LANDAU-GINZBURG ORBIFOLDS WITH DISCRETE TORSION

We complete the classification of (2,2) vacua that can be constructed from Landau-Ginzburg models by Abelian twists with arbitrary discrete torsions. Compared to the case without torsion, the number of new spec tra is surprisingly small. In contrast to a popular expectation mirror symmetry does not seem to be related to discrete torsion (at least no t in the present compactification framework). The Berglund-Hubsch cons truction naturally extends to orbifolds with torsion; for more general potentials, on the other hand, the new spectra neither have nor provi de mirror partners in our class of models.