English
Related papers

Related papers: Upper motives of outer algebraic groups

200 papers

In the present article we investigate ordinary and equivariant Rost motives. We provide an equivariant motivic decomposition of the variety X of full flags of a split semisimple algebraic group over a smooth base scheme, study torsion…

Algebraic Geometry · Mathematics 2017-06-14 Victor Petrov , Nikita Semenov

In this paper, the Lawson homology and morphic cohomology are defined on the Chow motives. We also define the rational coefficient Lawson homology and morphic cohomology of the Chow motives of finite quotient projective varieties. As a…

Algebraic Geometry · Mathematics 2019-11-01 Wenchuan Hu , Li Li

Given a smooth projective variety $M$ endowed with a faithful action of a finite group $G$, following Jarvis-Kaufmann-Kimura and Fantechi-G\"ottsche, we define the orbifold motive (or Chen-Ruan motive) of the quotient stack $[M/G]$ as an…

Algebraic Geometry · Mathematics 2019-03-13 Lie Fu , Zhiyu Tian , Charles Vial

Working over an algebraically closed field $k$ of characteristic $0$, we show that the motivic stable homotopy groups of the sphere spectrum can be determined entirely from the motivic homotopy groups of the $p$-completed sphere spectra and…

Algebraic Topology · Mathematics 2026-03-10 Sebastian Gant , Ben Williams

The decomposition matrix of a finite group in prime characteristic p records the multiplicities of its p-modular irreducible representations as composition factors of the reductions modulo p of its irreducible representations in…

Representation Theory · Mathematics 2014-10-21 Eugenio Giannelli , Mark Wildon

The deepest arithmetic invariants attached to an algebraic variety defined over a number field $F$ are conjecturally captured by the integral part of its motivic cohomology. There are essentially two ways of defining it when $X$ is a smooth…

Number Theory · Mathematics 2024-02-23 Quentin Gazda

We generalize to the super context, the known fact that if an affine algebraic group $G$ over a commutative ring $k$ acts freely (in an appropriate sense) on an affine scheme $X$ over $k$, then the dur sheaf $X\tilde{\tilde{/}}G$ of…

Algebraic Geometry · Mathematics 2021-08-10 Akira Masuoka , Taiki Shibata , Yuta Shimada

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

We prove that if a smooth projective algebraic variety of dimension less or equal to three has a unit type integral $K$-motive, then its integral Chow motive is of Lefschetz type. As a consequence, the integral Chow motive is of Lefschetz…

Algebraic Geometry · Mathematics 2018-03-29 Sergey Gorchinskiy

In the present article we define an integral analogue of Chow-K\"unneth decomposition for \'etale motives. By using families of conservative functors we are able to establish a decomposition of the \'etale motive of commutative group…

Algebraic Geometry · Mathematics 2024-03-04 Ivan Rosas-Soto

We introduce a family of periods of mixed Tate motives called dissection polylogarithms, that are indexed by combinatorial objects called dissection diagrams. The motivic coproduct on the former is encoded by a combinatorial Hopf algebra…

Algebraic Geometry · Mathematics 2014-10-07 Clément Dupont

We study the Chow motive (with rational coefficients) of a hypersurface X in the projective space by using the variety F(X) of l-dimensional planes contained in X. If the degree of X is sufficiently small we show that the primitive part of…

Algebraic Geometry · Mathematics 2008-01-17 Andre Chatzistamatiou

For any smooth projective moduli space $M$ of Gieseker stable sheaves on a complex projective K3 surface (or an abelian surface) S, we prove that the Chow motive $\mathfrak{h}(M)$ becomes a direct summand of a motive $\bigoplus…

Algebraic Geometry · Mathematics 2018-06-22 Tim-Henrik Bülles

We prove that the projectors arising from the decomposition theorem applied to a projective map of quasi projective varieties are absolute Hodge, Andr\'e motivated, Tate and Ogus classes. As a by-product, we introduce, in characteristic…

Algebraic Geometry · Mathematics 2014-01-16 Mark Andrea A. de Cataldo , Luca Migliorini

We first recall the construction of the Chow motive modelling intersection cohomology of a proper surface and study its fundamental properties. Using Voevodsky's category of effective geometrical motives, we then study the motive of the…

K-Theory and Homology · Mathematics 2017-06-23 J. Wildeshaus

We prove a Hasse principle for binary direct summands of the Chow motive of a smooth projective quadric Q over a number field F. Besides, we show that such summands are twists of Rost motives. In the case when F has at most one real…

Algebraic Geometry · Mathematics 2018-12-24 Mikhail Borovoi , Nikita Semenov , Maksim Zhykhovich

Let D be a central division algebra over a field F. We study in this note the rigidity of the motivic decompositions of the Severi-Brauer varieties of D, with respect to the ring of coefficients and to the base field. We first show that if…

Algebraic Geometry · Mathematics 2012-10-10 Charles De Clercq

We introduce the notion of algebraic cogroup over a subfield $k$ of the complex numbers, and use it to prove that every Nori motive over $k$ is isomorphic to a quotient of a motive of the form $H^n(X, Y)(i)$.

Algebraic Geometry · Mathematics 2018-05-11 Javier Fresán , Peter Jossen

We introduce a theory of motivic cohomology for quasi-compact quasi-separated schemes, which generalises the construction of Elmanto--Morrow in the case of schemes over a field. Our construction is non-$\mathbb{A}^1$-invariant in general,…

Algebraic Geometry · Mathematics 2025-07-22 Tess Bouis

For a quasiprojective variety S, we define a category CHM(S) of pure Chow motives over S. Assuming conjectures of Grothendieck and Murre, we show that the decomposition theorem holds in CHM(S). As a consequence, the intersection complex of…

Algebraic Geometry · Mathematics 2007-05-23 A. Corti , M. Hanamura