On the Uniqueness of a Gorenstein Model of a Del Pezzo Fibration over P
نویسنده
چکیده
We prove the following statement (theorem 2.1). Let V/P be a birationally rigid Gorenstein Mori fibration on del Pezzo surfaces. If a Mori fibration W is birational to V , then either they are isomorphic, or W is non-Gorenstein. The result was obtained during my stay at the Max-Planck-Institut für Mathematik in Bonn. I would like to use this opportunity and thank the Directors and the staff of the Institute for hospitality.
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