2 3 Ju l 2 00 7 Andersen Filtration and Hard Lefschetz Wolfgang Soergel February 2 , 2008 For
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چکیده
On the space of homomorphisms from a Verma module to an indecomposable tilting module of the BGG-category O we define a natural filtration following Andersen [And97] and establish a formula expressing the dimensions of the filtration steps in terms of coefficients of Kazhdan-Lusztig polynomials.
منابع مشابه
Andersen-Filtration and Hard Lefschetz
We consider the principal block of category O and its Z-graded version introduced in [BGS96]. On the space of homomorphisms from a Verma module to an indecomposable tilting module we define a natural filtration following Andersen [And97]. The arguments given in this article prove that these filtrations are compatible with the Zgraded structure, although we only show explicitly that the dimensio...
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تاریخ انتشار 2008