English
Related papers

Related papers: Doubly Commuting Semigroups of Isometries

200 papers

We show that nonabelian duality is not a symmetry of a conformal field theory, but rather a symmetry between different theories. We expose a nonlocal symmetry of nonabelian dual theories. We show how, in the case with vanishing isotropy, it…

High Energy Physics - Theory · Physics 2009-10-22 Amit Giveon , Martin Rocek

We introduce a topology on the space of actions modulo weak equivalence finer than the one previously studied in the literature. We show that the product of actions is a continuous operation with respect to this topology, so that the space…

Dynamical Systems · Mathematics 2015-01-26 Peter Burton

We construct countable groups $G$ with the following new degree of W*-superrigidity: if $L(G)$ is virtually isomorphic, in the sense of admitting a bifinite bimodule, with any other group von Neumann algebra $L(\Lambda)$, then the groups…

Operator Algebras · Mathematics 2025-03-14 Milan Donvil , Stefaan Vaes

We obtain a Halmos-Richter-type wandering subspace theorem for covariant representations of C*-correspondences. Further the notion of Cauchy dual and a version of Shimorin's Wold-type decomposition for covariant representations of…

Operator Algebras · Mathematics 2021-06-01 Harsh Trivedi , Shankar Veerabathiran

We classify conjugacy classes of involutions in the isometry groups of nondegenerate, symmetric bilinear forms over the field of two elements. The new component of this work focuses on the case of an orthogonal form on an even dimensional…

Group Theory · Mathematics 2016-12-28 Daniel Dugger

We consider discontinuous operations of a group $G$ on a contractible $n$-dimensional manifold $X$. Let $E$ be a finite dimensional representation of $G$ over a field $k$ of characteristics 0. Let $\mathcal{E}$ be the sheaf on the quotient…

Algebraic Topology · Mathematics 2009-01-19 F. Grunewald , W. Singhof

It is well known that if two finite groups have the same symmetric tensor categories of representations over C, then they are isomorphic. We study the following question: when do two finite groups G1,G2 have the same tensor categories of…

Quantum Algebra · Mathematics 2007-05-23 Pavel Etingof , Shlomo Gelaki

We study algebraic varieties parametrized by topological spaces and enlarge the domains of Lawson homology and morphic cohomology to this category. We prove a Lawson suspension theorem and splitting theorem. A version of Friedlander-Lawson…

Algebraic Geometry · Mathematics 2012-01-04 J. H. Teh

In this paper, we consider an equivalence relation within the class of finitely presented discrete groups attending to their asymptotic topology rather than their asymptotic geometry. More precisely, we say that two finitely presented…

Geometric Topology · Mathematics 2020-02-05 M. Cárdenas , F. F. Lasheras , A. Quintero , R. Roy

We prove that if $G$ is finite 2-generated $p$-group of nilpotence class at most 2 then the group algebra of $G$ with coefficients in the field with $p$ elements determines $G$ up to isomorphisms.

Group Theory · Mathematics 2020-04-07 Osnel Broche , Ángel del Río

In this semi-expository note, we give a new proof of a structure theorem due to Shimura for nearly holomorphic modular forms on the complex upper half plane. Roughly speaking, the theorem says that the space of all nearly holomorphic…

Number Theory · Mathematics 2015-01-06 Ameya Pitale , Abhishek Saha , Ralf Schmidt

We explain why on certain five-manifolds, topological 5d $\mathcal{N} = 2$ gauge theory of Haydys-Witten twist with gauge group $G$, is dual to that of Geyer-M\"{u}lsch twist with gauge group $^LG$, where $G$ is a real, compact Lie group…

High Energy Physics - Theory · Physics 2026-03-27 Arif Er , Meng-Chwan Tan

The Exel-Loring formula asserts that two topological invariants associated to a pair of almost commuting unitary matrices coincide. Such a pair can be viewed as a quasi-representation of $\mathbb{Z}^2$. We give a generalization of this…

Operator Algebras · Mathematics 2022-04-20 Marius Dadarlat

We introduce a notion of $Q$-algebra that can be considered as a generalization of the notion of $Q$-manifold (a supermanifold equipped with an odd vector field obeying $\{Q,Q\} =0$). We develop the theory of connections on modules over…

High Energy Physics - Theory · Physics 2009-11-07 Albert Schwarz

The second author introduced notions of weak permutability and commutativity between groups and proved the finiteness of a group generated by two weakly permutable finite groups. Two groups H,K weakly commute provided there exists a…

Group Theory · Mathematics 2009-06-29 Ricardo N. Oliveira , Said N. Sidki

We show how to implement T-duality along non-abelian isometries in backgrounds with non-vanishing Ramond fields. When the dimension of the isometry group is odd (even) the duality swaps (preserves) the chirality of the theory. In certain…

High Energy Physics - Theory · Physics 2011-02-03 Konstadinos Sfetsos , Daniel C. Thompson

We explain an elementary topological construction of the Springer representation on the homology of (topological) Springer fibers of types C and D in the case of nilpotent endomorphisms with two Jordan blocks. The Weyl group and component…

Representation Theory · Mathematics 2021-10-26 Catharina Stroppel , Arik Wilbert

We introduce a notion called `maximal commuting piece' for tuples of Hilbert space operators. Given a commuting tuple of operators forming a row contraction there are two commonly used dilations in multivariable operator theory. Firstly…

Operator Algebras · Mathematics 2014-05-16 B. V. Rajarama Bhat , Tirthankar Bhattacharyya , Santanu Dey

Working in the context of symmetric spectra, we describe and study a homotopy completion tower for algebras and left modules over operads in the category of modules over a commutative ring spectrum (e.g., structured ring spectra). We prove…

Algebraic Topology · Mathematics 2014-11-11 John E. Harper , Kathryn Hess

This paper investigates the interplay between algebraic structure, topology, and differentiability in Clifford semigroups. The study is developed along three main themes. First, in the compact Hausdorff setting, we provide an explicit…

General Topology · Mathematics 2026-04-28 Stefano Bonzio , Andrea Loi , Giuseppe Zecchini