A tachyonic scalar field with mutually interacting components

Murli Manohar Verma; Shankar Dayal Pathak

doi:10.1007/s10773-012-1116-8

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arXiv · 1112.2559

A tachyonic scalar field with mutually interacting components

Murli Manohar Verma·Shankar Dayal Pathak

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Abstract

We investigate the tachyonic cosmological potential $V(ϕ)$ in two different cases of the quasi-exponential expansion of universe and discuss various forms of interaction between the two components---matter and the cosmological constant--- of the tachyonic scalar field, which leads to the viable solutions of their respective energy densities. The distinction among the interaction forms is shown to appear in the $O_{m}(x)$ diagnostic. Further, the role of the high- and low-redshift observations of the Hubble parameter is discussed to determine the proportionality constants and hence the correct form of matter--cosmological constant interaction.

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Murli Manohar Verma, Shankar Dayal Pathak. 2011-12-09. A tachyonic scalar field with mutually interacting components. https://doi.org/10.1007/s10773-012-1116-8

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