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We describe absolutely ordered $p$-normed spaces, for $1 \le p \le \infty$ which presents a model for "non-commutative" vector lattices and includes order theoretic orthogonality. To demonstrate its relevance, we introduce the notion of…

Functional Analysis · Mathematics 2017-12-19 Anil Kumar Karn

It is shown that a trace invariant projection map, i.e. a positive unital idempotent map, of a finite dimensional C*-algebra into itself is non-decomposable if and only if it is atomic, or equivalently not the sum of a 2-positive and a…

Operator Algebras · Mathematics 2009-04-02 Erling Stormer

While there has been growing interest for noncommutative spaces in recent times, most examples have been based on the simplest noncommutative algebra: [x_i,x_j]=i theta_{ij}. Here we present new classes of (non-formal) deformed products…

High Energy Physics - Theory · Physics 2009-11-07 J. M. Gracia-Bondia , F. Lizzi , G. Marmo , P. Vitale

Let $w$ be a Muckenhoupt $A_2(\mathbb{R}^n)$ weight and $L_w:=-w^{-1}\mathop\mathrm{div}(A\nabla)$ the degenerate elliptic operator on the Euclidean space $\mathbb{R}^n$. In this article, the authors establish the Riesz transform…

Classical Analysis and ODEs · Mathematics 2015-09-21 Dachun Yang , Junqiang Zhang

This paper uses Brin and Thickstun's theory of end reductions of non-compact 3-manifolds to study groups of covering translations of irreducible contractible open 3-manifolds W which are not homeomorphic to R^3. We associate to W an object…

Geometric Topology · Mathematics 2007-05-23 Robert Myers

The classical commutative coding theory has been recently extended to noncommutative rings of polynomial type. There are many interesting works in coding theory over single Ore extensions. In this review article we present the most relevant…

Rings and Algebras · Mathematics 2023-11-01 Oswaldo Lezama , Claudia Gallego

Regularity and irregularity of the Bergman projection on $L^p$ spaces is established on a natural family of bounded, pseudoconvex domains. The family is parameterized by a real variable $\gamma$. A surprising consequence of the analysis is…

Complex Variables · Mathematics 2017-12-27 L. D. Edholm , J. D. McNeal

We investigate the decomposability of nonnegative compact r-potent operators on a separable Hilbert space L2(X). We provide a constructive algorithm to prove that basis functions of range spaces of nonnegative r-potent operators can be…

Functional Analysis · Mathematics 2015-04-20 Rashmi Sehgal Thukral , Alka Marwaha

We give complete characterisation of topologically injective (bounded below), topologically surjective (open mapping), isometric and coisometric (quotient mapping) multiplication operators between $L_p$ spaces defined on different…

Functional Analysis · Mathematics 2013-09-20 Norbert Nemesh

We define norms on $L_p(\mathcal{M}) \otimes M_n$ where $\mathcal{M}$ is a von Neumann algebra and $M_n$ is the complex $n \times n$ matrices. We show that a linear map $T: L_p(\mathcal{M}) \to L_q(\mathcal{N})$ is decomposable if…

Operator Algebras · Mathematics 2020-03-24 Erwin Neuhardt

If $\Omega$ is a measure space, we show that absolute contractions which are selfadjoint on $\mathrm{L}^2(\Omega)$ induce contractions on $\mathrm{L}^p(\Omega)$ which satisfy the Blum-Hanson property. Our very short argument relies on the…

Functional Analysis · Mathematics 2022-03-24 Cédric Arhancet

A commuting triple of Hilbert space operators $(A,B,P)$, for which the closed tetrablock $\overline{\mathbb E}$ is a spectral set, is called a \textit{tetrablock-contraction} or simply an $\mathbb E$-\textit{contraction}, where \[ \mathbb…

Functional Analysis · Mathematics 2022-05-31 Sourav Pal

We construct a family of self-adjoint operators D_N which have compact resolvent and bounded commutators with the coordinate algebra of the quantum projective space CP_q(l), for any l>1 and 0<q<1. They provide 0^+ dimensional equivariant…

Quantum Algebra · Mathematics 2010-06-01 Francesco D'Andrea , Ludwik Dabrowski

We construct several $C^*$-algebras and spectral triples associated to the Berkovich projective line $\mathbb{P}^1_{\mathrm{Berk}}({\mathbb{C}_p})$. In the commutative setting, we construct a spectral triple as a direct limit over finite…

Functional Analysis · Mathematics 2026-04-10 Masoud Khalkhali , Damien Tageddine

The article proves an assertion analogous to the Littlewood-Paley theorem for the orthoprojectors onto mutually orthogonal subspaces of piecewise polynomial functions on the cube $ I^d. $ This assertion provides an upper estimate for the…

Classical Analysis and ODEs · Mathematics 2011-11-28 S. N. Kudryavtsev

We complete the $L^p$ boundedness theory of commutators of Hilbert transforms along monomial curves by providing the previously missing lower bounds. This optimal result now covers all monomial curves while previous results had significant…

Classical Analysis and ODEs · Mathematics 2024-03-14 Kangwei Li , Henri Martikainen , Tuomas Oikari

We investigate the most general non(anti)commutative geometry in N=1 four-dimensional superspace, invariant under the classical (i.e., undeformed) supertranslation group. We find that a nontrivial non(anti)commutative superspace geometry…

High Energy Physics - Theory · Physics 2009-11-07 Dietmar Klemm , Silvia Penati , Laura Tamassia

We study the non-wandering set of $C^3$ contracting Lorenz maps $f$ with negative Schwarzian derivative. We show that if $f$ doesn't have attracting periodic orbit, then there is a unique topological attractor. Precisely, there is a…

Dynamical Systems · Mathematics 2014-02-13 Paulo Brandão

In this talk, based on work done in collaboration with G. Landi and R.J Szabo, I will review how string theory can be considered as a noncommutative geometry based on an algebra of vertex operators. The spectral triple of strings is…

High Energy Physics - Theory · Physics 2011-04-15 Fedele Lizzi

We show that a non-commutative structure arises naturally from perturbative quantum gravity in a de Sitter background metric. Our work builds on recent advances in the construction of observables in highly symmetric background spacetimes…

General Relativity and Quantum Cosmology · Physics 2023-10-10 Markus Fröb , William C. C. Lima , Albert Much , Kyriakos Papadopoulos