English
Related papers

Related papers: Finite time pseudo-rip singularity in cosmology

200 papers

A cosmological model of a flat Friedmann universe filled with a mixture of anti-Chaplygin gas and dust-like matter exhibits a future soft singularity, where the pressure of the anti-Chaplygin gas diverges (while its energy density is…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Zoltán Keresztes , László Á. Gergely , Alexander Yu. Kamenshchik

In this paper, we explore the conformal structure of singularities arising from varying fundamental constants using the method of Penrose diagrams. We employ a specific type of bimetric model featuring two different metrics. One metric…

General Relativity and Quantum Cosmology · Physics 2024-09-17 Konrad Marosek , Adam Balcerzak

We analyse the emergent cosmological dynamics corresponding to the mean field hydrodynamics of quantum gravity condensates, in the tensorial group field theory formalism. We focus in particular on the cosmological effects of fundamental…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Daniele Oriti , Xiankai Pang

In this paper we present two concrete models of non-perfect fluid with bulk viscosity to interpret the observed cosmic accelerating expansion phenomena, avoiding the introduction of exotic dark energy. The first model we inspect has a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Xin-he Meng , Zhi-yuan Ma

In this paper, we attempt to explore the possibility of a obtaining a viable emergent universe scenario supported by a type of fluid known as the extended Chaplygin gas, which extends a modification to the equation of state of the well…

General Relativity and Quantum Cosmology · Physics 2025-08-13 Rikpratik Sengupta , Anirban Chanda , B C Paul , M Kalam

Here, cosmology of the late and future universe is obtained from $f(R)$-gravity with non-linear curvature terms $R^2$ and $R^3$ ($R$ being the Ricci scalar curvature). It is different from $f(R)$-dark enrgy models, where non-linear…

General Relativity and Quantum Cosmology · Physics 2009-09-17 S. K. Srivastava

Different approaches to quantum cosmology are studied in order to deal with the future singularity avoidance problem. Our results show that these future singularities will persist but could take different forms. As an example we have…

General Relativity and Quantum Cosmology · Physics 2014-09-05 Jaume de Haro

A remarkable property of modern cosmology is that it allows for a special case of symmetry, consisting in the possibility of describing the early-time acceleration (inflation) and the late-time acceleration using the same theoretical…

General Relativity and Quantum Cosmology · Physics 2016-06-14 I. Brevik , V. V. Obukhov , A. V. Timoshkin

In order to study if the bulk viscosity may induce a big rip singularity on the flat FRW cosmologies, we investigate dissipative processes in the universe within the framework of the standard Eckart theory of relativistic irreversible…

High Energy Physics - Theory · Physics 2008-11-26 Mauricio Cataldo , Norman Cruz , Samuel Lepe

A review on spatially flat D-dimensional Friedmann-Robertson-Walker (FRW) model of the universe has been performed. Some standard parameterizations of the equation of state parameter of the Dark Energy models are proposed and the…

General Relativity and Quantum Cosmology · Physics 2019-03-26 Tanwi Bandyopadhyay , Ujjal Debnath

An explicit model of $F(R)$ gravity with realizing a crossing of the phantom divide is reconstructed. In particular, it is shown that the Big Rip singularity may appear in the reconstructed model of $F(R)$ gravity. Such a Big Rip…

High Energy Physics - Theory · Physics 2010-05-27 Kazuharu Bamba , Chao-Qiang Geng , Shin'ichi Nojiri , Sergei D. Odintsov

A flat Friedmann universe filled with a mixture of anti-Chaplygin gas and dust-like matter evolves into a future soft singularity, where despite infinite tidal forces the geodesics can be continued. In the singularity the pressure of the…

General Relativity and Quantum Cosmology · Physics 2014-12-23 A. Kamenshchik , Z. Keresztes , L. Gergely

Some phantom cosmological models without big rip singularity have been constructed in a simple extended theory of gravity. In the geometrical part of the action, a minimally coupled linear function of the Ricci Scalar and the trace of the…

General Relativity and Quantum Cosmology · Physics 2021-06-14 S. K. Tripathy , B. Mishra

We present a unified treatment of the phase space of a spatially flat homogeneous and isotropic universe dominated by a phantom field. Results on the dynamics and the late time attractors (Big Rip, de Sitter, etc.) are derived without…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Valerio Faraoni

This paper determines the existence of Noether symmetry in non-minimally coupled $f(R,T)$ gravity admitting minimal coupling with scalar field models. We consider a generalized spacetime which corresponds to different anisotropic and…

General Relativity and Quantum Cosmology · Physics 2017-04-26 M. Sharif , Iqra Nawazish

In this paper we compare outcomes of some extended phantom-like cosmologies with each other and also with $\Lambda$CDM\, and $\Lambda$DGP. We focus on the variation of the luminosity distances, the age of the universe and the deceleration…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Kourosh Nozari , Faeze Kiani

A modified Friedmann equation which arises in an extension of general relativity which accommodates a time-dependent fundamental length $L(t)$ leads to cosmological models where the scale factor diverges with an essential singularity at a…

Astrophysics · Physics 2007-05-23 Paul H. Frampton

A perfect fluid, spatially flat cosmology in a $f(T)$ model, derived from a recently proposed general Born-Infeld type theory of gravity is studied. Four dimensional cosmological solutions are obtained assuming the equation of state…

General Relativity and Quantum Cosmology · Physics 2014-12-04 Soumya Jana

We give a brief review of some aspects of inhomogeneous viscous fluids in a flat Friedmann-Robertson-Walker Universe. In general, it is pointed out that several fluid models may bring the future Universe evolution to become singular, with…

General Relativity and Quantum Cosmology · Physics 2013-11-19 R. Myrzakulov , L. Sebastiani , S. Zerbini

The Little Sibling of the Big Rip is a cosmological abrupt event predicted by some phantom cosmological models that could describe our Universe. When this event is approached the observable Universe and its expansion rate grow infinitely,…

General Relativity and Quantum Cosmology · Physics 2019-10-16 Teodor Borislavov Vasilev , Mariam Bouhmadi-López , Prado Martín-Moruno