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The construction of characteristic classes via the curvature form of a connection is one motivation for the refinement of integral cohomology by de Rham cocycles -- known as differential cohomology. We will discuss the analog in the case of…

Differential Geometry · Mathematics 2015-11-11 Andreas Kübel , Andreas Thom

We construct models for the classifying spaces of coabelian subgroups of right-angled Coxeter groups as homotopy orbit spaces of real moment-angle complexes, generalizing well-known models for the classifying space of a right-angled Coxeter…

Algebraic Topology · Mathematics 2026-04-24 Steven Amelotte , Vladimir Gorchakov

A rational group of hermitian type is an algebraic group over the rational numbers whose symmetric space is a hermitian symmetric space. We assume such a group $G$ to be given, which we assume is isotropic. Then, for any rational parabolic…

alg-geom · Mathematics 2008-02-03 Bruce Hunt

Let $C_\bullet$ be a simplicial object in the category $Cat$ of small categories. For a field $k$, taking the Grothendieck groups of isomorphism classes of $kC_n$-modules gives rise to a cochain complex, whose cohomology, which we refer to…

Representation Theory · Mathematics 2026-04-23 Markus Klemetti , Ran Levi , Henri Riihimaki , Daniel Solch

We present a formal scheme based cycle model for the motivic cohomology of the fat points defined by the truncated polynomial rings $k[t]/(t^m)$ with $m \geq 2$, in one variable over a field $k$. We compute their Milnor range cycle class…

Algebraic Geometry · Mathematics 2022-08-16 Jinhyun Park

We introduce the notion of a manifold admitting a simple compact Cartan 3-form $\om^3$. We study algebraic types of such manifolds specializing on those having skew-symmetric torsion, or those associated with a closed or coclosed 3-form…

Differential Geometry · Mathematics 2013-04-04 Hong Van Le

We consider a closed odd-dimensional oriented manifold $M$ together with an acyclic flat hermitean vector bundle $\cF$. We form the trivial fibre bundle with fibre $M$ over the manifold of all Riemannian metrics on $M$. It has a natural…

dg-ga · Mathematics 2007-05-23 U. Bunke

We study the coherent cohomology of automorphic sheaves corresponding to Siegel modular forms $f$ of low weight on ${\rm GSp}(4)$ Shimura varieties. Inspired by the work of Prasanna--Venkatesh on singular cohomology of locally symmetric…

Number Theory · Mathematics 2025-11-03 Aleksander Horawa , Kartik Prasanna

Over a field of characteristic zero, we establish the homotopy invariance of the Nisnevich cohomology of homotopy invariant presheaves with oriented weak transfers, and the agreement of Zariski and Nisnevich cohomology for such presheaves.…

K-Theory and Homology · Mathematics 2014-05-02 Joseph Ross

We present some data on the cohomology of the motivic Steenrod algebra over an algebraically closed field. We discuss several features of the associated Adams spectral sequence, including the basic construction and convergence properties.…

Algebraic Topology · Mathematics 2009-01-13 Daniel Dugger , Daniel C. Isaksen

Motivated by Murre's work on universal regular homomorphisms on Chow groups in codimension $2,$ we generalize the algebraic equivalence relation and regular homomorphisms to the context of Voevodsky motives over a field. In the Nisnevich…

Algebraic Geometry · Mathematics 2024-12-24 Tohru Kohrita , with an appendix by Bruno Kahn

A theory of characteristic classes of vector bundles and smooth manifolds plays an important role in the theory of smooth manifolds. An investigation of reasonable notions of characteristic classes of singular spaces started since a…

Algebraic Geometry · Mathematics 2007-05-23 Joerg Schuermann , Shoji Yokura

We give a definition of differentiable cohomology of a Lie group G (possibly infinite-dimensional) with coefficients in any abelian Lie group. This differentiable cohomology maps both to the cohomology of the group made discrete and to Lie…

Differential Geometry · Mathematics 2007-05-23 Jean-Luc Brylinski

Motivated by the work of Cappell, Deturck, Gluch and Miller, we extend the notion of cohomology of harmonic forms (of a compact manifold with boundary) to the abstract setting of Hilbert complexes. Then, we present some geometric…

Differential Geometry · Mathematics 2025-12-17 Francesco Bei , Mauro Spreafico

Using the machinery of the Batalin-Vilkovisky formalism, we construct cohomology classes on compactifications of the moduli space of Riemann surfaces from the data of a contractible differential graded Frobenius algebra. We describe how…

Quantum Algebra · Mathematics 2011-05-09 Alastair Hamilton

We develop the theory of Milnor-Witt motives and motivic cohomology. Compared to Voevodsky's theory of motives and his motivic cohomology, the first difference appears in our definition of Milnor-Witt finite correspondences, where our…

Algebraic Geometry · Mathematics 2022-04-05 Tom Bachmann , Baptiste Calmès , Frédéric Déglise , Jean Fasel , Paul Arne Østvær

In this note, we give a motivic characterization of the integral cohomology of dual boundary complexes of smooth quasi-projective complex algebraic varieties. As a corollary, the dual boundary complex of any stably affine space (of positive…

Algebraic Geometry · Mathematics 2024-09-02 Tao Su

We define symmetry classes and commutation symmetries in the Hilbert space H of the 1D spin-1/2 Heisenberg magnetic ring with N sites and investigate them by means of tools from the representation theory of symmetric groups S_N such as…

Combinatorics · Mathematics 2009-11-13 Bernd Fiedler

The relative Grothendieck group $K_0(\m V/X)$ is the free abelian group generated by the isomorphism classes of complex algebraic varieties over $X$ modulo the "scissor relation". The motivic Hirzebruch class ${T_y}_*: K_0(\m V /X) \to…

Algebraic Geometry · Mathematics 2011-10-13 Shoji Yokura

We investigate cohomological invariants and motivic invariants of semisimple algebraic groups arising in the Freudenthal magic square. Besides, we show that if the Rost invariant of a strongly inner group of type $E_7$ is a sum of at most…

Algebraic Geometry · Mathematics 2026-05-05 Nikita Geldhauser , Alexander Henke , Maksim Zhykhovich
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