Minimal models of canonical 3-fold singularities and their Betti numbers
نویسنده
چکیده
Let (X,x) be a germ of an isolated canonical 3-fold singularity. Fix a representative X of the germ which is Stein and contractible. Let φ′ : Y ′ → X be a crepant projective morphism from Y ′ with terminal Q-factorial singularities, and ψ : Y → Y ′ an analytic Q-factorialisation of Y ′ at its singular points. The aim of this paper is to calculate the Betti numbers of Y or, equivalently, the intersection cohomology Betti numbers of Y ′.
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