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Jet schemes, log discrepancies and Inversion of Adjunction

Lawrence Ein·Mircea Mustata·Takehiko Yasuda
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Abstract

We use the theory of motivic integration for singular spaces to give a characterization of minimal log discrepencies in terms of the codimension of certain subsets of spaces of arcs. This is done for arbitrary pairs $(X,Y)$, with $X$ normal and Q-Gorenstein. As a first application, we prove a precise version of Inversion of Adjunction, in the case when the ambient variety is smooth. Another application concerns the semicontinuity of minimal log discrepancies on smooth varieties.

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Lawrence Ein, Mircea Mustata, Takehiko Yasuda. 2003-02-22. Jet schemes, log discrepancies and Inversion of Adjunction. https://doi.org/10.1007/s00222-003-0298-3

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