Supposons que le lieu critique Σ dʼune fonction analytique complexe f sur un espace affine soit un espace avec un point singulier isolé à lʼorigine 0, et que le nombre de Milnor de la fonction f restreinte à des sections transverses à soit constant. Alors, la théorie générale des faisceaux pervers impose des conditions strictes sur la cohomologie de la fibre de Milnor de f en 0 et, de façon encore plus surprenante, des restrictions sur la cohomologie de la fibre de Milnor dʼune section hyperplane générique.
Suppose that the critical locus Σ of a complex analytic function f on affine space is, itself, a space with an isolated singular point at the origin 0, and that the Milnor number of f restricted to normal slices of is constant. Then, the general theory of perverse sheaves puts severe restrictions on the cohomology of the Milnor fiber of f at 0, and even more surprising restrictions on the cohomology of the Milnor fiber of generic hyperplane slices.
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@article{CRMATH_2012__350_3-4_217_0, author = {L\^e, D\~{u}ng Tr\'ang and Massey, David B.}, title = {A remark on vanishing cycles with two strata}, journal = {Comptes Rendus. Math\'ematique}, pages = {217--220}, publisher = {Elsevier}, volume = {350}, number = {3-4}, year = {2012}, doi = {10.1016/j.crma.2012.01.008}, language = {en}, url = {http://www.numdam.org/articles/10.1016/j.crma.2012.01.008/} }
TY - JOUR AU - Lê, Dũng Tráng AU - Massey, David B. TI - A remark on vanishing cycles with two strata JO - Comptes Rendus. Mathématique PY - 2012 SP - 217 EP - 220 VL - 350 IS - 3-4 PB - Elsevier UR - http://www.numdam.org/articles/10.1016/j.crma.2012.01.008/ DO - 10.1016/j.crma.2012.01.008 LA - en ID - CRMATH_2012__350_3-4_217_0 ER -
%0 Journal Article %A Lê, Dũng Tráng %A Massey, David B. %T A remark on vanishing cycles with two strata %J Comptes Rendus. Mathématique %D 2012 %P 217-220 %V 350 %N 3-4 %I Elsevier %U http://www.numdam.org/articles/10.1016/j.crma.2012.01.008/ %R 10.1016/j.crma.2012.01.008 %G en %F CRMATH_2012__350_3-4_217_0
Lê, Dũng Tráng; Massey, David B. A remark on vanishing cycles with two strata. Comptes Rendus. Mathématique, Tome 350 (2012) no. 3-4, pp. 217-220. doi : 10.1016/j.crma.2012.01.008. http://www.numdam.org/articles/10.1016/j.crma.2012.01.008/
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