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Related papers: Separation and excision in functor homology

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We show that representations up to homotopy can be differentiated in a functorial way. A van Est type isomorphism theorem is established and used to prove a conjecture of Crainic and Moerdijk on deformations of Lie brackets.

Differential Geometry · Mathematics 2010-06-09 Camilo Arias Abad , Florian Schaetz

For any additive functor from modules (or, more generally, from an abelian category with enough projectives or injectives), we construct long sequences tying up together the derived functors, the satellites, and the stabilizations of the…

Representation Theory · Mathematics 2025-04-30 Alex Martsinkovsky

We investigate the structure of graded commutative exponential functors. We give applications of these structure results, including computations of the homology of the symmetric groups and of extensions in the category of strict polynomial…

K-Theory and Homology · Mathematics 2020-02-18 Antoine Touzé

We generalize a special case of a theorem of Proctor on the enumeration of lozenge tilings of a hexagon with a maximal staircase removed, using Kuo's graphical condensation method. Additionally, we prove a formula for a weighted version of…

Combinatorics · Mathematics 2015-10-16 Ranjan Rohatgi

We study the category $\mathcal{O}$ for a general Coxeter system using a formulation of Fiebig. The translation functors, the Zuckerman functors and the twisting functors are defined. We prove the fundamental properties of these functors,…

Representation Theory · Mathematics 2009-04-20 Noriyuki Abe

We proof here the existence of a topological thick and thin decomposition of any closed definable thick isolated singularity germ in the spirit of the recently discovered metric thick and thin decomposition of complex normal surface…

Metric Geometry · Mathematics 2012-08-22 Lev Birbrair , Alexandre Fernandes , Vincent Grandjean

The results in this paper concern computations of Floer cohomology using generating functions. The first part proves the isomorphism between Floer cohomology and Generating function cohomology introduced by Lisa Traynor. The second part…

Symplectic Geometry · Mathematics 2018-05-04 C Viterbo

The Separation of Variables theory for the Hamilton-Jacobi equation is 'by definition' related to the use of special kinds of coordinates, for example Jacobi coordinates on the ellipsoid or St\"ackel systems in the Euclidean space. However,…

Mathematical Physics · Physics 2009-07-20 Giovanni Rastelli

We give characterizations of the separability of the induction and ad-induction functors associated to a coring morphism.

Rings and Algebras · Mathematics 2007-05-23 J. Gomez-Torrecillas

We develop a theory of separable ring extensions and separable functors for nonunital rings in the setting of firm modules. We prove nonunital analogues of classical results on functorial separability and semisimplicity, and apply these…

Rings and Algebras · Mathematics 2026-05-26 Patrik Lundström

We introduce the notions of Koszul $N$-complex, $\check{\mathrm{C}}$ech $N$-complex and telescope $N$-complex, explicit derived torsion and derived completion functors in the derived category $\mathbf{D}_N(R)$ of $N$-complexes using the…

Commutative Algebra · Mathematics 2020-06-24 Xiaoyan Yang

We construct a category $\mathrm{HomCob}$ whose objects are {\it homotopically 1-finitely generated} topological spaces, and whose morphisms are {\it cofibrant cospans}. Given a manifold submanifold pair $(M,A)$, we prove that there exists…

Mathematical Physics · Physics 2022-09-01 Fiona Torzewska

This paper exhibits fundamental structure underlying Lie algebra homology with coefficients in tensor products of the adjoint representation, mostly focusing upon the case of free Lie algebras. The main result yields a DG category that is…

Algebraic Topology · Mathematics 2023-09-15 Geoffrey Powell

We develop a theory of Goodwillie calculus for functors between $G$-equivariant homotopy theories, where $G$ is a finite group. We construct $J$-excisive approximations of a homotopy functor for any finite $G$-set $J$. These fit together…

Algebraic Topology · Mathematics 2017-03-29 Emanuele Dotto

Starting from the results in math.DG:1212.3161 we prove that for a given Bianchi group, certain natural coefficent modules and a lot of sequences of congruence subgroups of the size of the torsion subgroup of the first homology grows…

Geometric Topology · Mathematics 2018-02-14 Jean Raimbault

We show that a single special separation theorem (namely, a consequence of the geometric form of the Hahn-Banach theorem) can be used to prove Farkas type theorems, existence theorems for numerical quadrature with positive coefficients, and…

Functional Analysis · Mathematics 2018-01-01 Frank Deutsch , Hein Hundal , Ludmil Zikatanov

We apply poset cocalculus, a functor calculus framework for functors out of a poset, to study the problem of decomposing multipersistence modules into simpler components. We both prove new results in this topic and offer a new perspective…

Algebraic Topology · Mathematics 2025-10-09 Bjørnar Gullikstad Hem

We prove that extension groups in strict polynomial functor categories compute the rational cohomology of classical algebraic groups. This result was previously known only for general linear groups. We give several applications to the study…

Representation Theory · Mathematics 2010-12-13 Antoine Touzé

We demonstrate that an excision property holds for persistent homology groups. This property holds for a large class of filtrations, and in fact we show that given any filtration on a larger space, we can extend it to a filtration of two…

Algebraic Topology · Mathematics 2019-10-09 Megan Palser

We give necessary and sufficient conditions for the functor that forgets the $(C, \gamma)$-coaction to be separable. This leads to a generalized notion of integrals. Finally, the applications of our results are considered.

Rings and Algebras · Mathematics 2015-01-13 Shuangjian Guo , Xiaohui Zhang