The essential ideal in group cohomology does not square to zero
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منابع مشابه
The essential ideal in group cohomology does not square to zero
Let G be the Sylow 2-subgroup of the unitary group SU 3(4). We find two essential classes in the mod 2 cohomology ring of G whose product is nonzero. In fact, the product is the “last survivor” of Benson–Carlson duality. Recent work of Pakianathan and Yalçın then implies a result about connected graphs with an action of G. Also, there exist essential classes which cannot be written as sums of t...
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ژورنال
عنوان ژورنال: Journal of Pure and Applied Algebra
سال: 2004
ISSN: 0022-4049
DOI: 10.1016/j.jpaa.2004.03.007