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In this article we formalize and enhance Kontsevich's beautiful insight that Chow motives can be embedded into non-commutative ones after factoring out by the action of the Tate object. We illustrate the potential of this result by…

K-Theory and Homology · Mathematics 2011-03-02 Goncalo Tabuada

A motive over a field $k$ is of abelian type if it belongs to the thick and rigid subcategory of Chow motives spanned by the motives of abelian varieties over $k$. This paper contains three sections of independent interest. First, we show…

Algebraic Geometry · Mathematics 2015-07-28 Charles Vial

The goal of this paper is to give an explicit description of the triangulated categories of Tate and Artin-Tate motives with finite coefficients Z/m over a field K containing a primitive m-root of unity as the derived categories of exact…

K-Theory and Homology · Mathematics 2014-04-28 Leonid Positselski

We explore computational tools that allow to compute the class on the Grothendieck ring of varieties of finite cyclic quotients in some interesting examples. As an main application, we determine the motive of low rank representation…

Algebraic Geometry · Mathematics 2025-05-12 Lucas de Amorin

We prove formulas for the rational Chow motives of moduli spaces of semistable vector bundles and Higgs bundles of rank 3 and coprime degree on a smooth projective curve. Our approach involves identifying criteria to lift identities in (a…

Algebraic Geometry · Mathematics 2021-12-21 Lie Fu , Victoria Hoskins , Simon Pepin Lehalleur

Let $G$ be a semi-simple algebraic group over a perfect field $k$. A lot of progress has been made recently in computing the Chow motives of projective $G$-homogenous varieties. When $k$ has positive characteristic, a broader class of…

Algebraic Geometry · Mathematics 2017-10-20 Srimathy Srinivasan

We compute the motive of the classifying stack of an orthogonal group in the Grothendieck ring of stacks over a field of characteristic different from two.

Algebraic Geometry · Mathematics 2018-09-11 Ajneet Dhillon , Matthew B. Young

We construct the motive of an algebraic stack in the Nisnevich topology. For stacks which are Nisnevich locally quotient stacks, we give a presentation of the motive in terms of simplicial schemes. We also show that for quotient stacks the…

Algebraic Geometry · Mathematics 2023-06-21 Utsav Choudhury , Neeraj Deshmukh , Amit Hogadi

Already in the 1960s Grothendieck understood that one could obtain an almost entirely satisfactory theory of motives over a finite field when one assumes the full Tate conjecture. In this note we prove a similar result for motivic…

Algebraic Geometry · Mathematics 2021-01-19 James S. Milne , Niranjan Ramachandran

Recently, the author defined multiple Dedekind zeta values [5] associated to a number K field and a cone C. These objects are number theoretic analogues of multiple zeta values. In this paper we prove that every multiple Dedekind zeta value…

Algebraic Geometry · Mathematics 2018-11-21 Ivan Horozov

This paper investigates the structure of generic motives and their implications for the motivic cohomology of fields. Originating in Voevodsky's theory of motives and related to Beilinson's vision of a motivic $t$-structure, generic motives…

Algebraic Geometry · Mathematics 2025-07-22 F. Déglise

Mixed Tate motives are central objects in the study of cohomology groups of algebraic varieties and their arithmetic invariants. They also play a crucial role in a wide variety of questions related to multiple zeta values and…

Algebraic Geometry · Mathematics 2024-12-31 Clément Dupont

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

Let G be a split semisimple linear algebraic group over a field k0. Let E be a G-torsor over a field extension k of k0. Let h be an algebraic oriented cohomology theory in the sense of Levine-Morel. Consider a twisted form E/B of the…

Algebraic Geometry · Mathematics 2016-06-27 Alexander Neshitov , Victor Petrov , Nikita Semenov , Kirill Zainoulline

For a perfect field $k$, we construct a triangulated category of mixed motives over $k[t]/{(t^{m+1})}$. The ext groups in this category are given by higher Chow groups, and additive higher Chow groups.

Algebraic Geometry · Mathematics 2010-01-29 Amalendu Krishna , Jinhyun Park

We prove a canonical Kunneth decomposition for the motive of a commutative group scheme over a field. Moreover, we show that this decomposition behaves under the group law just as in cohomology. We also deduce applications of the…

Algebraic Geometry · Mathematics 2016-03-18 Giuseppe Ancona , Stephen Enright-Ward , Annette Huber

We develop a notion of exponential motives on general prestacks equipped with a $\mathbf{G}_a$-action, and compare them with Whittaker motives via Gaitsgory's Kirillov model. We then establish foundational results for exponential motives on…

Algebraic Geometry · Mathematics 2026-03-25 Robert Cass , Thibaud van den Hove , Jakob Scholbach

We study the multiplicities of pure motives modulo numerical equivalence, which are defined as scalars comparing the tannakian trace with the ring-theoretic trace. Our general set-up is that of a rigid semi-simple tensor category such that…

Algebraic Geometry · Mathematics 2010-09-13 Bruno Kahn

Let H be a homology theory for algebraic varieties over a field k. To a complete k-variety X, one naturally attaches an ideal of the coefficient ring H(k). We show that, when X is regular, this ideal depends only on the upper Chow motive of…

Algebraic Geometry · Mathematics 2023-08-29 Olivier Haution

Let k be a number field, and let S be a finite set of k-rational points of P^1. We relate the Deligne-Goncharov contruction of the motivic fundamental group of X:=P^1_k- S to the Tannaka group scheme of the category of mixed Tate motives…

Algebraic Geometry · Mathematics 2007-08-31 Hélène Esnault , Marc Levine