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Permutation invariant polynomial functions of matrices have previously been studied as the observables in matrix models invariant under $S_N$, the symmetric group of all permutations of $N$ objects. In this paper, the permutation invariant…

High Energy Physics - Theory · Physics 2022-08-24 George Barnes , Adrian Padellaro , Sanjaye Ramgoolam

We consider cyclic $m$-isometries on a complex separable Hilbert space. Such operators are characterized in terms of shifts on abstract spaces of weighted Dirichlet type. Our results resemble those of Agler and Stankus, but our model spaces…

Functional Analysis · Mathematics 2018-12-05 Eskil Rydhe

Let $B_n$ denote the unit ball of $\mathbb{C}^n$, $n\ge 1$, and let $\mathcal{D}$ denote a finite product of $B_{n_j}$, $j\ge 1$. Given a non-constant holomorphic function $b: \mathcal{D} \to B_1$, we study the corresponding family…

Complex Variables · Mathematics 2021-08-20 Aleksei B. Aleksandrov , Evgueni Doubtsov

We study the relationship between sampling sequences in infinite dimensional Hilbert spaces of analytic functions and Marcinkiewicz-Zygmund inequalities in subspaces of polynomials. We focus on the study of the Hardy space and the Bergman…

Complex Variables · Mathematics 2023-04-18 Karlheinz Gröchenig , Joaquim Ortega-Cerdà

Let $M$ be a commutative homogeneous space of a compact Lie group $G$ and $A$ be a closed $G$-invariant subalgebra of the Banach algebra $C(M)$. A function algebra is called antisymmetric if it does not contain nonconstant real functions.…

Functional Analysis · Mathematics 2009-07-17 V. M. Gichev

We prove the boundedness of Bergman type projections in two different analytic function spaces in bounded strongly pseudoconvex domains with the smooth boundary. Our results were previously well-known in the case of the unit disk.

Complex Variables · Mathematics 2025-08-28 R. F. Shamoyan , E. B. Tomashevskaya

If $\mu $ is a positive Borel measure on the interval $[0, 1)$ we let $\mathcal H_\mu $ be the Hankel matrix $\mathcal H_\mu =(\mu_{n, k})_{n,k\ge 0}$ with entries $\mu_{n, k}=\mu_{n+k}$, where, for $n\,=\,0, 1, 2, \dots $, $\mu_n$ denotes…

Complex Variables · Mathematics 2018-05-23 Daniel Girela , Noel Merchán

For a (not necessarily locally convex) topological vector space $\mathcal{X}$ of holomorphic functions in one complex variable, we show that the shift invariant subspace generated by a set of polynomials is $\mathcal{X}$ if and only if…

Complex Variables · Mathematics 2025-12-02 Mikhail Mironov , Jeet Sampat

Some concepts, such as non-compactness measure and condensing operators, defined on metric spaces are extended to uniform spaces. Such extensions allow us to locate, in the context of uniform spaces, some classical results existing in…

General Topology · Mathematics 2015-11-25 Raúl Fierro

We characterize the Carleson measures $\mu$ on the unit disk for which the image of the Hardy space $H^p$ under the corresponding embedding operator is closed in $L^p(\mu)$. In fact, a more general result involving $(p,q)$-Carleson measures…

Complex Variables · Mathematics 2026-04-01 Konstantin M. Dyakonov

We obtain general identities for the product of two Schur functions in the case where one of the functions is indexed by a rectangular partition, and give their t-analogs using vertex operators. We study subspaces forming a filtration for…

Combinatorics · Mathematics 2007-05-23 L. Lapointe , J. Morse

For a given Beurling-Carleson subset $E$ of the unit circle $\mathbb{T}$ which has positive Lebesgue measure, we give explicit formulas for measurable functions supported on $E$ such that their Cauchy transforms have smooth extensions from…

Functional Analysis · Mathematics 2022-05-06 Adem Limani , Bartosz Malman

Motivated by an influential result of Bourgain and Tzafriri, we consider continuous matrix functions $A:\mathbb{R}\to M_{n\times n}$ and lower $\ell_2$-norm bounds associated with their restriction to certain subspaces. We prove that for…

Functional Analysis · Mathematics 2022-01-14 Adrian Fan , Jack Montemurro , Pavlos Motakis , Naina Praveen , Alyssa Rusonik , Paul Skoufranis , Noam Tobin

We study closed subspaces of $L^2(X)$, where $(X, \mu)$ is a $\sigma$-finite measure space, that are invariant under the unitary representation associated to a measurable action of a discrete countable LCA group $\Gamma$ on $X$. We provide…

Functional Analysis · Mathematics 2015-06-22 Davide Barbieri , Eugenio Hernández , Victoria Paternostro

The objective of this paper is to study wandering subspaces for commuting tuples of bounded operators on Hilbert spaces. It is shown that, for a large class of analytic functional Hilbert spaces $\mathcal{H}_K$ on the unit ball in $\mathbb…

Functional Analysis · Mathematics 2016-10-19 M. Bhattacharjee , J. Eschmeier , Dinesh K. Keshari , Jaydeb Sarkar

We investigate the non-univalent function's properties reminiscent of the theory of univalent starlike functions. Let the analytic function $\psi(z)=\sum_{i=1}^{\infty}A_i z^i$, $A_1\neq0$ be univalent in the unit disk. Non-univalent…

Complex Variables · Mathematics 2022-08-02 Kamaljeet Gangania

Let P -> M be a principal G-bundle. Using techniques from the loop representation of gauge theory, we construct well-defined substitutes for ``Lebesgue measure'' on the space A of connections on P and for ``Haar measure'' on the group Ga of…

High Energy Physics - Theory · Physics 2009-10-22 John C. Baez

We examine some alternative possibilities for an action functional for $\kappa$-Minkowski noncommutative spacetime, with an approach which should be applicable to other spacetimes with coordinate-dependent commutators of the spacetime…

High Energy Physics - Theory · Physics 2007-05-23 Alessandra Agostini , Giovanni Amelino-Camelia , Michele Arzano , Francesco D'Andrea

The super Weil-Petersson metric defined over the moduli space of smooth super curves produces a natural measure over the moduli space of smooth curves. The construction of the measure uses the extra data of a spin structure on each smooth…

Algebraic Geometry · Mathematics 2024-11-04 Paul Norbury

Let $\mathbb H$ be the finite direct sums of $H^2(\mathbb D)$. In this paper, we give a characterization of the closed subspaces of $\mathbb H$ which are invariant under the shift, thus obtaining a concrete Beurling-type theorem for the…

Functional Analysis · Mathematics 2026-02-17 Filippo Bracci , Eva A. Gallardo-Gutiérrez