Conormal varieties and characteristic varieties
نویسندگان
چکیده
منابع مشابه
Characteristic Classes of Singular Varieties via Conormal Geometry
The main purpose of this paper is to give a short introduction to the theory of characteristic classes of singular varieties via the conormal geometry approach. Our account is far from being complete and is directed mainly to the students who would like to explore the subject. Thus, instead of giving a long list of statements or an exhaustive historical account our purpose is to present the mai...
متن کاملCharacteristic Varieties of Arrangements
The k Fitting ideal of the Alexander invariant B of an arrangement A of n complex hyperplanes defines a characteristic subvariety, Vk(A), of the complex algebraic torus (C). In the combinatorially determined case where B decomposes as a direct sum of local Alexander invariants, we obtain a complete description of Vk(A). For any arrangement A, we show that the tangent cone at the identity of the...
متن کاملCharacteristic Varieties and Constructible Sheaves
We explore the relation between the positive dimensional irreducible components of the characteristic varieties of rank one local systems on a smooth surface and the associated (rational or irrational) pencils. Our study, which may viewed as a continuation of D. Arapura’s paper [1], yields new geometric insight into the translated components relating them to the multiplicities of curves in the ...
متن کاملCharacteristic numbers of algebraic varieties.
A rational linear combination of Chern numbers is an oriented diffeomorphism invariant of smooth complex projective varieties if and only if it is a linear combination of the Euler and Pontryagin numbers. In dimension at least 3, only multiples of the top Chern number, which is the Euler characteristic, are invariant under diffeomorphisms that are not necessarily orientation preserving. In the ...
متن کاملIrreducible components of characteristic varieties
We give a dimension bound on the irreducible components of the characteristic variety of a system of linear partial di.erential equations de0ned from a suitable 0ltration of the Weyl algebra An. This generalizes an important consequence of the fact that a characteristic variety de0ned from the order 0ltration is involutive. More explicitly, we consider a 0ltration of An induced by any vector (u...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1999
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-99-05137-0