  We present the study of the dynamics of the geometrical tachyon field on an
unstable D3-brane in the background of a bulk tachyon field of a D3-brane
solution of Type-0 string theory. We find that the geometrical tachyon
potential is modified by a function of the bulk tachyon and inflation occurs at
weak string coupling, where the bulk tachyon condenses, near the top of the
geometrical tachyon potential. We also find a late accelerating phase when the
bulk tachyon asymptotes to zero and the geometrical tachyon field reaches the
minimum of the potential.
