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Related papers: Motivic twisted K-theory

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This paper continues the author's program to investigate the question of when a homotopy of 2-cocycles $\Omega = \{\omega_t\}_{t \in [0,1]}$ on a locally compact Hausdorff groupoid $\mathcal{G}$ induces an isomorphism of the $K$-theory…

Operator Algebras · Mathematics 2014-10-28 Elizabeth Gillaspy

We investigate the tensor-triangular geometry of the categories of isotropic Tate motives, isotropic Artin motives and isotropic Artin--Tate motives. In particular, we study the categories $DTM_{gm}(k/k;\mathbb{F}_2)$,…

Algebraic Geometry · Mathematics 2025-11-11 Fraser Sparks

For a linear algebraic group $G$ over a field $k$, we define an equivariant version of the Voevodsky's motivic cobordism $MGL$. We show that this is an oriented cohomology theory with localization sequence on the category of smooth…

Algebraic Geometry · Mathematics 2012-06-27 Amalendu Krishna

We examine the slice spectral sequence for the cohomology of singular schemes with respect to various motivic T-spectra, especially the motivic cobordism spectrum. When the base field k admits resolution of singularities and X is a scheme…

Algebraic Geometry · Mathematics 2018-12-26 Amalendu Krishna , Pablo Pelaez

We find three families of twisting maps of K^m with K^n. One of them is related to truncated quiver algebras, the second one consists of deformations of the first and the third one requires m=n and yields algebras isomorphic to M_n(K).…

Rings and Algebras · Mathematics 2016-03-04 J. Arce , Jorge A. Guccione , Juan J. Guccione , C. Valqui

Let G be a discrete group. We give methods to compute for a generalized (co-)homology theory its values on the Borel construction (EG x X)/G of a proper G-CW-complex X satisfying certain finiteness conditions. In particular we give formulas…

K-Theory and Homology · Mathematics 2012-01-24 Michael Joachim , Wolfgang Lueck

For $k$ a perfect field of characteristic $p>0$ and $G/k$ a split reductive group with $p$ a non-torsion prime for $G,$ we compute the mod $p$ motivic cohomology of the geometric classifying space $BG_{(r)}$, where $G_{(r)}$ is the $r$th…

Algebraic Geometry · Mathematics 2022-12-21 Eric Primozic

An equivariant Thom isomorphism theorem in operator K-theory is formulated and proven for infinite rank Euclidean vector bundles over finite dimensional Riemannian manifolds. The main ingredient in the argument is the construction of a…

K-Theory and Homology · Mathematics 2007-05-23 Jody Trout

Infinite loop space theory, both additive and multiplicative, arose largely from two basic motivations. One was to solve calculational questions in geometric topology. The other was to better understand algebraic K-theory. The Adams…

Algebraic Topology · Mathematics 2009-03-17 J. P. May

We establish conditions under which an inclusion of finitely aligned left-cancellative small categories induces inclusions of twisted C*-algebras. We also present an example of an inclusion of finitely aligned left-cancellative monoids that…

Operator Algebras · Mathematics 2025-06-24 Alexander Mundey , Aidan Sims

Quillen's algebraic K-theory is reconstructed via Voevodsky's algebraic cobordism. More precisely, for a ground field k the algebraic cobordism P^1-spectrum MGL of Voevodsky is considered as a commutative P^1-ring spectrum. There is a…

Algebraic Geometry · Mathematics 2009-11-13 I. Panin , K. Pimenov , O. Röndigs

Let K_0(V/X) be the relative Grothendieck group of varieties over X in obj(V), with V the category of (quasi-projective) algebraic (resp. compact complex analytic) varieties over a base field k. Then we constructed the motivic Hirzebruch…

Algebraic Geometry · Mathematics 2013-10-02 Joerg Schuermann , Shoji Yokura

Assuming the K\"unneth type standard conjecture, we propose a way to describe objects of mixed motives explicitly. We study their formal properties, and we associate mixed motives to schemes smooth and separated over a field. This serves as…

Algebraic Geometry · Mathematics 2020-01-31 Doosung Park

In order to treat multiplicative phenomena in twisted (co)homology, we introduce a new point-set level framework for parametrized homotopy theory. We provide a convolution smash product that descends to the corresponding…

Algebraic Topology · Mathematics 2020-03-20 Fabian Hebestreit , Steffen Sagave , Christian Schlichtkrull

We consider twisted equivariant K--theory for actions of a compact Lie group $G$ on a space $X$ where all the isotropy subgroups are connected and of maximal rank. We show that the associated rational spectral sequence \`a la Segal has a…

Algebraic Topology · Mathematics 2019-10-01 Alejandro Adem , José Cantarero , José Manuel Gómez

The purpose of this paper is twofold. First, we use the motivic Landweber exact functor theorem to deduce that the Bott inverted infinite projective space is homotopy algebraic $K$-theory. The argument is considerably shorther than any…

Algebraic Geometry · Mathematics 2008-10-17 Niko Naumann , Markus Spitzweck , Paul Arne Østvær

Consider the Tate twist $\tau \in H^{0,1}(S^{0,0})$ in the mod 2 cohomology of the motivic sphere. After 2-completion, the motivic Adams spectral sequence realizes this element as a map $\tau \colon S^{0,-1} \to S^{0,0}$, with cofiber…

Algebraic Topology · Mathematics 2017-01-19 Bogdan Gheorghe

For twisted K-theory whose twist is classified by a degree three integral cohomology of infinite order, universal even degree characteristic classes are in one to one correspondence with invariant polynomials of Atiyah and Segal. The…

Algebraic Topology · Mathematics 2010-06-04 Kiyonori Gomi

In this paper, we introduce Kasparov's bivariant K-theory that is equivariant under symmetries of a C*-tensor category. It is motivated by some dualities in quantum group equivariant KK-theory, and the classification theory of inclusions of…

Operator Algebras · Mathematics 2025-03-19 Yuki Arano , Kan Kitamura , Yosuke Kubota

This paper addresses the problem of calculating the Amitsur subgroup of a proper $k$-scheme. Under mild hypothesis, we calculate this subgroup for proper $k$-varieties $X$ with $\mathrm{Pic}(X)\simeq \mathbb{Z}^{\oplus m}$, using a…

Algebraic Geometry · Mathematics 2021-01-29 Saša Novaković