D-branes on noncommutative orbifolds

Abstract

We study tachyon condensation on noncommutative toric orbifolds with a 2 discrete group and explore the various kinds of brane bound states arising in the case of irrational values of the B-field. We show that 2 symmetry of the orbifolds incorporates naturally anti-branes in the spectrum and leads to equivalent results as those obtained by starting from an original pair of D- system on quantum torii. A specific analysis is deserved to the irrational representation of NC orbifolds and to the unstable bound states generated by the condensation.