On a Theorem of Greuel and Steenbrink
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A famous theorem of Greuel and Steenbrink states that the first Betti number of the Milnor fibre of a smoothing of a normal surface singularity vanishes. In this paper we prove a general theorem on the first Betti number of a smoothing that implies an analogous result for weakly normal singularities.
KeywordsSingularities Topology of smoothings Weakly normal spaces
2010Mathematics Subject Classification:14B07 32S25 32S30
The basis of the above text is part of my PhD thesis , but the results were never properly published. For this version only minor cosmetic changes have been made. I thank D. Siersma for asking me about the result and the idea of writing it up as a contribution to the volume on occasion of Gert-Martins 70th birthday.
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