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Related papers: Emergent Universe and Phantom Tachyon Model

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Emergent scenario of cosmic evolution is a topic of great interest in recent cosmology, especially because it describes a non-singular origin of the Universe unlike the Big-Bang models. This types of cosmic evolution pattern have already…

General Relativity and Quantum Cosmology · Physics 2023-09-01 Subhayan Maity , Sujayita Bakra

In this letter, we have considered the universe is filled with the mixture of tachyonic field and scalar or phantom field. If the tachyonic field interacts with scalar or phantom field, the interaction term decays with time and the energy…

General Relativity and Quantum Cosmology · Physics 2009-04-24 Surajit Chattopadhyay , Ujjal Debnath

We investigate the Einstein static universe (ESU) and the emergent universe scenario in the framework of Ho\v{r}ava-Lifshitz-like $F(R)$ gravity. We first perform a dynamical analysis in the phase space, and amongst others we show that a…

General Relativity and Quantum Cosmology · Physics 2016-06-10 M. Khodadi , Y. Heydarzade , F. Darabi , E. N. Saridakis

We apply a very simple procedure to construct non-singular cosmological models for flat Friedmann universes filled with minimally coupled scalar fields or by tachyon Born-Infeld-type fields. Remarkably, for the minimally coupled scalar…

General Relativity and Quantum Cosmology · Physics 2024-03-14 Alexander Kamenshchik , Polina Petriakova

The possibility of explanation of accelerated expansion of the Universe by tachyonic scalar fields which homogeneously fill the world is discussed. The dependences of potential and kinetic term on scale factor are deduced for the case of…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-14 Bohdan Novosyadlyj

The possibility of an emergent universe solution to Einstein's field equations allowing for an irreversible creation of matter at the expense of the gravitational field is shown. With the universe being chosen as spatially flat FRW…

General Relativity and Quantum Cosmology · Physics 2016-09-27 Sunandan Gangopadhyay , Anirban Saha , S. Mukherjee

The cosmological effects of the tachyon rolling down to its ground state are discussed by coupling a simple effective field theory for the tachyon field to Einstein gravity. As the tachyon rolls down to the minimum of its potential the…

High Energy Physics - Theory · Physics 2009-10-07 G. W. Gibbons

A general framework for an emergent universe scenario has been given which makes use of an equation of state. The general features of the model have also been studied and possible primordial composition of the universe have been suggested.

General Relativity and Quantum Cosmology · Physics 2009-11-11 S. Mukherjee , B. C. Paul , N. K. Dadhich , S. D. Maharaj , A. Beesham

A model of an emergent universe is formulated using the mechanism of particle creation. Here the universe is considered as a non-equilibrium thermodynamical system with dissipation due to particle creation mechanism. The universe is chosen…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Subenoy Chakraborty

The emergent scenario provides a possible way to avoid the big bang singularity by assuming that the universe originates from an Einstein static state. Therefore, an Einstein static universe stable under perturbations is crucial to a…

General Relativity and Quantum Cosmology · Physics 2022-02-10 Qihong Huang , Bing Xu , He Huang , Feiquan Tu , Ruanjing Zhang

The emergent universe provides a possible method to avoid the big bang singularity by considering that the universe stems from an stable Einstein static universe rather than the singularity. Since the Einstein static universe exists before…

General Relativity and Quantum Cosmology · Physics 2023-05-11 Qihong Huang , Kaituo Zhang , He Huang , Bing Xu , Feiquan Tu

In this paper, we have considered the curved universe which is filled by tachyonic field. We have found the exact solutions for the field, pressure, density, and scale factor and some cosmological parameters. In such universe, we have…

General Relativity and Quantum Cosmology · Physics 2009-02-19 J. Sadeghi , A. R. Amani

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

In this work we study an alternative scheme for an Emergent Universe scenario in the context of a Jordan-Brans-Dicke theory, where the universe is initially in a truly static state supported by a scalar field located in a false vacuum. The…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Pedro Labrana , Hobby Cossio

We discuss the expansion of the universe in the FRLW model assuming that the source of dark energy is either tachyonic scalar field or quintessence. The tachyonic scalar field with exponential and power-law potential (function of…

General Relativity and Quantum Cosmology · Physics 2015-08-11 Murli Manohar Verma , Shankar Dayal Pathak

In this work we study the cosmological evolution of a dark energy model with two scalar fields, i.e. the tachyon and the phantom tachyon. This model enables the equation of state $w$ to change from $w>-1$ to $w<-1$ in the evolution of the…

Astrophysics · Physics 2009-12-04 Shang-Gang Shi , Yun-Song Piao , Cong-Feng Qiao

We study cosmological effects of homogeneous tachyon field as dark energy. We concentrate on two different scalar field potentials, the inverse square potential and the exponential potential. These models have a unique feature that the…

Astrophysics · Physics 2008-11-26 H. K. Jassal

An inflationary universe scenario in the context of tachyon field is studied. This study is done from an ansantz for the effective potential of cosmological perturbations $U(\eta)$. We describe in great detail the analytical solutions of…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Ramon Herrera , Roberto G. Perez

We study the emergent scenario, which is proposed to avoid the big bang singularity, in the Einstein-Cartan (EC) theory with a positive cosmological constant and a perfect fluid by analyzing the existence and stability of the Einstein…

General Relativity and Quantum Cosmology · Physics 2015-10-19 Qihong Huang , Puxun Wu , Hongwei Yu

We study the possibility to construct an observationally viable scenario where both early Inflation and the recently detected accelerated expansion of the universe can be explained by using a single scalar field associated with the Tachyon.…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Victor H. Cardenas