Abstract
We introduce the notion of logarithmic index of a vector field on a hypersurface and prove that the homological index can be expressed via the logarithmic index. Then both invariants are described in terms of logarithmic differential forms for Saito free divisors, which are hypersurfaces with nonisolated singularities, and all contracting homology groups of the complex of regular holomorphic forms on such a hypersurface are computed. In conclusion, we consider the case of normal hypersurfaces, including the case of an isolated singularity, and describe the contracting homology of the complex of regular meromorphic forms with the help of the residue of logarithmic forms.
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References
A. G. Aleksandrov, “On the de Rham complex of nonisolated singularities,” Funkts. Anal. Prilozhen., 22, No.2, 59–60 (1988).
A. G. Aleksandrov, “Nonisolated Saito singularities,” Mat. Sb. (N.S.), 137(179), No. 4, 554–567 (1988).
A. G. Aleksandrov, “Nonisolated hypersurface singularities,” in: Adv. in Soviet Math. (Arnold V. I., ed.), Vol. 1, Amer. Math. Soc., Providence, RI, 1990, pp. 211–246.
D. Barlet, Le faiseau ω ·X sur un espace analytique X de dimension pure, Lecture Notes in Math., Vol. 670, 187–204, Springer-Verlag, 1978.
X. Gomez-Mont, “An algebraic formula for the index of a vector field on a hypersurface with an isolated singularity,” J. Alg. Geom., 7, 731–752 (1998).
L. Giraldo, X. Gomez-Mont, and P. Mardesic, “On the index of vector fields tangent to hyper-surfaces with non-isolated singularities,” J. London Math. Soc. (2), 65, No.2, 418–438 (2002).
G.-M. Greuel, “Der Gauß-Manin-Zusammenhang isolierter Singularitaten von vollstandigen Durchschnitten,” Math. Ann., 214, No.3, 235–266 (1975).
Ph. Griffiths and J. Harris, Principles of Algebraic Geometry, Pure Appl. Math., Wiley-Interscience, New York, 1978.
R. Hartshorne, Algebraic Geometry, Grad. Texts in Math., Vol. 52, Springer-Verlag, 1977.
J. Milnor, Topology from the Differential Viewpoint, Princeton Univ. Press, Princeton, NJ, 1997.
H.-J. Reiffen and U. Vetter, “Pfaffsche Formen auf komplexen Raumen,” Math. Ann., 167, No. 4, 338–350 (1966).
H. Rossi, “Vector fields on analytic spaces,” Ann. of Math. (2), 78, 455–467 (1963).
K. Saito, “On the uniformization of complements of discriminant loci,” in: Hyperfunctions and Linear partial differential equations, RIMS Koukyuroku, 287, 117–137 (1977).
K. Saito, “Theory of logarithmic differential forms and logarithmic vector fields,” J. Fac. Sci. Univ. Tokyo, Sect. IA Math., 27, No.2, 265–291 (1980).
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Translated from Funktsional'nyi Analiz i Ego Prilozheniya, Vol. 39, No. 4, pp. 1–13, 2005
Original Russian Text Copyright by © A. G. Aleksandrov
The work was supported in part by the Russian Foundation for Basic Research (project 02-01-00623).
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Aleksandrov, A.G. The Index of Vector Fields and Logarithmic Differential Forms. Funct Anal Its Appl 39, 245–255 (2005). https://doi.org/10.1007/s10688-005-0046-0
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DOI: https://doi.org/10.1007/s10688-005-0046-0