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Cotangent cohomology of rational surface singularities

Klaus Altmann·Jan Stevens
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Abstract

We show that the number of generators of the n-th cotangent cohomology group (n >=2) is the same for all rational surface singularities Y. For a large class of rational surface singularities, including quotient singularities, this number is also the dimension. For them we obtain an explicit formula for the corresponding Poincare series.

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Klaus Altmann, Jan Stevens. 1998-09-23. Cotangent cohomology of rational surface singularities. https://doi.org/10.1007/s002220050345

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