A tachyonic scalar field with mutually interacting components

We investigate the tachyonic cosmological potential $V(\phi)$ 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.Comment: 14 page

Nonsingular Bouncing Model in Closed and Open Universe

We investigate the background dynamics of a class of models with noncanonical scalar field and matter both in Friedmann Lemaitre Robertson Walker (FLRW) closed and open spacetime. The detailed dynamical system analysis is carried out in a bouncing scenario. Cosmological solutions satisfying the stability and bouncing conditions are obtained using the tools of the dynamical system