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Let $V$ be a two-dimensional vector space over a field $\mathbb F$ of characteristic not $2$ or $3$. We show there is a canonical surjection $\nu$ from the set of suitably generic commutative algebra structures on $V$ modulo the action of…

Commutative Algebra · Mathematics 2016-12-20 M. Rausch de Traubenberg , M. Slupinski

For locally compact groups G and H let A(G) denote the Fourier algebra of G and B(H) the Fourier-Stieltjes algebra of H. Any continuous piecewise affine map alpha:Y -> G (where Y is an element of the open coset ring of H) induces a…

Functional Analysis · Mathematics 2007-05-23 M. Ilie , N. Spronk

The classical decomposition theory for states on a C*-algebra that are invariant under a group action has been studied by using the theory of orthogonal measures on the state space \cite{BR1}. In \cite{BK3}, we introduced the notion of…

Operator Algebras · Mathematics 2024-09-05 Angshuman Bhattacharya , Chaitanya J. Kulkarni

Let $W$ be a finite-dimensional representation of a reductive algebraic group $G$. The invariant Hilbert scheme $\mathcal{H}$ is a moduli space that classifies the $G$-stable closed subschemes $Z$ of $W$ such that the affine algebra $k[Z]$…

Algebraic Geometry · Mathematics 2014-01-21 Ronan Terpereau

We prove that local stable/unstable sets of homeomorphisms of an infinite compact metric space satisfying the gluing-orbit property always contain compact and perfect subsets of the space. As a consequence, we prove that if a positively…

Dynamical Systems · Mathematics 2024-05-30 Mayara Antunes , Bernardo Carvalho , Welington Cordeiro , José Cueto

For a sequence of extrinsic or intrinsic biharmonic maps $u_j: M_j\rightarrow N$ from a sequence of non-collapsed degenerating closed Einstein 4-manifolds $(M_j,g_j)$ with bounded Einstein constants, bounded diameters and bounded $L^2$…

Differential Geometry · Mathematics 2021-04-20 Youmin Chen , Miaomiao Zhu

The primary aim of this paper is to characterize the uniformly locally univalent harmonic mappings in the unit disk. Then, we obtain sharp distortion, growth and covering theorems for one parameter family ${\mathcal B}_{H}(\lambda)$ of…

Complex Variables · Mathematics 2016-01-07 S. Ponnusamy , J. Qiao , X. Wang

The author reviews his results on locally compact homogeneous spaces with inner metric, in particular, homogeneous manifolds with inner metric. The latter are isometric to homogeneous (sub-)Finslerian manifolds; under some additional…

Differential Geometry · Mathematics 2014-12-30 V. N. Berestovskii

Let $G$ be a real linear reductive group and let $H$ be a unimodular, locally algebraic subgroup. Let $\operatorname{supp} L^2(G/H)$ be the set of irreducible unitary representations of $G$ contributing to the decomposition of $L^2(G/H)$,…

Representation Theory · Mathematics 2026-01-08 Benjamin Harris , Yoshiki Oshima

We will consider completely positive maps defined on tensor products of von Neumann algebras and taking values in the algebra of bounded operators on a Hilbert space and particularly certain convex subsets of the set of such maps. We show…

Quantum Physics · Physics 2014-03-21 Erkka Haapasalo , Teiko Heinosaari , Juha-Pekka Pellonpää

We introduce quantum tomography on locally compact Abelian groups $G$. A linear map from the set of quantum states on the $C^*$-algebra $A(G)$ generated by the projective unitary representation of $G$ to the space of characteristic…

Quantum Physics · Physics 2022-05-26 Grigori Amosov

We consider \Gamma-equivariant principal G-bundles over proper \Gamma-CW-complexes with prescribed family of local representations. We construct and analyze their classifying spaces for locally compact, second countable topological groups…

Algebraic Topology · Mathematics 2014-11-11 Bernardo Uribe , Wolfgang Lueck

We study the structure of invariant measures for continuous automorphisms of compact metrizable abelian groups satisfying the descending chain condition. We show that the finitely supported invariant measures are weak-* dense in the space…

Dynamical Systems · Mathematics 2025-07-21 Rotem Yaari

Let $\phi: G \rightarrow H$ be a group homomorphism such that $H$ is a totally disconnected locally compact (t.d.l.c.) group and the image of $\phi$ is dense. We show that all such homomorphisms arise as completions of $G$ with respect to…

Group Theory · Mathematics 2018-01-04 Colin D. Reid , Phillip R. Wesolek

Let $S$ be a projective simply connected complex surface and $\mathcal{L}$ be a line bundle on $S$. We study the moduli space of stable compactly supported 2-dimensional sheaves on the total spaces of $\mathcal{L}$. The moduli space admits…

Algebraic Geometry · Mathematics 2020-04-13 Amin Gholampour , Artan Sheshmani , Shing-Tung Yau

Let $K$ be a field and let $R$ be a regular domain containing $K$. Let $G$ be a finite subgroup of the group of automorphisms of $R$. We assume that $|G|$ is invertible in $K$. Let $R^G$ be the ring of invariants of $G$. Let $I$ be an ideal…

Commutative Algebra · Mathematics 2019-02-20 Tony J. Puthenpurakal

Let $G$ be a locally compact abelian topological group. For locally bounded measurable functions $\varphi: G\to\Bbb {C}$ we discuss notions of spectra for $\varphi$ relative to subalgebras of $L^{1}(G)$. In particular we study polynomials…

Functional Analysis · Mathematics 2013-06-05 B. Basit , A. J. Pryde

Let G be a locally compact Hausdorff group in which every element is of finite order, and let P(G) denote the class of all regular probability measures on G. In this note, it is observed that a characterization of algebraically regular…

Functional Analysis · Mathematics 2026-03-20 M N N Namboodiri

In this paper, we investigate structural properties of finite groups that are detected by certain group invariants arising from Dijkgraaf--Witten theory, a topological quantum field theory, in one space and one time dimension. In this…

Group Theory · Mathematics 2026-04-28 Christopher A. Schroeder , Hung P. Tong-Viet

For any open, connected and bounded set $\Omega \subseteq \mathbb C^m$, let $\mathcal A$ be a natural function algebra consisting of functions holomorphic on $\Omega$. Let $\mathcal M$ be a Hilbert module over the algebra $\mathcal A$ and…

Functional Analysis · Mathematics 2007-05-23 Ronald G. Douglas , Gadadhar Misra