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arXiv · 1012.1445

Dynamics of Logamediate and Intermediate Scenarios in the Dark Energy Filled Universe

Piyali Bagchi Khatua·Ujjal Debnath
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Abstract

We have considered a model of two component mixture i.e., mixture of Chaplygin gas and barotropic fluid with tachyonic field. In the case, when they have no interaction then both of them retain their own properties. Let us consider an energy flow between barotropic and tachyonic fluids. In both the cases we find the exact solutions for the tachyonic field and the tachyonic potential and show that the tachyonic potential follows the asymptotic behavior. We have considered an interaction between these two fluids by introducing a coupling term. Finally, we have considered a model of three component mixture i.e., mixture of tachyonic field, Chaplygin gas and barotropic fluid with or without interaction. The coupling functions decays with time indicating a strong energy flow at the initial period and weak stable interaction at later stage. To keep the observational support of recent acceleration we have considered two particular forms (i) Logamediate Scenario and (ii) Intermediate Scenario, of evolution of the Universe. We have examined the natures of the recent developed statefinder parameters and slow-roll parameters in both scenarios with and without interactions in whole evolution of the universe.

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Piyali Bagchi Khatua, Ujjal Debnath. 2010-12-07. Dynamics of Logamediate and Intermediate Scenarios in the Dark Energy Filled Universe. https://doi.org/10.1007/s10773-010-0617-6

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