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arXiv · 2412.20118

Kinetic coupled tachyon: A dynamical system analysis

Francesco Pace·Alberto Rozas-Fernández·Özgen Tunç Türker
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Abstract

We present and examine a kinetically coupled tachyon dark energy model, where a tachyon scalar field interacts with the matter sector. More specifically, we deduce this cosmological setting from a generalised interacting dark energy model that allows for the kinetic term of the scalar field to couple to the matter species a priori in the action. A thorough dynamical system analysis and its cosmological implications unveil the appearance of a scaling solution which is also an attractor of the system, thanks to a novel critical point, with a period of accelerated expansion thereafter. This new solution, not present in the uncoupled case, has the enticing consequence of alleviating the coincidence problem.

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Francesco Pace, Alberto Rozas-Fernández, Özgen Tunç Türker. 2024-12-28. Kinetic coupled tachyon: A dynamical system analysis. https://doi.org/10.1016/j.dark.2024.101786

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