Resonant Bands and Local System Cohomology Groups for Real Line Arrangements
نویسندگان
چکیده
منابع مشابه
Real line arrangements and fundamental groups
Let A be a real line arrangement in P(R), and let AC be its complexification. Let CC be the complement P (C) \ ⋃ AC. Let G be the Galois group of C/R. We construct a G-equivariant 2-dimensional strong deformation retract of CC. As an application, we give an explicit presentation of the orbifold fundamental group π1(CC//G), and deduce from it an explicit presentation of the ordinary fundamental ...
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متن کامل0 Local cohomology , arrangements of subspaces and monomial ideals
If k is the field of complex numbers (or, more generally, a field of characteristic zero), the module H i I(R) is known to have a module structure over the Weyl algebra An(k), and one can therefore consider its characteristic cycle, denoted CC(H i I(R)) in this paper (see e.g. [2, I.1.8.5]). On the other hand, the arrangement X defines a partially ordered set P (X) whose elements correspond to ...
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ژورنال
عنوان ژورنال: Vietnam Journal of Mathematics
سال: 2014
ISSN: 2305-221X,2305-2228
DOI: 10.1007/s10013-014-0086-y