Dynamical system analysis of Dirac-Born-Infeld scalar field cosmology in coincident f(Q) gravity*

Abstract

In this article, we present a dynamical system analysis of a Dirac-Born-Infeld scalar field in a modified gravity context. We considered a polynomial form of modified gravity, used two different types of scalar potential, polynomial and exponential, and found a closed autonomous dynamical system of equations. We analyzed the fixed points of such a system and evaluated the conditions under which deceleration to late-time acceleration occurs in this model. We note the similarity of the two models and show that our result is consistent with a previous study on Einstein's gravity. We also investigated the phenomenological implications of our models by plotting EoS (ω), energy density (Ω), and deceleration parameter (q) w.r.t. to e-fold time and comparing to the present value. We conclude the paper by observing how the dynamical system analysis differs in the modified gravity, and present the future scope of our research.