Birational geometry and deformations of nilpotent orbits
نویسنده
چکیده
In order to explain what we want to do in this paper, let us begin with an explicit example. Let O be the nilpotent orbit of sl(4,C) with Jordan type [3, 1] (under the adjoint action of G := SL(4,C)). We will denote by Xi,j,k the cotangent bundle T (G/Pi,j,k) of the projective manifold G/Pi,j,k where Pi,j,k is a parabolic subgroup of G with flag type (i, j, k). Then the closure Ō of O admits three different Springer resolutions
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