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arXiv · 2012.13429

A multifield tachyon quintom model of dark energy and fate of the universe

Muhammad Zahid Mughal·Iftikhar Ahmad
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Abstract

We investigate a multi-field model of dark energy in this paper. We develop a model of dark energy with two multiple scalar fields, one we consider, is a multifield tachyon and the other is multi-field phantom tachyon scalars. We make an analysis of the system in phase space by considering inverse square potentials suitable for these models. Through the development of an autonomous dynamical system, the critical points and their stability analysis is performed. It has been observed that these stable critical points are satisfied by power law solutions. Moving on towards the analysis we can predict the fate of the universe. A special feature of this model is that it affects the equation of state parameter w to alter from being it greater than negative one to be less than it during the evolutionary phase of the universe. Thus, its all about the phantom divide which turns out to be decisive in the evolution of the cosmos in these models.

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Muhammad Zahid Mughal, Iftikhar Ahmad. 2020-12-24. A multifield tachyon quintom model of dark energy and fate of the universe. https://arxiv.org/abs/2012.13429

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