Invariants of hypersurface singularities in positive characteristic

被引:26
作者
Boubakri, Yousra [1 ]
Greuel, Gert-Martin [1 ]
Markwig, Thomas [1 ]
机构
[1] Univ Kaiserslautern, Fachbereich Math, D-67663 Kaiserslautern, Germany
来源
REVISTA MATEMATICA COMPLUTENSE | 2012年 / 25卷 / 01期
关键词
Hypersurface singularities; Finite determinacy; Milnor number; Tjurina number; Newton non-degenerate; Inner Newton non-degenerate; CURVES;
D O I
10.1007/s13163-010-0056-1
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
We study singularities faK[[x (1),aEuro broken vertical bar,x (n) ]] over an algebraically closed field K of arbitrary characteristic with respect to right respectively contact equivalence, and we establish that the finiteness of the Milnor respectively the Tjurina number is equivalent to finite determinacy. We give improved bounds for the degree of determinacy in positive characteristic. Moreover, we consider different non-degeneracy conditions of Kouchnirenko, Wall and Beelen-Pellikaan in positive characteristic, and we show that planar Newton non-degenerate singularities satisfy Milnor's formula mu=2a <...delta-r+1. This implies the absence of wild vanishing cycles in the sense of Deligne.
引用
收藏
页码:61 / 85
页数:25
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