Phantom cosmology with a nonlinear Born-Infeld type scalar field

摘要

Recent many physicists suggest that the dark energy in the universe might result from the Born-Infeld (B-I) type scalar field of string theory. The universe of B-I type scalar field with potential can undergo a phase of accelerating expansion. The corresponding equation of state parameter lies in the range of -1 < omega < -1/3. The equation of state parameter of B-I type scalar field without potential lies in the range of 0 <= omega <= 1. We find that weak energy condition and strong energy condition are violated for phantom B-I type scalar field. The equation of state parameter lies in the range of omega < -1.