Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model

Sharif, M.; Saleem, Rabia

doi:10.1088/1475-7516/2014/12/038

Title: Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model

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Abstract

This paper is devoted to study the effects of bulk viscous pressure on an inflationary generalized cosmic Chaplygin gas model using FRW background. The matter contents of the universe are assumed to be inflaton and imperfect fluid. We evaluate inflaton fields, potentials and entropy density for variable as well as constant dissipation and bulk viscous coefficients in weak as well as high dissipative regimes during intermediate era. In order to discuss inflationary perturbations, we evaluate entropy density, scalar (tensor) power spectra, their corresponding spectral indices, tensor-scalar ratio and running of spectral index in terms of inflaton which are constrained using recent Planck, WMAP7 and Bicep2 probes.

Authors:

Sharif, M.; Saleem, Rabia ^[1]

Department of Mathematics, University of the Punjab, Quaid-e-Azam Campus, Lahore-54590 (Pakistan)

Publication Date:: Mon Dec 01 00:00:00 EST 2014

OSTI Identifier:: 22382067

Resource Type:: Journal Article

Journal Name:: Journal of Cosmology and Astroparticle Physics

Additional Journal Information:: Journal Volume: 2014; Journal Issue: 12; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516

Country of Publication:: United States

Language:: English

Subject:: 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; ENTROPY; FLUIDS; MATTER; PERTURBATION THEORY; POTENTIALS; PROBES; SCALARS; SPECTRA; TENSORS; UNIVERSE

Citation Formats


                    Sharif, M., and Saleem, Rabia. Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model.  United States: N. p., 2014. 
        Web.  doi:10.1088/1475-7516/2014/12/038.

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                    Sharif, M., & Saleem, Rabia. Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model.  United States.  https://doi.org/10.1088/1475-7516/2014/12/038

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                    Sharif, M., and Saleem, Rabia. 2014.  
        "Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model".  United States.  https://doi.org/10.1088/1475-7516/2014/12/038.

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@article{osti_22382067,

  title        = {Effects of viscous pressure on warm inflationary generalized cosmic Chaplygin gas model},

  author       = {Sharif, M. and Saleem, Rabia},

  abstractNote = {This paper is devoted to study the effects of bulk viscous pressure on an inflationary generalized cosmic Chaplygin gas model using FRW background. The matter contents of the universe are assumed to be inflaton and imperfect fluid. We evaluate inflaton fields, potentials and entropy density for variable as well as constant dissipation and bulk viscous coefficients in weak as well as high dissipative regimes during intermediate era. In order to discuss inflationary perturbations, we evaluate entropy density, scalar (tensor) power spectra, their corresponding spectral indices, tensor-scalar ratio and running of spectral index in terms of inflaton which are constrained using recent Planck, WMAP7 and Bicep2 probes.},

  doi          = {10.1088/1475-7516/2014/12/038},

  url          = {https://www.osti.gov/biblio/22382067},
  journal      = {Journal of Cosmology and Astroparticle Physics},

  issn         = {1475-7516},

  number       = 12,

  volume       = 2014,

  place        = {United States},

  year         = {Mon Dec 01 00:00:00 EST 2014},

  month        = {Mon Dec 01 00:00:00 EST 2014}

}

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