Topological Defects in String Theory Orbifolds with Target Spaces C/Zn and S1/Z2

Abstract

We study conformal defects in two important examples of string theory orbifolds. First, we show that topological defects in the language of Landau-Ginzburg models carry information about the RG flow between the non-compact orbifolds C/Zd. Such defects are shown to correctly implement the bulk-induced RG flow on the boundary. Secondly, we study what the possible conformal defects are between the c = 1 bosonic 2D conformal field theories with target space S^=Z2. The defects cataloged here are obtained from boundary states corresponding to D-branes in the c = 2 free theory with target space S^/Z2 x S^=Z2. Via the unfolding procedure, such boundary states are later mapped to defects between the circle orbifolds. Furthermore, we compute the algebra of the topological class of defects at different radii.