New cosmological solutions from soliton transform technique

In this talk, a brief introduction to string cosmology is given in the begi nning. We recall duality symmetries and the main ingredients of pre-big ban g scenario in the context of string theory. One of the interesting aspects of stringy T-duality symmetry is the possibility of generating new cosmolog ical solution starting from a known solution of the string effective action . In the later part of the talk, we apply the soliton transformation techni que, in the string cosmological context, to obtain new background solutions . These backgrounds satisfy the equations of motion by construction.