Energy Physics - Phenomenology · Physics 2009-11-11 T. Hattori , M. Hayashi , T. Inagaki , Y. Kitadono

We study the thermodynamics of Einstein gravity with vanishing cosmological constant subjected to conformal boundary conditions. Our focus is on comparing the series of subextensive terms to predictions from thermal effective field theory,…

High Energy Physics - Theory · Physics 2025-01-29 Batoul Banihashemi , Edgar Shaghoulian , Sanjit Shashi

In the present work, we study four-dimensional black strings in Horndeski models with translation invariance. Imposing that the scalar field depends on the string-generator coordinate, the Klein-Gordon equation admits a linear profile as a…

High Energy Physics - Theory · Physics 2023-11-30 Luis Guajardo

A general formalism for understanding the thermodynamics of horizons in spherically symmetric spacetimes is developed. The formalism reproduces known results in the case of black hole spacetimes. But its power lies in being able to handle…

General Relativity and Quantum Cosmology · Physics 2010-11-19 T. Padmanabhan

We study the thermodynamics associated to topological black hole solutions of AdS gravity coupled to nonlinear electrodynamics (Born-Infeld) in any dimension, using a background-independent regularization prescription for the Euclidean…

High Energy Physics - Theory · Physics 2008-11-26 Olivera Miskovic , Rodrigo Olea

We study the thermodynamics of a class of four-dimensional black hole solutions arising from the compactification of a higher-curvature gravity theory featuring an infinite tower of Lovelock-type invariants. For planar horizons, we identify…

General Relativity and Quantum Cosmology · Physics 2025-05-30 Adolfo Cisterna , Mokhtar Hassaine , Ulises Hernandez-Vera

In this paper, we derive exact black hole solutions within the framework of fourth-order quasitopological gravity (4QTG) coupled to power-law Maxwell electrodynamics in five-dimensional spacetimes. We explore the thermodynamic properties of…

General Relativity and Quantum Cosmology · Physics 2025-03-31 A. Bazrafshan , M. Ghanaatian , P. Mirsalari , Gh. Forozani

The thermodynamics-gravity conjecture reveals that one can derive the gravitational field equations by using the first law of thermodynamics and vice versa. Considering the entropy associated with the horizon in the form of non-extensive…

General Relativity and Quantum Cosmology · Physics 2021-11-04 Mahnaz Asghari , Ahmad Sheykhi

In the context of the Relativistic Quantum Geometry formalism, where the cosmological constant is promoted to a dynamical variable by attributing it a geometric interpretation as a result of a flux on the boundary of a manifold and…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Juan Ignacio Musmarra , Claudia Moreno , Rafael Hernández-Jiménez

We consider braneworld scenarios including the leading correction to the Einstein-Hilbert action suggested by superstring theory, the Gauss-Bonnet term. We obtain and study the complete set of equations governing the cosmological dynamics.…

High Energy Physics - Theory · Physics 2009-11-07 Cristiano Germani , Carlos F. Sopuerta

There are two strong clues about the quantum structure of spacetime and the gravitational dynamics, which are almost universally ignored in the conventional approaches to quantize gravity. The first clue is that null surfaces exhibit…

General Relativity and Quantum Cosmology · Physics 2020-01-17 T. Padmanabhan

Recent work has studied the thermodynamics of gravity subjected to conformal boundary conditions, where the trace of the extrinsic curvature $K$ and the conformal class of metrics are kept fixed. The case $K < 0$ seems tied to solutions…

High Energy Physics - Theory · Physics 2025-03-25 Batoul Banihashemi , Edgar Shaghoulian , Sanjit Shashi

In this paper, we first obtain the energy density by the approach of the new agegraphic dark energy model, and then the $f(T,B)$ gravity model is studied as an alternative to the dark energy in a viscous fluid by flat-FRW background, in…

General Relativity and Quantum Cosmology · Physics 2020-06-17 A. Pourbagher , Alireza Amani

We construct a new class of exact and stable superstring solutions based on $N=4$ superconformal world-sheet symmetry. In a subclass of these, the full spectrum of string excitations is derived in a modular-invariant way. In the weak…

High Energy Physics - Theory · Physics 2009-10-28 I. Antoniadis , S. Ferrara , C. Kounnas

We present a quantum description of black holes given by coherent states of gravitons sourced by a matter core. The expected behaviour in the weak-field region outside the horizon is recovered, with arbitrarily good approximation, but the…

General Relativity and Quantum Cosmology · Physics 2022-09-09 Roberto Casadio

Gravity is so different from other fundamental forces that it is now essentially treated as a non-fundamental force of entropic origin. A number of good studies have been carried out in this direction. Quantum gravity has also significantly…

General Relativity and Quantum Cosmology · Physics 2020-12-11 M. Hameeda , Q. Gani , B. Pourhassan , M. C. Rocca

The linear cosmological perturbation theory of an almost homogeneous and isotropic perfect fluid universe is reconsidered and formally simplified by introducing new covariant and gauge-invariant variables with physical interpretations on…

General Relativity and Quantum Cosmology · Physics 2011-07-19 Winfried Zimdahl

The holographic solution is a new exact solution to the Einstein field equations. It describes a compact self-gravitating object with properties similar to a black hole. Its entropy and temperature at infinity are proportional to the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Michael Petri