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arXiv · 1702.04720

Dynamics of coupled phantom and tachyon fields

M. Shahalam·S. D. Pathak·Shiyuan Li·R. Myrzakulov·Anzhong Wang
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Abstract

In this paper, we apply the dynamical analysis to a coupled phantom field with scaling potential taking particular forms of the coupling (linear and combination of linear), and present phase space analysis. We investigate if there exist late time accelerated scaling attractor that has the ratio of dark energy and dark matter densities of the order one. We observe that the scrutinized couplings cannot alleviate the coincidence problem, however acquire stable late time accelerated solutions. We also discuss coupled tachyon field with inverse square potential assuming linear coupling.

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M. Shahalam, S. D. Pathak, Shiyuan Li, R. Myrzakulov, Anzhong Wang. 2017-10-23. Dynamics of coupled phantom and tachyon fields. https://doi.org/10.1140/epjc%2Fs10052-017-5255-1

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