English
Related papers

Related papers: Spacetime singularity resolution in Snyder noncomm…

200 papers

We establish the nonexistence of nontrivial ancient solutions to the nonlinear heat equation $u_t=\Delta u+|u|^{p-1}u$ which are smaller in absolute value than the self-similar radial singular steady state, provided that the exponent $p$ is…

Analysis of PDEs · Mathematics 2020-08-18 Christos Sourdis

A static non-singular 10-dimensional closed Friedmann universe of Planck size, filled with a perfect fluid with an equation of state with w = -2/3, can arise spontaneously by a quantum fluctuation from nothing in 11-dimensional spacetime. A…

General Relativity and Quantum Cosmology · Physics 2009-11-11 T. R. Mongan

The initial cosmological singularity in the framework of the general theory of relativity is resolved by introducing the effect of the uncertainty principle of quantum theory without violating conventional laws of physics. A plausible…

Astrophysics · Physics 2009-11-07 D. C. Choudhury

In this paper, vacuum and singularity formation are considered for compressible Euler equations with time-dependent damping. For $1<\gamma\leq 3$, by constructing some new control functions ingeniously, we obtain the lower bounds estimates…

Analysis of PDEs · Mathematics 2022-01-21 Ying Sui , Weiqiang Wang , Huimin Yu

Quintessential inflation provides a unified description of the early and late accelerated phases of the Universe, linking the inflationary epoch to the present-day dark energy-dominated era through a single scalar degree of freedom. In this…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 Jamerson Rodrigues , Gabriel Rodrigues , Felipe B. M. dos Santos , Simony Santos da Costa , Jailson Alcaniz

This paper continues a study of field theories specified for the nonuniform lattice in the finite-dimensional hypercube with the use of the earlier described deformation parameters. The paper is devoted to spontaneous breakdown and…

High Energy Physics - Theory · Physics 2009-11-10 A. E. Shalyt-Margolin

Assuming that the background geometry is filled with free gas consisting of matter and radiation and no phase transitions being occurred in the early Universe, we discuss the thermodynamics of this {\it closed} system using classical…

General Relativity and Quantum Cosmology · Physics 2015-05-30 A. Tawfik , H. Magdy

In a primordial universe pre(post)-inflationary era , there could be phases of early universe made of cold gas baryons, radiation and early post inflationary cosmological constant. I showed that in the baryonic epoch, the quantum vacuum is…

General Relativity and Quantum Cosmology · Physics 2021-01-11 Davood Momeni

We construct a class of charged, rotating solutions of (n+1)-dimensional Einstein-Maxwell-dilaton gravity with Liouville-type potentials and investigate their properties. These solutions are neither asymptotically flat nor (anti)-de Sitter.…

High Energy Physics - Theory · Physics 2008-11-26 A. Sheykhi , M. H. Dehghani , N. Riazi , J. Pakravan

We show that there exist solutions to the semi-classical gravity equations in de Sitter spacetime sourced by the renormalised stress-energy tensor of a free Klein-Gordon field. For the massless scalar, solutions exist for every possible…

General Relativity and Quantum Cosmology · Physics 2019-10-02 Benito A. Juárez-Aubry

We canonically quantize the dynamics of the brane universe embedded into the five-dimensional Schwarzschild-anti-deSitter bulk space-time. We show that in the brane-world settings the formulation of the quantum cosmology, including the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Boyarsky , A. Neronov , I. Tkachev

Two spatial regions $B$ and $R$ are hyperentangled if the generalized entropy satisfies $S_{\text{gen}}^{B\cup R}<S_{\text{gen}}^R$. If in addition all future (or all past) directed inward null shape deformations of $B$ decrease…

High Energy Physics - Theory · Physics 2023-03-30 Raphael Bousso , Arvin Shahbazi-Moghaddam

The question of whether the universe is eternal or if it had a singular moment of creation is deeply intriguing. Although different versions of steady state and oscillatory models of eternal universe have been envisaged, empirical evidence…

General Relativity and Quantum Cosmology · Physics 2020-03-09 Karthik H. Shankar

Motivated by the works on Equivalence Principle in the context of linear Generalized Uncertainty Principle and, independently, in the context of quadratic Generalized Uncertainty Principle, we expand these endeavors in the context of…

High Energy Physics - Theory · Physics 2022-08-11 Elias C. Vagenas , Ahmed Farag Ali , Mohammed Hemeda , Hassan Alshal

We study in some detail the master equation, and its solution in a simplified case modelling flavour oscillations of a two-level system, stemming from the Liouville-string approach to quantum space time foam. In this framework we discuss…

High Energy Physics - Theory · Physics 2013-05-29 Nick Mavromatos , Sarben Sarkar

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas

We study the quantum dynamics of de Sitter space formulated as a minisuperspace model with flat spatial hypersurfaces in unimodular gravity, both in the Wheeler-DeWitt approach and in loop quantum cosmology (LQC). Time evolution is defined…

General Relativity and Quantum Cosmology · Physics 2025-07-14 Steffen Gielen , Rita B. Neves

Among the many disparate approaches towards quantum gravity, the reduction of spacetime dimension in the ultraviolet regime is expected to be a common thread. The dimensionality of spacetime can be defined in various contexts. The spectral…

General Relativity and Quantum Cosmology · Physics 2022-04-26 Vikramaditya Mondal

We provide a realisation of a singularity-free inflationary universe in the form of a simple cosmological model dominated at early times by a single minimally coupled scalar field with a physically based potential. The universe starts…

General Relativity and Quantum Cosmology · Physics 2008-11-26 George F. R. Ellis , Jeff Murugan , Christos G. Tsagas

We establish Liouville type theorems in the whole space and in a half-space for parabolic problems without scale invariance. To this end, we employ two methods, respectively based on the corresponding elliptic Liouville type theorems and…

Analysis of PDEs · Mathematics 2024-10-01 Pavol Quittner , Philippe Souplet