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Related papers: Direct integrals and spectral averaging

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In this work, a connection between some spectral properties of direct integral of operators in the direct integral of Hilbert spaces and their coordinate operators has been investigated.

Functional Analysis · Mathematics 2011-12-13 Z. I. Ismailov , E. Otkun Cevik

Joint spectra of tuples of operators are subsets in complex projective space. The corresponding tuple of operators can be viewed as an infinite dimensional analog of a determinantal representation of the joint spectrum. We investigate the…

Spectral Theory · Mathematics 2015-09-22 Michael Stessin , Alexandre Tchernev

Discovered by M.G.Krein analogy between polinomials orthogonal on the unit circle and generalized eigenfunctions of certain differential systems is used to obtain some new results in the spectral analysis of Sturm-Liouville operators. Some…

Mathematical Physics · Physics 2007-05-23 S. A. Denisov

This work provides an introduction and overview on some basic mathematical aspects of the single-flux Aharonov-Bohm Schr\"odinger operator. The whole family of admissible self-adjoint realizations is characterized by means of four different…

Mathematical Physics · Physics 2024-07-23 Davide Fermi

First order integro-differential operators on a finite interval are studied. Properties of spectral characteristic are established, and the uniqueness theorem is proved for the inverse problem of recovering operators from their spectral…

Spectral Theory · Mathematics 2017-05-17 Vjacheslav Yurko

We expose a functional integration method for the averaging of continuous products $\hat{P}_t$ of $N\times N$ random matrices. As an application, we compute exactly the statistics of the Lyapunov spectrum of $\hat{P}_t$. This problem is…

Disordered Systems and Neural Networks · Physics 2009-10-28 A. Gamba , I. V. Kolokolov

This article presents a new proof of a theorem concerning bounds of the spectrum of the product of unitary operators and a generalization for differentiable curves of this theorem. The proofs involve metric geometric arguments in the group…

Functional Analysis · Mathematics 2023-11-03 Martin Miglioli

This paper is concerned with a certain aspect of the spectral theory of unitary operators in a Hilbert space and its aim is to give an explicit construction of continuous functions of unitary operators. Starting from a given unitary…

Functional Analysis · Mathematics 2014-03-11 Krzysztof Zajkowski

This work aims to bridge the gap between pure and applied research on scalar, linear Volterra equations by examining five major classes: integral and integro-differential equations with completely monotone kernels, such as linear…

Classical Analysis and ODEs · Mathematics 2026-01-09 David Darrow , George Stepaniants

We describe spectra of associative (not necessarily unital and not necessarily countable-dimensional) locally matrix algebras. We determine all possible spectra of locally matrix algebras and give a new proof of Dixmier-Baranov Theorem. As…

Rings and Algebras · Mathematics 2020-11-18 Oksana Bezushchak

We perform certain alternating binomial summations with parameters that occur in the analysis of algorithms. A combination of integral and special function and special number representations is used. The results are sufficiently general to…

Mathematical Physics · Physics 2007-05-23 Mark W. Coffey

In this paper, we establish a $q$-integral formula by using the orthogonality relation, and also provide a new proof of the $q$-orthogonality relation for the continuous $q$-ultraspherical polynomials. A new $q$-beta integral with five…

Classical Analysis and ODEs · Mathematics 2024-08-09 Dandan Chen , Zhiguo Liu

This work develops an analytic framework for the study of the $\zeta$-function associated with general sequences of complex numbers. We show that a contour integral representation, commonly used when studying spectral $\zeta$-functions…

Classical Analysis and ODEs · Mathematics 2025-08-22 Guglielmo Fucci , Mateusz Piorkowski , Jonathan Stanfill

Dyson's integration theorem is widely used in the computation of eigenvalue correlation functions in Random Matrix Theory. Here we focus on the variant of the theorem for determinants, relevant for the unitary ensembles with Dyson index…

Mathematical Physics · Physics 2008-11-26 Gernot Akemann , Leonid Shifrin

Let $L$ be a non-negative self adjoint operator acting on $L^2(X)$ where $X$ is a space of homogeneous type. Assume that $L$ generates a holomorphic semigroup $e^{-tL}$ whose kernels $p_t(x,y)$ satisfy generalized $m$-th order Gaussian…

Analysis of PDEs · Mathematics 2012-11-07 Adam Sikora , Lixin Yan , Xiaohua Yao

This is the second part of a work dedicated to the study of Bernstein-Sato polynomials for several analytic functions depending on parameters. In this part, we give constructive results generalizing previous ones obtained by the author in…

Algebraic Geometry · Mathematics 2007-05-23 Rouchdi Bahloul

We prove new upper bounds for a spectral exponential sum by refining the process by which one evaluates mean values of $L$-functions multiplied by an oscillating function. In particular, we introduce a method which is capable of taking into…

Number Theory · Mathematics 2018-09-19 Olga Balkanova , Dmitry Frolenkov

We consider stochastic differential equations, obtained by adding weak Gaussian white noise to ordinary differential equations admitting $N$ asymptotically stable periodic orbits. We construct a discrete-time, continuous-space Markov chain,…

Probability · Mathematics 2017-11-06 Manon Baudel , Nils Berglund

This paper addresses two different but related questions regarding an unbounded symmetric tridiagonal operator: its self-adjointness and the approximation of its spectrum by the eigenvalues of its finite truncations. The sufficient…

Functional Analysis · Mathematics 2014-07-17 Eugenia N. Petropoulou , L. Velázquez

We study the spectrum of one dimensional integral operators in bounded real intervals of length $2L$, for value of $L$ large. The integral operators are obtained by linearizing a non local evolution equation for a non conserved order…

Mathematical Physics · Physics 2017-01-16 Enza Orlandi , Carlangelo Liverani