Derivation algebras of toric varieties
نویسندگان
چکیده
Normal affine algebraic varieties in characteristic 0 are uniquely determined (up to isomorphism) by the Lie algebra of derivations of their coordinate ring. This was shown by Siebert [Si] and, independently, by Hauser and the third author [HM]. In both papers the assumption of normality is essential. There are nonisomorphic non-normal varieties with isomorphic Lie algebras. The third author [M] treated certain non-normal varieties defined in combinatorial terms by showing that closed simplicial complexes can be reconstructed from the Lie algebra of their Stanley-Reisner ring. Here we study this problem for (in general, nonnormal) toric varieties defined by simplicial affine semigroups.
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