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Related papers: Tachyon-Chaplygin inflationary universe model

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We choose a modified Chaplygin Gas Dark energy model for considering some its cosmological behaviors. In this regards, we study different Rip singularity scenarios and bouncing model of the universe in context of this model. We show that by…

General Relativity and Quantum Cosmology · Physics 2014-01-21 S. Davood Sadatian

The early universe according to the big bang and the grand unified theories is discussed. The shortcomings of big bang are summarized together with their resolution by inflationary cosmology. Inflation, the subsequent oscillation and decay…

High Energy Physics - Phenomenology · Physics 2007-05-23 George Lazarides

We study how the initial inhomogeneities of the universe affect the onset of inflation in the closed universe. We consider the model of a chaotic inflation which is driven by a massive scalar field. In order to construct an inhomogeneous…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Osamu Iguchi , Hideki Ishihara

In this letter, I have proposed a model of variable modified Chaplygin gas and shown its role in accelerating phase of the universe. I have shown that the equation of state of this model is valid from the radiation era to quiessence model.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ujjal Debnath

This paper is devoted to the investigation of modified Chaplygin gas model in the context of solvable k-essence cosmologies. For this purpose, we construct equations of state parameter of this model for some particular values of the…

General Physics · Physics 2012-07-31 M. Sharif , K. R. Yesmakhanova , S. Rani , R. Myrzakulov

The basic workings of inflationary models are summarized, along with the arguments that strongly suggest that our universe is the product of inflation. The mechanisms that lead to eternal inflation in both new and chaotic models are…

Astrophysics · Physics 2009-10-31 Alan H. Guth

Here we generalize the results of the work of ref. [10] in modified Chaplygin gas model and tachyonic field model. Here we have studied the thermodynamical behaviour and the equation of state in terms of volume and temperature for both…

General Physics · Physics 2015-05-20 Samarpita Bhattacharya , Ujjal Debnath

We study warm-tachyon inflationary universe model in the context of the effective field theory of loop quantum cosmology. In slow-roll approximation the primordial perturbation spectrums for this model are calculated. We also obtain the…

General Physics · Physics 2015-06-22 M. R. Setare , V. Kamali

In the present paper we study warm inflationary universe models in the context of a polytropic gas. We derive the characteristics of this model in slow-roll approximation and develop our model in two cases, 1- For a constant dissipative…

General Relativity and Quantum Cosmology · Physics 2015-06-16 M. R. Setare , M. J. S. Houndjo , V. Kamali

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

An introductory account is given of the inflationary cosmology, which postulates a period of accelerated expansion during the Universe's earliest stages. The historical motivation is briefly outlined, and the modelling of the inflationary…

Astrophysics · Physics 2007-05-23 Andrew R Liddle

An introduction to solutions of the Einstein equations defining cosmological models with accelerated expansion is given. Connections between mathematical and physical issues are explored. Theorems which have been proved for solutions with…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Alan D. Rendall

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 investigate the late time acceleration with a Chaplygin type of gas in spherically symmetric inhomogeneous model. At the early phase we get Einstien-deSitter type of solution generalised to inhomogeneous spacetime. But at late stage of…

General Relativity and Quantum Cosmology · Physics 2017-02-17 D. Panigrahi , S. Chatterjee

In this article we study an intermediate inflationary model in the context of Dvali-Gabadadze-Porrati (DGP) cosmology caused by a tachyon scalar field. Considering slow-roll inflation we discuss the dynamics of the Universe. Using…

General Relativity and Quantum Cosmology · Physics 2016-06-02 A. Ravanpak , H. Farajollahi , G. F. Fadakar

We discuss chaotic inflation in the context of a phenomenological modification of gravity inspired by the Chaplygin gas equation of state. We find that all observationalconstraints can be satisfied provided the Chaplygin scale is smaller…

Astrophysics · Physics 2008-11-26 O. Bertolami , V. Duvvuri

The curvaton in an intermediate inflationary universe model is studied. This study has allowed us to find some interesting constraints on different parameters that appear in the model.

Astrophysics · Physics 2008-11-26 Sergio del Campo , Ramon Herrera

In the present work, we study warm tachyon inflation model in the context of "logamediate inflation" where the cosmological scale factor expands as $a=a_0\exp(A[\ln t]^{\lambda})$. The characteristics of this model in slow-roll…

High Energy Physics - Theory · Physics 2015-06-15 M. R. Setare , V. Kamali

Closed, singularity-free, inflationary cosmological models have recently been studied in the context of general relativity. Despite their appeal, these so called emergent models suffer from a number of limitations. These include the fact…

Astrophysics · Physics 2009-11-10 David J. Mulryne , Reza Tavakol , James E. Lidsey , George F. R. Ellis

We study a warm-tachyon inflationary model non-minimally coupled to a Gauss-Bonnet term. The general conditions required for reliability of the model are obtained by considerations of a combined hierarchy of Hubble and Gauss-Bonnet flow…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Maysam Motaharfar , Hamid Reza Sepangi
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