Higher order cohomology operations in the p-torsion-free category
نویسندگان
چکیده
منابع مشابه
Higher order Hochschild cohomology
Following ideas of Pirashvili, we define higher order Hochschild cohomology over spheres S defined for any commutative algebra A and module M . When M = A, we prove that this cohomology is equipped with graded commutative algebra and degree d Lie algebra structures as well as with Adams operations. All operations are compatible in a suitable sense. These structures are related to Brane topology...
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For every prime integer p, M. Hochster conjectured the existence of certain p-torsion elements in a local cohomology module over a regular ring of mixed characteristic. We show that Hochster’s conjecture is false. We next construct an example where a local cohomology module over a hypersurface has p-torsion elements for every prime integer p, and consequently has infinitely many associated prim...
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A formula due to Grothendieck, Ogg, and Shafarevich gives the EulerPoincaré characteristic of a constructible sheaf of Fl-modules on a smooth, proper curve over an algebraically closed field k of characteristic p > 0, as a sum of a global term and local terms, where l 6= p. A previously known result removes the restriction on l in the case of p-torsion sheaves trivialized by p-extensions. The a...
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Gennady Lyubeznik conjectured that if R is a regular ring and a is an ideal of R, then the local cohomology modules H i a(R) have only finitely many associated prime ideals, [Ly1, Remark 3.7 (iii)]. While this conjecture remains open in this generality, several results are now available: if the regular ring R contains a field of prime characteristic p > 0, Huneke and Sharp showed in [HS] that t...
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A discrete group G has periodic cohomology over R if there is an element α ∈ Ext RG (R,R) of positive degree and an integer n ≥ 0 such that the cup product map by α induces an isomorphism of Ext RG (R,−) and Ext i+|α| RG (R,−) for i ≥ n. Adem and Smith [1] showed if R = Z, then this condition is equivalent to the existence of a finite dimensional free-G-CW-complex homotopy equivalent to a spher...
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ژورنال
عنوان ژورنال: Indagationes Mathematicae (Proceedings)
سال: 1982
ISSN: 1385-7258
DOI: 10.1016/s1385-7258(82)80010-3