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This paper proposes an axiomatic for Cyclic Foam Topological Field theories. That is Topological Field theories, corresponding to String theories, where particles are arbitrary graphs. World surfaces in this case are two-manifolds with…

Geometric Topology · Mathematics 2010-05-07 S. M. Natanzon

We study classes $P_{g,T}(\alpha;\beta)$ on the moduli space of stable, genus g curves with rational tails defined by pushing forward the virtual fundamental classes of spaces of relative stable maps to an unparameterized projective line. A…

Algebraic Geometry · Mathematics 2011-07-06 Renzo Cavalieri , Steffen Marcus , Jonathan Wise

Arithmetic duality theorems over a local field $k$ are delicate to prove if $\mathrm{char} k > 0$. In this case, the proofs often exploit topologies carried by the cohomology groups $H^n(k, G)$ for commutative finite type $k$-group schemes…

Number Theory · Mathematics 2015-08-10 Kestutis Cesnavicius

Simplicial toric stack bundles are smooth Deligne-Mumford stacks over smooth varieties with fibre a toric Deligne-Mumford stack. We compute the Grothendieck $K$-theory of simplicial toric stack bundles and study the Chern character…

Algebraic Geometry · Mathematics 2011-01-20 Yunfeng Jiang , Hsian-Hua Tseng

We introduce a convenient framework for constructing and analyzing orthogonal Thom spectra arising from virtual vector bundles. This framework enables us to set up a theory of orientations and graded Thom isomorphisms with good…

Algebraic Topology · Mathematics 2019-07-15 Steffen Sagave , Christian Schlichtkrull

In a previous article, a universal linear algebraic model was proposed for describing homogeneous conformal geometries, such as the spherical, Euclidean, hyperbolic, Minkowski, anti-de Sitter and Galilei planes. This formalism was…

Metric Geometry · Mathematics 2018-04-12 Mate Lehel Juhasz

Quantum homogeneous vector bundles are introduced by a direct description of their sections in the context of Woronowicz type compact quantum groups. The bundles carry natural topologies inherited from the quantum groups, and their sections…

q-alg · Mathematics 2008-02-03 A. R. Gover , R. B. Zhang

We provide a stratification of the $\mathrm{AGL}_r(\mathbb{C})$-representation variety of the fundamental group of the complement of a twisted Hopf link in terms of a stratification of the corresponding…

Geometric Topology · Mathematics 2026-05-14 Ángel Molina-Navarro

We provide a recursive formula for the motivic class of the noncommutative Quot scheme in the Grothendieck ring of stacks.

Algebraic Geometry · Mathematics 2023-03-21 Andrea T. Ricolfi

Let $\Sigma_{g'}\to \Sigma_g$ be a cover of an orientable surface of genus g by an orientable surface of genus g', branched at n points, with Galois group H. Such a cover induces a virtual action of the mapping class group…

Algebraic Geometry · Mathematics 2025-10-14 Aaron Landesman , Daniel Litt , Will Sawin

We construct a two dimensional unoriented open/closed topological field theory from a finite graded group $\pi:\hat{G} \twoheadrightarrow \{1,-1\}$, a $\pi$-twisted $2$-cocycle $\hat{\theta}$ on $B \hat{G}$ and a character $\lambda: \hat{G}…

Representation Theory · Mathematics 2023-10-06 Levi Gagnon-Ririe , Matthew B. Young

We propose the notion of q-characters for finite-dimensional representations of quantum affine algebras. It is motivated by our theory of deformed W-algebras. We show that the q-characters give rise to a homomorphism from the Grothendieck…

Quantum Algebra · Mathematics 2008-11-10 Edward Frenkel , Nicolai Reshetikhin

In this paper, we construct and study derived character maps of finite-dimensional representations of $\infty$-groups. As models for $\infty$-groups we take homotopy simplicial groups, i.e. homotopy simplicial algebras over the algebraic…

Algebraic Topology · Mathematics 2025-01-01 Yuri Berest , Ajay C. Ramadoss

In this paper we study the topology of the stack $\mathcal{T}_g$ of smooth trigonal curves of genus g, over the complex field. We make use of a construction by the first named author and Vistoli, that describes $\mathcal{T}_g$ as a quotient…

Algebraic Geometry · Mathematics 2016-04-12 Michele Bolognesi , Michael Lönne

We define the character of a group representation in a 2-category C. For linear C, this notion yields a Hopkins-Kuhn-Ravenel type character theory defined on pairs of commuting elements of the group. We discuss some examples and prove a…

K-Theory and Homology · Mathematics 2011-10-11 Nora Ganter , Mikhail Kapranov

The Steinitz class of a number field extension K/k is an ideal class in the ring of integers O_k of k, which, together with the degree [K:k] of the extension determines the O_k-module structure of O_K. We call rt(k,G) the classes which are…

Number Theory · Mathematics 2010-05-13 Alessandro Cobbe

For a (semi-)model category M, we define a notion of a ''homotopy'' Grothendieck topology on M, as well as its associated model category of stacks. We use this to define a notion of geometric stack over a symmetric monoidal base model…

Algebraic Geometry · Mathematics 2007-05-23 Bertrand Toen , Gabriele Vezzosi

In this paper we construct full support character sheaves for stably graded Lie algebras. Conjecturally these are precisely the cuspidal character sheaves. Irreducible representations of Hecke algebras associated to complex reflection…

Representation Theory · Mathematics 2025-03-25 Kari Vilonen , Ting Xue

The subring of the Grothendieck ring of varieties generated by the graph hypersurfaces of quantum field theory maps to the monoid ring of stable birational equivalence classes of varieties. We show that the image of this map is the copy of…

Algebraic Geometry · Mathematics 2011-03-02 Paolo Aluffi , Matilde Marcolli

In this short note we show that representation and character varieties of discrete groups can be viewed as tensor products of suitable functors over the PROP of cocommutative Hopf algebras. Such view point has several interesting…

Rings and Algebras · Mathematics 2016-10-11 Martin Kassabov , Sasha Patotski