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Related papers: Spacetime singularity resolution in Snyder noncomm…

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We study the Einstein static universe in the framework of Generalized Uncertainty Principle constructed by the Snyder non-commutative space. It is shown that the deformation parameter can induce an effective energy density subject to GUP…

General Relativity and Quantum Cosmology · Physics 2019-05-01 F. Darabi , K. Atazadeh

We provide a cosmological implementation of the evolutionary quantum gravity, describing an isotropic Universe, in the presence of a negative cosmological constant and a massive (preinflationary) scalar field. We demonstrate that the…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Francesco Cianfrani , Giovanni Montani , Fabrizio Pittorino

We investigate the possibility that the inflationary period in the early universe was preceded by a primordial stage of strong anisotropy. In particular we focus on the simplest model of this kind, where the spacetime is described by a…

High Energy Physics - Theory · Physics 2015-06-19 Jose J. Blanco-Pillado , Masato Minamitsuji

We present and analyze a gauge-invariant quantum theory of the Friedmann-Robertson-Walker universe with dust. We construct the reduced phase space spanned by gauge-invariant quantities by using the so-called relational formalism at the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Fumitoshi Amemiya , Tatsuhiko Koike

In this paper a quantum mechanical phase space picture is constructed for coarse-grained free quantum fields in an inflationary Universe. The appropriate stochastic quantum Liouville equation is derived. Explicit solutions for the phase…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Salman Habib

We show that a contracting universe which bounces due to quantum cosmological effects and connects to the hot big-bang expansion phase, can produce an almost scale invariant spectrum of perturbations provided the perturbations are produced…

High Energy Physics - Theory · Physics 2008-11-26 Patrick Peter , E. J. C. Pinho , Nelson Pinto-Neto

We investigate the impact of the deformed phase space associated with the quantum Snyder space on microphysical systems. The general Fermi-Dirac equation of state and specific corrections to it are derived. We put emphasis on…

General Relativity and Quantum Cosmology · Physics 2023-09-15 Anna Pachoł , Aneta Wojnar

Quasi-topological theories of gravity are known to resolve black-hole singularities. We investigate whether the same mechanism can remove cosmological singularities. Focusing on non-polynomial curvature quasi-topological gravities in $d=4$…

General Relativity and Quantum Cosmology · Physics 2026-03-19 Johanna Borissova , João Magueijo

Wheeler-DeWitt equation is applied to $k > 0$ Friedmann Robertson Walker metric with various types of matter. It is shown that if the Universe ends in the matter dominated era (e.g., radiation or pressureless gas) with zero cosmological…

High Energy Physics - Theory · Physics 2010-11-01 Jong Hyun Kung

We show that the non-supersymmetric AdS instability conjecture can point to how quantum gravity removes the initial Big Bang singularity, leading to a potential resolution for the past-incomplete inflationary universe. From the constraints…

High Energy Physics - Theory · Physics 2024-08-13 Cao H. Nam

The physical history of the Universe is completed by including the quantum planckian and trans-planckian phase before Inflation in the Standard Model of the Universe in agreement with observations. A new quantum precursor phase appears…

General Relativity and Quantum Cosmology · Physics 2019-12-23 Norma G. Sanchez

We extend the thermodynamic derivation of gravity in the Jacobson framework by generalizing the Clausius relation through a nontrivial entropy functional. We show that entropy deformations appear as modifications of the effective…

General Relativity and Quantum Cosmology · Physics 2026-04-14 H. R. Fazlollahi

We demonstrate how a classical Snyder-like phase space can be constructed in the Hamiltonian formalism for the free massless relativistic particle, for the two-time physics model and for the relativistic Newtonian gravitodynamic theory. In…

High Energy Physics - Theory · Physics 2007-05-23 W. Chagas-Filho

This work is an extension of the study into statistical mechanics of the early Universe that has been the subject in prior works of the author, the principal approach being the density matrix deformation. In the work it is demonstrated that…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. E. Shalyt-Margolin

The Liouville theorem states that the phase-space volume of an ensemble in a closed system remains constant. While gases of material particles can efficiently be cooled by sympathetic or laser cooling techniques, allowing for large…

We consider a polymer quantization of a free massless scalar field in a homogeneous and isotropic cosmological spacetime. This quantization method assumes that field translations are fundamentally discrete, and is related to but distinct…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-27 Golam Mortuza Hossain , Viqar Husain , Sanjeev S. Seahra

A model of a universe without big bang singularity is presented, which displaysanearly inflationary period ending just before a phase transition to a deflationary epoch. The model produces enough heavy particles so as to reheat the universe…

General Relativity and Quantum Cosmology · Physics 2016-09-05 Jaume de Haro , Emilio Elizalde

We present a new picture of the early universe in finite nonlocal quantum gravity, which is Weyl invariant at the classical and quantum levels. The high-energy regime of the theory consists of two phases, a Weyl invariant trans-Planckian…

General Relativity and Quantum Cosmology · Physics 2024-08-26 Leonardo Modesto , Gianluca Calcagni

In this work, we investigate inflationary cosmology using scalar field theory deformed by the generalized uncertainty principle (GUP) containing a linear momentum term. Apart from being consistent with the existence of a minimum measurable…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Ahmed Farag Ali , Mir Faizal , Mohammed M. Khalil

The $q$-theory formalism aims to describe the thermodynamics and dynamics of the deep quantum vacuum. The thermodynamics leads to an exact cancellation of the quantum-field zero-point-energies in equilibrium, which partly solves the main…

High Energy Physics - Theory · Physics 2017-10-25 F. R. Klinkhamer , M. Savelainen , G. E. Volovik