50 research outputs found
Threefold extremal contractions of types (IC) and (IIB)
Let be a germ of a threefold with terminal singularities along an
irreducible reduced complete curve with a contraction
such that and is ample. Assume that contains
a point of type (IC) or (IIB). We complete the classification of such germs in
terms of a general member containing .Comment: 22 pages, LaTe
Threefold extremal contractions of type IA
Let be a germ of a threefold with terminal singularities along an
irreducible reduced complete curve with a contraction
such that C=f^{-1}(o)_{\red} and is ample. Assume that a general
member meets only at one point and furthermore is
Du Val of type A if index. We classify all such germs in terms of a
general member containing .Comment: LaTeX, 37 page
Threefold extremal contractions of type (IIA), II
Let be a germ of a threefold with terminal singularities along
an irreducible reduced complete curve with a contraction such that and is ample. Assume that
contains a point of type (IIA). This paper continues our study of such germs
containing a point of type (IIA) started in our previous paper
arXiv:1601.07671.Comment: 27 pages, LaTeX, to appear in Nigel Hitchin 70 Conference Proceeding