D-branes on Noncommutative Orbifolds

TL;DR

This paper investigates tachyon condensation on noncommutative toric orbifolds with a Z2 symmetry, revealing how anti-branes naturally emerge and analyzing unstable bound states, especially for irrational B-field values.

Contribution

It demonstrates the natural incorporation of anti-branes via Z2 symmetry and compares results with quantum torus approaches, focusing on irrational noncommutative orbifolds.

Findings

Anti-branes are naturally incorporated through Z2 symmetry.

Equivalent results to quantum torus approaches are obtained.

Unstable bound states are characterized for irrational B-field values.

Abstract

We study tachyon condensation on noncommutative toric orbifolds with a $Z_2$ discrete group and explore the various kins of brane bound states arising in the case of irrational values of the B-field. We show that $Z_$ 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-barD 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.