English
Related papers

Related papers: The motivic fundamental groupoid at tangential bas…

200 papers

For each configuration of rational points on the affine line, we define an operation on the group of unstable A1 motivic homotopy classes of endomorphisms of the projective line. We also derive an algebraic formula for the image of such an…

Algebraic Topology · Mathematics 2025-11-11 John Igieobo , Stephen McKean , Steven Sanchez , Dae'Shawn Taylor , Kirsten Wickelgren

Grothendieck first defined the notion of a "motif" as a way of finding a universal cohomology theory for algebraic varieties. Although this program has not been realized, Voevodsky has constructed a triangulated category of geometric…

Algebraic Geometry · Mathematics 2010-07-13 Anandam Banerjee

We define a linear structure on Grothendieck's arithmetic fundamental group $\pi_1(X, x)$ of a scheme $X$ defined over a field $k$ of characteristic 0. It allows us to link the existence of sections of the Galois group ${\rm Gal}(\bar k/k)$…

Algebraic Geometry · Mathematics 2007-05-23 Hélène Esnault , Phùng Hô Hai

We define motivic iterated integrals on the affine line, and give a simple proof of the formula for the coproduct in the Hopf algebra of they make. We show that it encodes the group law in the automorphism group of certain non-commutative…

Algebraic Geometry · Mathematics 2007-05-23 A. B. Goncharov

We prove the existence of a power structure over the Grothendieck ring of geometric dg categories. We show that a conjecture by Galkin and Shinder (proved recently by Bergh, Gorchinskiy, Larsen, and Lunts) relating the motivic and…

Algebraic Geometry · Mathematics 2025-03-24 Ádám Gyenge

We introduce a variant of stable logarithmic maps, which we call punctured logarithmic maps. They allow an extension of logarithmic Gromov-Witten theory in which marked points have a negative order of tangency with boundary divisors. As a…

Algebraic Geometry · Mathematics 2024-10-01 Dan Abramovich , Qile Chen , Mark Gross , Bernd Siebert

We develop the motivic integration theory over formal Deligne-Mumford stacks over a power series ring of arbitrary characteristic. This is a generalization of the corresponding theory for tame and smooth Deligne-Mumford stacks constructed…

Algebraic Geometry · Mathematics 2024-02-27 Takehiko Yasuda

We define the logarithmic tautological rings of the moduli spaces of Deligne-Mumford stable curves (together with a set of additive generators lifting the decorated strata classes of the standard tautological rings). While these algebras…

Algebraic Geometry · Mathematics 2025-05-15 Rahul Pandharipande , Dhruv Ranganathan , Johannes Schmitt , Pim Spelier

We construct a motivic Eilenberg-MacLane spectrum with a highly structured multiplication over smooth schemes over Dedekind domains which represents Levine's motivic cohomology. The latter is defined via Bloch's cycle complexes. Our method…

Algebraic Geometry · Mathematics 2013-11-20 Markus Spitzweck

We start by developing a theory of noncommutative (=NC) mixed motives with coefficients in any commutative ring. In particular, we construct a symmetric monoidal triangulated category of NC mixed motives, over a base field k, and a full…

Algebraic Geometry · Mathematics 2014-12-30 Goncalo Tabuada

Let $\mathfrak{Var}_k^G$ denote the category of pairs $(X,\sigma)$, where $X$ is a variety over $k$ and $\sigma$ is a group action on $X$. We define the Grothendieck ring for varieties with group actions as the free abelian group of…

Algebraic Geometry · Mathematics 2011-03-14 Justin Mazur

The main results of this paper are a Cell Decomposition Theorem for Henselian valued fields with analytic structure in an analytic Denef-Pas language, and its application to analytic motivic integrals and analytic integrals over…

Algebraic Geometry · Mathematics 2007-05-23 R. Cluckers , L. Lipshitz , Z. Robinson

The main objective of this work is to study mathematical properties of computational paths. Originally proposed by de Queiroz \& Gabbay (1994) as `sequences or rewrites', computational paths are taken to be terms of the identity type of…

Logic in Computer Science · Computer Science 2016-09-09 Arthur F. Ramos , Ruy J. G. B. de Queiroz , Anjolina G. de Oliveira

Ever since the introduction of motivic homotopy theory, as a well-proposed approximation of Grothendieck's dream, algebraic geometers then have the chance to study schemes via a homotopy theory. However topologists also found that lifting…

Algebraic Geometry · Mathematics 2025-12-09 Xin Tong

We develop a general theory which enables the computation of the Picard group of a symmetric monoidal triangulated category, equipped with a weight structure, in terms of the Picard group of the associated heart. As an application, we…

Algebraic Geometry · Mathematics 2016-01-05 Mikhail Bondarko , Goncalo Tabuada

The goal of this paper is to prove: if certain 'standard' conjectures on motives over algebraically closed fields hold, then over any 'reasonable' $S$ there exists a motivic $t$-structure for the category of Voevodsky's $S$-motives (as…

Algebraic Geometry · Mathematics 2015-05-27 Mikhail V. Bondarko

We give the first examples of finite groups G such that the Chow ring of the classifying space BG depends on the base field, even for fields containing the algebraic closure of Q. As a tool, we give several characterizations of the…

Algebraic Geometry · Mathematics 2016-09-21 Burt Totaro

We construct derived fundamental group schemes for Tate motives over connected smooth schemes over fields. We show that there exists a pro affine derived group scheme over the rationals such that its category of perfect representations…

Algebraic Geometry · Mathematics 2010-11-02 Markus Spitzweck

We improve some foundational connectivity results and the relative Hurewicz theorem in motivic homotopy theory, study functorial central series in motivic local group theory, establish the existence of functorial Moore--Postnikov…

Algebraic Geometry · Mathematics 2025-12-03 Aravind Asok , Tom Bachmann , Michael J. Hopkins

We generalize the motivic incarnation morphism from the theory of arithmetic integration to the relative case, where we work over a base variety S over a field k of characteristic zero. We develop a theory of constructible effective Chow…

Algebraic Geometry · Mathematics 2016-09-07 Johannes Nicaise