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Cohomologie des algèbres de Lie croisées et K -théorie de Milnor additive

Daniel Guin (1995)

Annales de l'institut Fourier

Dans cet article, nous définissons des modules de (co)-homologie 0 ( 𝔊 , 𝔄 ) , 1 ( 𝔊 , 𝔄 ) , ( 𝔊 , 𝔄 ) , 1 ( 𝔊 , 𝔄 ) 𝔊 et 𝔄 sont des algèbres de Lie munies d’une structure supplémentaire (algèbres de Lie croisées), qui satisfont les propriétés usuelles des foncteurs cohomologiques. Si A est une k -algèbre, nous utilisons ces modules d’homologie pour comparer le groupe d’homologie cyclique H C 1 ( A ) avec un analogue additif du groupe de K -théorie de Milnor K 2 Madd ( A ) .

Cohomologies bivariantes de type cyclique

Nikolay V. Solodov (2005)

Annales mathématiques Blaise Pascal

In the article we propose a construction of bivariant cohomology of a couple of chain complexes with periodicities. In this way we obtain definitions of bivariant dihedral and bivariant reflective cohomology of an algebra A . Bivariant cyclic and quaternionic cohomologies appear as particular cases of this construction. The case of 2 invertible in the ground ring is studied particulary.Dans cet article nous proposons une définition de la cohomologie bivariante pour une paire de complexes de chaînes...

Cohomology operations and the Deligne conjecture

Martin Markl (2007)

Czechoslovak Mathematical Journal

The aim of this note, which raises more questions than it answers, is to study natural operations acting on the cohomology of various types of algebras. It contains a lot of very surprising partial results and examples.

Co-H-structures on equivariant Moore spaces

Martin Arkowitz, Marek Golasiński (1994)

Fundamenta Mathematicae

Let G be a finite group, 𝕆 G the category of canonical orbits of G and A : 𝕆 G 𝔸 b a contravariant functor to the category of abelian groups. We investigate the set of G-homotopy classes of comultiplications of a Moore G-space of type (A,n) where n ≥ 2 and prove that if such a Moore G-space X is a cogroup, then it has a unique comultiplication if dim X < 2n - 1. If dim X = 2n-1, then the set of comultiplications of X is in one-one correspondence with E x t n - 1 ( A , A A ) . Then the case G = p k leads to an example of infinitely...

Colimit-dense subcategories

Jiří Adámek, Andrew D. Brooke-Taylor, Tim Campion, Leonid Positselski, Jiří Rosický (2019)

Commentationes Mathematicae Universitatis Carolinae

Among cocomplete categories, the locally presentable ones can be defined as those with a strong generator consisting of presentable objects. Assuming Vopěnka’s Principle, we prove that a cocomplete category is locally presentable if and only if it has a colimit dense subcategory and a generator consisting of presentable objects. We further show that a 3 -element set is colimit-dense in 𝐒𝐞𝐭 op , and spaces of countable dimension are colimit-dense in 𝐕𝐞𝐜 op .

Currently displaying 181 – 200 of 346