The relationship between skew group algebras and orbifold theory
نویسنده
چکیده
Let V be a simple vertex operator algebra and let G be a finite automorphism group of V . In [DY], it was shown that any irreducible V -module is a completely reducible V module where V G is the G-invariant sub-vertex operator algebra of V . In this paper, we give an alternative proof of this fact using the theory of skew group algebras. We also extend this result to any irreducible g-twisted V -module when g is in the center of G and V is a g-rational vertex operator algebra.
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