Level-rank duality of untwisted and twisted D-branes of the image WZW model Original Research Article

We analyze the level-rank duality of untwisted and ε-twisted D-branes of the image WZW model. Untwisted D-branes of image are characterized by integrable tensor and spinor representations of image. Level-rank duality maps untwisted image D-branes corresponding to (equivalence classes of ) tensor representations onto those of image. The ε-twisted D-branes of image are characterized by (a subset of ) integrable tensor and spinor representations of image. Level-rank duality maps spinor ε-twisted image D-branes onto those of image. For both untwisted and ε-twisted D-branes, we prove that the spectrum of an open string ending on these D-branes is isomorphic to the spectrum of an open string ending on the level-rank-dual D-branes.