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Every right adjoint functor between presentable $\infty$-categories is shown to decompose canonically as a coreflection, followed by, possibly transfinitely many, monadic functors. Furthermore, the coreflection part is given a presentation…

Algebraic Topology · Mathematics 2021-11-23 Lior Yanovski

We show that (under mild assumptions) the generating function of log homology torsion of a knot exterior has a meromorphic continuation to the entire complex plane. As corollaries, this gives new proofs of (a) the Silver-Williams…

Geometric Topology · Mathematics 2017-02-22 Oliver Braunling

We introduce a new functor on categories of modular representations of reductive algebraic groups. Our functor has remarkable properties. For example it is a tensor functor and sends every standard and costandard object in the principal…

Representation Theory · Mathematics 2026-04-28 Joe Baine , Tasman Fell , Anna Romanov , Alexander Sherman , Geordie Williamson

Consider the functor describing deformations of a representation of the fundamental group of a variety X. This paper is chiefly concerned with establishing an analogue in finite characteristic of a result proved by Goldman and Millson for…

Algebraic Geometry · Mathematics 2019-07-04 J. P. Pridham

We present an understandable, efficient, and streamlined proof of the Holonomy Decomposition for finite transformation semigroups and automata. This constructive proof closely follows the existing computational implementation. Its novelty…

Group Theory · Mathematics 2015-08-27 Attila Egri-Nagy , Chrystopher L. Nehaniv

We study functors from spaces to spaces or spectra that preserve weak homotopy equivalences. For each such functor we construct a universal n-excisive approximation, which may be thought of as its n-excisive part. Homogeneous functors,…

Algebraic Topology · Mathematics 2014-11-11 Thomas G. Goodwillie

We provide necessary and/or sufficient conditions for the stable Hom functors to be finitely presented. When the covariant Hom functor modulo projectives is finitely presented, its defect is isomorphic to the Bass torsion of the fixed…

Category Theory · Mathematics 2024-03-21 Alex Martsinkovsky

We use a Hodge decomposition and its generalization to non-abelian flat vector bundles to calculate the partition function for abelian and non- abelian BF theories in $n$ dimensions. This enables us to provide a simple proof that the…

High Energy Physics - Theory · Physics 2009-10-22 J. Gegenberg , G. Kunstatter

The aim of this article is to provide space level maps between configuration spaces of graphs that are predicted by algebraic manipulations of cellular chains. More explicitly, we consider edge contraction and half-edge deletion, and…

Algebraic Topology · Mathematics 2022-01-05 Sanjana Agarwal , Maya Banks , Nir Gadish , Dane Miyata

We analyze the many-particle correlations that affect the optical properties of two-dimensional semiconductors. These correlations manifest themselves through the specific optical resonances such as excitons, trions, etc. Starting from the…

Mesoscale and Nanoscale Physics · Physics 2021-03-24 A. Kudlis , I. Iorsh

In the paper, we give partition-theoretic results for the coefficients of some mock theta functions and prove their congruence properties. Some recurrence relations connecting the coefficients of the mock theta functions with certain…

Number Theory · Mathematics 2024-02-28 Sabi Biswas , Nipen Saikia

We prove that continuous Hochschild and cyclic homology satisfy excision for extensions of nuclear H-unital Frechet algebras and use this to compute them for the algebra of Whitney functions on an arbitrary closed subset of a smooth…

K-Theory and Homology · Mathematics 2015-10-23 Ralf Meyer

We analyze a functor from cyclic operads to chain complexes first considered by Getzler and Kapranov and also Markl. This functor is a generalization of the graph homology considered by Kontsevich, which was defined for the three operads…

Quantum Algebra · Mathematics 2007-05-23 James Conant

We develop a new approach of extension calculus in the category of strict polynomial functors, based on Troesch complexes. We obtain new short elementary proofs of numerous classical Ext-computations as well as new results. In particular,…

Representation Theory · Mathematics 2012-10-18 Antoine Touzé

We introduce lifespan functors, which are endofunctors on the category of persistence modules that filter out intervals from barcodes according to their boundedness properties. They can be used to classify injective and projective objects…

Algebraic Topology · Mathematics 2024-02-21 Ulrich Bauer , Maximilian Schmahl

We show that the components, appearing in the decomposition theorem for contraction maps of torus actions of complexity one, are intersection cohomology complexes of even codimensional subvarieties. As a consequence, we obtain the vanishing…

Algebraic Geometry · Mathematics 2026-03-10 Marta Agustin Vicente , Narasimha Chary Bonala , Kevin Langlois

We prove that the Bredon homology or cohomology of the partition complex with fairly general coefficients is either trivial or computable in terms of constructions with the Steinberg module. The argument involves developing a theory of…

Algebraic Topology · Mathematics 2016-07-12 Gregory Z. Arone , William G. Dwyer , Kathryn Lesh

This paper gives an exposition of well known results on vector partition functions. The exposition is based on works of M. Brion, A. Szenes and M. Vergne and is geared toward explicit computer realizations. In particular, the paper presents…

Representation Theory · Mathematics 2010-11-25 Todor Milev

In this paper we give a proof of an index theorem by Bismut. As a consequence we obtain another proof of the Grothendieck-Riemann-Roch theorem in differential cohomology.

Differential Geometry · Mathematics 2015-07-17 Man-Ho Ho

In this paper, we prove a Maschke type theorem for the category of relative Hom-Hopf modules. In fact, we give necessary and sufficient conditions for the functor that forgets the $(H, \a)$-coaction to be separable. This leads to a…

Rings and Algebras · Mathematics 2014-11-27 Shuang-jian Guo , Xiu-li Chen