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Related papers: Functional Calculus for Semi-Bounded Operators

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We give a new proof of a characterization of the closeness of the range of a continuous linear operator and of the closeness of the sum of two closed vector subspaces of a Banach space. Then we state sufficient conditions for the closeness…

Functional Analysis · Mathematics 2015-10-06 Joël Blot , Philippe Cieutat

We prove that the existence of a Mihlin-H\"ormander functional calculus for an operator $L$ implies the boundedness on $L^p$ of both the maximal operators and the continuous square functions build on spectral multipliers of $L.$ The…

Functional Analysis · Mathematics 2016-08-08 Błażej Wróbel

In this work we prove a new $L^p$ holomorphic extension result for functions defined on product Lipschitz surfaces with small Lipschitz constants in two complex variables. We define biparameter and partial Cauchy integral operators that…

Classical Analysis and ODEs · Mathematics 2015-04-02 Jarod Hart , Alessandro Monguzzi

We develop a very general operator-valued functional calculus for operators with an $H^{\infty}-$calculus. We then apply this to the joint functional calculus of two commuting sectorial operators when one has an $H^{\infty}$calculus. Using…

Functional Analysis · Mathematics 2007-05-23 N. J. Kalton , L. Weis

Let $X$ be a complex Banach space. The connection between algebra homomorphisms defined on subalgebras of the Banach algebra $\ell^{1}(\mathbb{N}_0)$ and the algebraic structure of Ces\`{a}ro sums of a linear operator $T\in \mathcal{B}(X)$…

Functional Analysis · Mathematics 2015-04-07 Luciano Abadias , Carlos Lizama , Pedro J. Miana , M. Pilar Velasco

We state several equivalent noncommutative versions of the Cauchy-Riemann equations and characterize the unbounded operators on L^2(R) which satisfy them. These operators arise from the creation operator via a functional calculus involving…

Operator Algebras · Mathematics 2007-05-23 Richard Rochberg , Nik Weaver

Spectral theory and functional calculus for unbounded self-adjoint operators on a Hilbert space are usually treated through von Neumann's Cayley transform. Based on ideas of Woronowicz, we redevelop this theory from the point of view of…

Operator Algebras · Mathematics 2016-09-14 Christian Budde , Klaas Landsman

The main purpose of this work is the construction of an analytic functional calculus for Clifford operators, which are operators acting on certain modules over Clifford algebras. Unlike in some preceding works by other authors, we use a…

Functional Analysis · Mathematics 2020-08-18 Florian-Horia Vasilescu

We consider operator-valued Herglotz functions and their applications to self-adjoint perturbations of self-adjoint operators and self-adjoint extensions of densely defined closed symmetric operators. Our applications include model…

Functional Analysis · Mathematics 2007-05-23 Fritz Gesztesy , Nigel J. Kalton , Konstantin A. Makarov , Eduard Tsekanovskii

We give an extension of Rubio de Francia's extrapolation theorem for functions taking values in UMD Banach function spaces to the multilinear limited range setting. In particular we show how boundedness of an $m$-(sub)linear operator…

Classical Analysis and ODEs · Mathematics 2024-05-31 Emiel Lorist , Zoe Nieraeth

For any bounded, regulated function $m: [0,\infty) \to \mathbb{C}$, consider the family of operators $\{ T_R \}$ on the sphere $S^d$ such that $T_R f = m(k/R) f$ for any spherical harmonic $f$ of degree $k$. We completely characterize the…

Classical Analysis and ODEs · Mathematics 2024-11-01 Jacob Denson

This paper investigates when analytic Besov functions of $n$ variables act on the generators of $n$ commuting $C_0$-semigroups on a Banach space. The theory for $n=1$ has already been published, and the present paper uses a different…

Functional Analysis · Mathematics 2024-03-27 Charles Batty , Alexander Gomilko , Dominik Kobos , Yuri Tomilov

In this short note we use ideas from systems theory to define a functional calculus for infinitesimal generators of strongly continuous semigroups on a Hilbert space. Among others, we show how this leads to new proofs of (known) results in…

Functional Analysis · Mathematics 2016-09-29 Felix Schwenninger , Hans Zwart

In the paper is considered two problems on extension of operators whose range space for the first problem (or domain space for the second one) belongs to the fixed class of finite equivalence, which is generated by a given Banach space $X$.…

Functional Analysis · Mathematics 2007-05-23 Eugene Tokarev

We give an elementary proof of weighted resolvent bounds for semiclassical Schr\"odinger operators in dimension two. We require the potential function to be Lipschitz with long range decay. The resolvent norm grows exponentially in the…

Analysis of PDEs · Mathematics 2017-06-06 Jacob Shapiro

The paper provides an explicit description of the structure of the domain of the Friedrichs extension of a second order semibounded elliptic wedge operator, initially defined on smooth functions or sections with compact support away from…

Analysis of PDEs · Mathematics 2015-09-08 Thomas Krainer , Gerardo A. Mendoza

We introduce a modified version of the Whitney extension operators for collections of functions from a closed subset of $\mathbb{R}^n$ into scales of Banach spaces with smoothing operators. We prove an extension theorem for collections…

Functional Analysis · Mathematics 2021-02-12 Pietro Baldi

Let $T\colon X\to X$ be a bounded operator on Banach space, whose spectrum $\sigma(T)$ is included in the closed unit disc $\overline{\mathbb D}$. Assume that the peripheral spectrum $\sigma(T)\cap{\mathbb T}$ is finite and that $T$…

Functional Analysis · Mathematics 2025-02-05 Oualid Bouabdillah , Christian Le Merdy

In this paper, we study spaceability of subsets of generalized Orlicz and Lebesgue spaces associated to Banach function space. Also, we give some sufficient conditions for spaceability of subsets of a general Banach space which improves an…

Functional Analysis · Mathematics 2022-08-09 Alireza Bagheri Salec , Stefan Ivkovic , Seyyed Mohammad Tabatabaie

We consider the action of finitely truncated singular integral operators on functions taking values in a Banach space. Such operators are bounded for any Banach space, but we show a quantitative improvement over the trivial bound in any…

Functional Analysis · Mathematics 2023-10-16 Tuomas Hytönen
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