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Related papers: $f(T)$ cosmology: From Pseudo-Bang to Pseudo-Rip

200 papers

The paper deals with $f(R)$ gravity theory in the background of inhomogeneous FLRW--type space time model. With proper choice of the inhomogeneous metric function it is possible to have an emergent scenario for the $f(R)$--cosmology.…

General Relativity and Quantum Cosmology · Physics 2018-11-14 Dipanjana Das , Sourav Dutta , Subenoy Chakraborty

In a previous paper we proposed a new approach to the beginning of inflation -- a lingering universe. The universe begins in a lingering state with a nearly vanishing Hubble parameter. This calls into question the absolute age of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-09 Brandon Melcher , Arnab Pradhan , Scott Watson

In Loop Quantum Gravity mathematically rigorous models of full quantum gravity were proposed. In this paper we study a cosmological sector of one of the models describing quantum gravity with positive cosmological constant coupled to…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Marcin Kisielowski

We propose a new five-parameter entropy function that proves to be singular-free during the entire cosmic evolution of the universe, and at the same time, also generalizes the Tsallis, Barrow, R\'{e}nyi, Sharma-Mittal, Kaniadakis and Loop…

General Relativity and Quantum Cosmology · Physics 2022-12-13 Sergei D. Odintsov , Tanmoy Paul

By studying first a new decelerating sudden future singularity (SFS) universe we report finding a novel type of cosmological singularity which we dub a finite time pseudo-rip (FTPR) because unlike for a pseudo-rip, it happens in the finite…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Mariusz P. Dąbrowski , Teodor Borislavov Vasilev

The cosmology of "Spontaneous Creation of the Universe Ex Nihilo" and the cosmology of the Symmetrical Relativity offer proposals to explain the creation and evolution of the universe. In essence they are still very distinct. However, we…

General Physics · Physics 2020-10-16 Cláudio Nassif Cruz , Fernando Antônio da Silva

The study of particle creation phenomena at the expense of the gravitational field is of great research interest. It might solve the cosmological puzzle single-handedly, without the need for either dark energy or the modified theory of…

General Relativity and Quantum Cosmology · Physics 2018-06-26 Abhik Kumar Sanyal , Subhra Debnath

An oscillating universe cycles through a series of expansions and contractions. We propose a model in which ``phantom'' energy with a supernegative pressure ($p < - \rho$) grows rapidly and dominates the late-time expanding phase. The…

Astrophysics · Physics 2008-03-29 Katherine Freese , Matthew G. Brown , William H. Kinney

Various cosmological models in frames of $F(T)$ gravity are considered. The general scheme of constructing effective dark energy models with various evolution is presented. It is showed that these models in principle are compatible with…

General Relativity and Quantum Cosmology · Physics 2015-06-16 Artyom V. Astashenok

In the present mainstream cosmology, matter and spacetime emerged from a singularity and evolved through four distinct periods: early inflation, radiation, dark matter and late-time inflation (driven by dark energy). During the radiation…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-02 E. L. D. Perico , J. A. S. Lima , Spyros Basilakos , Joan Sola

The discovery of universe's late-time acceleration and dark energy has overseen a great deal of research into cosmological singularities and particularly future singularities. Perhaps the most extreme of such singlarities is the big rip,…

General Relativity and Quantum Cosmology · Physics 2024-07-25 Oem Trivedi , Alexander V. Timoshkin

Recent studies of QFT in cosmological spacetime indicate that the speeding up of the present universe may not just be associated with a rigid cosmological term but with a running one that evolves with the expansion rate:…

General Relativity and Quantum Cosmology · Physics 2025-04-04 Joan Solà Peracaula , Cristian Moreno-Pulido , Alex González-Fuentes

Inflationary cosmology attempts to provide a natural explanation for the flatness and homogeneity of the observable universe. In the context of reversible (unitary) evolution, this goal is difficult to satisfy, as Liouville's theorem…

High Energy Physics - Theory · Physics 2010-07-09 Sean M. Carroll , Heywood Tam

We demonstrate that finite time singularities of Type IV can be consistently incorporated in the Universe's cosmological evolution, either appearing in the inflationary era, or in the late-time regime. While using only one scalar field…

General Relativity and Quantum Cosmology · Physics 2015-12-02 Shin'ichi Nojiri , S. D. Odintsov , V. K. Oikonomou , Emmanuel N. Saridakis

The dynamics of a minimally coupled scalar field in the expanding universe is discussed with special reference to phantom cosmology. The evolution of the universe with a phantom field vis-a-vis a quintessence field is compared. Phantom…

Astrophysics · Physics 2009-11-10 Vinod B. Johri

A refined version of a recently introduced method for analysing the dynamics of an inhomogeneous irrotational dust universe is presented. A fully non-perturbative numerical computation of the time dependence of volume in this framework…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-01 Harald Skarke

We disclose the thermodynamical properties of the apparent horizon in a nonsingular universe. We take into account the zero-point length correction to the gravitational potential and derive the modified entropy expression that includes…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Ahmad Sheykhi , Leila Liravi , Kimet Jusufi

We propose that the Universe created from "nothing" with relatively small particles number and quickly relaxed to quasiequilibrium state at the Planck parameters. The classic cosmological solution for this Universe with Lambda-term has two…

General Relativity and Quantum Cosmology · Physics 2009-12-30 V. Burdyuzha , O. Lalakulich , Yu. Ponomarev , G. Vereshkov

Recently, the cosmological deceleration-acceleration transition redshift in $f(R)$ gravity has been considered in order to address consistently the problem of cosmic evolution. It is possible to show that the deceleration parameter changes…

General Relativity and Quantum Cosmology · Physics 2016-04-27 Alireza Sepehri , Salvatore Capozziello , Mohammad Reza Setare

Unlike crushing singularities, the so-called Type IV finite-time singularity offers the possibility that the Universe passes smoothly through it, without any catastrophic effects. Then the question is if the effects of a Type IV singularity…

General Relativity and Quantum Cosmology · Physics 2015-12-23 S. D. Odintsov , V. K. Oikonomou