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arXiv · 2107.04780

Viscous interacting and stability on dark matter Bose-Einstein condensation with modified Chaplygin gas

E. Mahichi·Alireza Amani·M. A. Ramzanpour
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Abstract

In this paper, the viscous cosmological dynamics are studied in the presence of dark matter Bose-Einstein Condensation (BEC) by curved-FRW background. For this purpose, we use the BEC regime rather than the normal dark matter (the cold dark matter or the barotropic dark matter) with the dark matter Equation of State (EoS) as $p_{dm} \propto ρ_{dm}^2$, which arises from the gravitational form. Therefore, we obtain the corresponding continuity equations with the existence of the universe components by considering an interacting model with modified Chaplygin gas. Afterward, we derive the energy density and the pressure of dark energy in terms of the redshift parameter. And then, by introducing a parametrization function and fitting it with 51 supernova data with the likelihood analysis, we find the cosmological parameters versus redshift parameter. In what follows, we plot the corresponding dynamic graphs proportional to redshift, and then we represent the universe is currently undergoing an accelerated expansion phase. Finally, we explore the stability and the instability of the present model with the sound speed parameter.

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E. Mahichi, Alireza Amani, M. A. Ramzanpour. 2021-07-10. Viscous interacting and stability on dark matter Bose-Einstein condensation with modified Chaplygin gas. https://doi.org/10.1139/cjp-2021-0111

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