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It has been often conjectured that the correct theory of quantum gravity will act as a UV regulator in the low energy limit of quantum field theory. Earlier work has shown that if the path integral defining the quantum field theory…

High Energy Physics - Theory · Physics 2007-05-23 A. Smailagic , E. Spallucci , T. Padmanabhan

Motivated by the nonextensive nature of entropy in gravitational context and the Gauge/Gravity duality, black hole thermodynamics has been attracting intense emphasis in the literature. Along the present work, we investigate some features…

General Relativity and Quantum Cosmology · Physics 2023-10-17 F. Barzi , H. El Moumni , K. Masmar

The Modified Chaplygin Gas (MCG) model is revisited to examine its ability to describe the full cosmic evolution within a single framework. Because the field equations are highly nonlinear, no closed analytical solution for the scale factor…

General Relativity and Quantum Cosmology · Physics 2025-12-23 D. Panigrahi , S. Chatterjee , B. C. Paul

We study some aspects of dynamical compactification scenario where stabilisation of extra dimensions occurs due to presence the Gauss-Bonnet term and non-zero spatial curvature. In the framework of the model under consideration there exists…

General Relativity and Quantum Cosmology · Physics 2021-05-12 Dmitry Chirkov , Sergey A. Pavluchenko

We study the potential effects of spacetime non-metricity in cosmology. In the spirit of Einstein-Cartan gravity, but with non-metricity replacing torsion, we consider the Einstein-Hilbert action and assume zero torsion. Adopting certain…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Damianos Iosifidis , Ioannis Georgios Vogiatzis , Christos G. Tsagas

We investigate the effects of viscosity terms depending on the Hubble parameter and its derivatives in the dark energy equation of state. Such terms are possible if dark energy is a fictitious fluid originating from corrections to the…

Astrophysics · Physics 2010-04-06 S. Capozziello , V. F. Cardone , E. Elizalde , S. Nojiri , S. D. Odintsov

Thermal history of the string universe based on the Brandenberger and Vafa's scenario is examined. The analysis thereby provides a theoretical foundation of the string universe scenario. Especially the picture of the initial oscillating…

High Energy Physics - Theory · Physics 2009-10-22 H. Cateau , K. Sumiyoshi

The discrete quantum geometric effects play an important role in dynamical evolution in the loop quantum cosmology. These effects which are significant at the high energies lead to the quadratic energy density modifications to the Friedmann…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Parampreet Singh

We consider a Friedmann model of the universe with bulk viscous matter and radiation as the cosmic components. We study the asymptotic properties in the equivalent phase space by considering the three cases for the bulk viscous coefficient…

General Relativity and Quantum Cosmology · Physics 2019-05-13 Athira Sasidharan , Titus K Mathew

In a natural extension of the relativity principle we argue that a quantum theory of gravity involves two fundamental scales associated with both dynamical space-time as well as dynamical momentum space. This view of quantum gravity is…

High Energy Physics - Theory · Physics 2015-06-19 Laurent Freidel , Robert G. Leigh , Djordje Minic

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.…

General Relativity and Quantum Cosmology · Physics 2024-10-08 S. Davood Sadatian , S. Mohamad Reza Hosseini

We consider some consequences of describing the gauge and matter degrees of freedom in our universe by open strings, as suggested by the braneworld scenario. We focus on the geometric effects described by the open string metric and…

High Energy Physics - Phenomenology · Physics 2009-11-07 Katherine Freese , Matthew Lewis , Jan Pieter van der Schaar

We study the statistical mechanics of the early radiation dominated universe in the context of a generalized uncertainty principle which supports the existence of a minimal length scale. Utilizing the resultant modified thermodynamical…

General Relativity and Quantum Cosmology · Physics 2016-01-22 B. Vakili , M. A. Gorji

Dark energy has a dramatic effect on the dynamics of the universe, causing the recently discovered acceleration of the expansion. The dynamics are also central to the behavior of the growth of large scale structure, offering the possibility…

Astrophysics · Physics 2009-11-07 Eric V. Linder , Adrian Jenkins

In this paper we construct a stringy embedding of the dark bubble model of an expanding 4D cosmology with the help of branes rotating in extra dimensions. The universe rides a bubble which has nucleated in an unstable higher dimensional…

High Energy Physics - Theory · Physics 2023-02-08 Ulf Danielsson , Oscar Henriksson , Daniel Panizo

The observation in the universe of a small but positive vacuum energy strongly suggests, in the string landscape picture, that there will ultimately be a phase transition to an exactly supersymmetric universe. This ground state or "true…

High Energy Physics - Phenomenology · Physics 2007-05-23 L. Clavelli

A brief review of main features of the new approach named ``quantum geometrodynamics in extended phase space'' is given and its possible prospects are discussed. Gauge degrees of freedom are treated as a subsystem of the Universe which…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. P. Shestakova

The superradiant growth of massive vector fields in rotating black hole spacetimes has garnered significant attention in recent literature. However, the majority of these studies overlook the influence of a cosmological constant, which…

General Relativity and Quantum Cosmology · Physics 2024-06-18 Shaun David Brocus Fell , Lavinia Heisenberg

We point out that, due to the nonlinearity of the Einstein equations, a homogeneous approximation in cosmology leads to the appearance of an additional term in the Friedmann equation. This new term is associated with the spatial…

Astrophysics · Physics 2015-06-24 Gyula Bene , Viktor Czinner , Matyas Vasuth

This work examines the cosmological implications of two functional forms of $f(R,T) = R + \alpha T^n$ gravity: for two different value of $n $ where $n=1$ and $n\neq 1$, and $\alpha$ and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-24 Mustapha Lamaaoune