Small Bound for Birational Automorphism Groups of Algebraic Varieties (with an Appendix by Yujiro Kawamata)
نویسنده
چکیده
We give an effective upper bound of |Bir(X)| for the birational automorphism group of an irregular n-fold (with n = 3) of general type in terms of the volume V = V (X) under an ”albanese smoothness and simplicity” condition. To be precise, |Bir(X)| ≤ d3V . An optimum linear bound |Bir(X)| ≤ 1 3 ×42V is obtained for those 3-folds with non-maximal albanese dimension. For all n ≥ 3, a bound |Bir(X)| ≤ dnV 10 is obtained when albX is generically finite, alb(X) is smooth and Alb(X) is simple.
منابع مشابه
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