Relative Multiplicities of Graded Algebras
نویسنده
چکیده
Without any finiteness assumption, we define a sequence of relative multiplicities for a pair A ⊂ B of standard graded Noetherian algebras that extends the notion of relative multiplicities of Simis, Ulrich and Vasconcelos and unifies them with the j-multiplicity of ideals introduced by Achilles and Manaresi as well as the j-multiplicity of modules defined by Ulrich and Validashti. Using our relative multiplicities, we give numerical criteria for integrality and birationality of the extension A⊂ B.
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تاریخ انتشار 2012