TACHYON FIELD-INSPIRED DARK ENERGY AND SUPERNOVAE CONSTRAINTS

The tachyon field in cosmology is studied in this paper by applying the generating function method to obtain exact solutions. The equation of state parameter of the tachyon field is , which can be expressed as a function in terms of the redshift z. Based on these solutions, we propose some tachyon-inspired dark energy models to explore the properties of the corresponding cosmological evolution. The explicit relations between the Hubble parameter and redshift enable us to test the models with SNeIa data sets easily. In this paper, we employ the SNeIa data with the parameter measured from the SDSS and the shift parameter from WMAP observations to constrain the parameters in our models.