Generalized Chaplygin Gas and Varying Bulk Viscosity in Lyra Geometry

Authors: A. K. Sethi, R. N. Patra, B. Nayak

Abstract:

In this paper, we have considered Friedmann-Robertson-Walker (FRW) metric with generalized Chaplygin gas which has viscosity in the context of Lyra geometry. The viscosity is considered in two different ways (i.e. zero viscosity, non-constant r (rho)-dependent bulk viscosity) using constant deceleration parameter which concluded that, for a special case, the viscous generalized Chaplygin gas reduces to modified Chaplygin gas. The represented model indicates on the presence of Chaplygin gas in the Universe. Observational constraints are applied and discussed on the physical and geometrical nature of the Universe.

Keywords: Bulk viscosity, Lyra geometry, generalized Chaplygin gas, cosmology.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.3593134

References:

[1] Perlmutter, S., et al., The Astrophysical Journal, 517, 565-586.doi:10.1086/307221, (1999).
[2] Riess, A.G., et al. (1998), The Astrophysical Journal, 116, 1009-1038. doi:10.1086/300499.
[3] Hawkins, E. et al.: Mon. Not. Roy. Astron. Soc. 346(2003) 78; Tegmark, M. et al.: Phys. Rev. D69(2004)103501; Cole, S.et al.: Mon. Not. Roy. Astron. Soc. 362(2005)505.
[4] R. R. Caldwell, Phys. Lett. B 545 (2002) 23, http://dx.doi.org/10.1016/S0370-2693(02)02589-3.
[5] M. R. Setare, J. Sadeghi, A. R. Amani, Phys. Lett. B673 (2009) 241.
[6] M. R. Setare, Phys. Lett. B 642 (2006)1.
[7] N. Afshordi, D. J. H. Chung, and G. Geshnizjani, Phys. Rev. D 75 (2007) 083513.
[8] Y. Wang, D. Wands, L. Xu, J. De-Santiago, A. Hojjati, Phys. Rev. D 87 (2013) 083503.
[9] M. R. Setare, Phys. Lett. B648 (2007) 329.
[10] M. R. Setare, Int. J. Mod. Phys. D18 (2009)419.
[11] U. Debnath, A. Banerjee, and S. Chakraborty, Class. Quantum Grav. 21 (2004) 5609.
[12] Xiang-Hua Zhai et al. “Viscous Generalized Chaplygin Gas”, (arxiv: astro-ph/0511814).
[13] Saadat, H., Pourhassan, B., Astrophys. Space Sci. (2012). doi:10.1007/s10509-012-1268-2.
[14] Brevik, I: Grav. Cosmol. 14(2008)332.
[15] Gorbunova, O. and Sebastiani, L.: Gen. Relativ. Gravit. 42(2010)2873.
[16] Chaubey, R. (2009), Astrophysics and Space Science, 321, 241-246. doi:10.1007/s10509-009-0027-5.
[17] Chaubey, R. (2011), Natural Science, 3, 513-516. doi: 10.4236/ns.2011.37072.
[18] Saadat, H. & Pourhassan,B. Int J Theor Phys (2013) 52: 3712. https://doi.org/10.1007/s10773-013-1676-2.
[19] Baffou,E.H, Salako,I.G & Houndjo,M.J.S,. International Journal of Geometric Methods in Modern Physics, Vol. 14, No. 04, 1750051 (2017). https://doi.org/10.1142/S0219887817500517.
[20] Lyra, G, (1951) Math, Z 54,52.
[21] D.K.sen, Phys. Z, Vol.149, pp.311-323, (1957).