Interacting Tachyonic Scalar Field III

Abstract

This study explores the plausibility of an interacting tachyonic scalar, homogeneous in nature, as a promising candidate for dynamic dark energy, offering insights into the observed accelerated expansion of the universe. The parameterization of the interaction between the tachyonic field, matter, and Hubble's parameter is performed linearly. The analysis focuses on fundamental cosmological parameters in a flat universe $(K = 0)$: expansion rate, universe age, energy density evolution for matter and the tachyonic field. The study also examines the coupling strength between the tachyonic field and matter, revealing a maximum value of unity when the interaction depends solely on their energy densities. Combining them also yields an upper limit of unity (precisely 0.7) for the coupling strength.