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Related papers: The spectral flow, the Fredholm index, and the spe…

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We examine the spectrum of a family of Sturm--Liouville operators with regularly spaced delta function potentials parametrized by increasing strength. The limiting behavior of the eigenvalues under this spectral flow was described in a…

Spectral Theory · Mathematics 2020-06-25 Thomas Beck , Isabel Bors , Grace Conte , Graham Cox , Jeremy L. Marzuola

A new derivative, called deformable derivative, is introduced here which is equivalent to ordinary derivative in the sense that one implies other. The deformable derivative is defined using limit approach like that of ordinary one but with…

Classical Analysis and ODEs · Mathematics 2017-05-03 Fahed Zulfeqarr , Amit Ujlayan , Priyanka Ahuja

Graph signal processing is an emerging field which aims to model processes that exist on the nodes of a network and are explained through diffusion over this structure. Graph signal processing works have heretofore assumed knowledge of the…

Signal Processing · Electrical Eng. & Systems 2021-04-21 Matthew W. Morency , Geert Leus

We extend the relative index theorem on non-compact manifolds to encompass a wide variety of hypoelliptic differential operators of arbitrary order, demonstrating that the change in index when changing a differential operator locally can be…

K-Theory and Homology · Mathematics 2025-11-11 Magnus Fries

We show that every separable Gaussian process with integrable variance function admits a Fredholm representation with respect to a Brownian motion. We extend the Fredholm representation to a transfer principle and develop stochastic…

Probability · Mathematics 2016-03-23 Tommi Sottinen , Lauri Viitasaari

The paper deals with first order self-adjoint elliptic differential operators on a smooth compact oriented surface with non-empty boundary. We consider such operators with self-adjoint local boundary conditions. The paper is focused on…

Analysis of PDEs · Mathematics 2023-02-01 Marina Prokhorova

This is a reference volume on polyfold and Fredholm theory.

Functional Analysis · Mathematics 2017-07-28 Helmut Hofer , Krzysztof Wysocki , Eduard Zehnder

This paper expresses the Chern character for topological K-theory based on the formulation of the family of Fredholm operators, by using the points at which the Fredholm operator becomes singular (Fermi points). In particular, we explain…

K-Theory and Homology · Mathematics 2026-03-11 Kyouhei Horie

In this Thesis, we study the behavior of spectral curves of quantum graphs under certain families of vertex conditions, called the $\delta_s$ family, which we define in this work. We focus on studying two main quantities related to the…

Mathematical Physics · Physics 2023-01-30 Gilad Sofer

We study a nonlocal diffusion operator in a bounded smooth domain prescribing the flux through the boundary. This problem may be seen as a generalization of the usual Neumann problem for the heat equation. First, we prove existence,…

Analysis of PDEs · Mathematics 2007-05-23 C. Cortazar , M. Elgueta , J. D. Rossi , N. Wolanski

For the pair $\{-\Delta, -\Delta-\alpha\delta_\mathcal{C}\}$ of self-adjoint Schr\"{o}dinger operators in $L^2(\mathbb{R}^n)$ a spectral shift function is determined in an explicit form with the help of (energy parameter dependent)…

Spectral Theory · Mathematics 2017-10-11 Jussi Behrndt , Fritz Gesztesy , Shu Nakamura

We give upper and lower bounds on the spectral radius of a graph in terms of the number of walks. We generalize a number of known results.

Combinatorics · Mathematics 2007-05-23 Vladimir Nikiforov

Spectrotemporal encoding of optical quantum information is emerging as a powerful tool in quantum information technology. Processing of spectrotemporal information has recently been demonstrated in multi-mode quantum memories, based on…

Quantum Physics · Physics 2025-11-19 Jesse L Everett

In this article, we determine the multivariate multifractal Legendre spectra of shifted L{\'e}vy functions. This allows us to explore how the validity of the multivariate multifractal formalism depends on the shift parameter. This article…

Dynamical Systems · Mathematics 2025-05-15 Stéphane Jaffard , Lingmin Liao , Qian Zhang

Another way to evaluate the spectral-correlation properties of thermal fields of solids is suggested. Such a method takes into account detailed structure of the interface transition layer separating one bulk region from those of the vacuum…

Quantum Physics · Physics 2015-06-15 Illarion Dorofeyev

This paper determines how to define a discretely implemented Fourier transform when analysing an observed spatial point process. To develop this transform we answer four questions; first what is the natural definition of a Fourier…

Methodology · Statistics 2023-06-08 Tuomas A. Rajala , Sofia C. Olhede , Jake P. Grainger , David J. Murrell

In the first part of the article we establish the existence in the sense of sequences of solutions in $H^{2}(R)$ for some nonhomogeneous linear differential equation in which one of the terms has the argument translated by a constant. It is…

Analysis of PDEs · Mathematics 2026-01-01 Vitali Vougalter , Vitaly Volpert

In this paper, we introduce the concept of the $\alpha$-fractal function and fractal approximation for a set-valued continuous map defined on a closed and bounded interval of real numbers. Also, we study some properties of such fractal…

Functional Analysis · Mathematics 2022-07-07 Megha Pandey , Tanmoy Som , Saurabh Verma

In this paper we study the semi-Fredholm property of band-dominated operators $A$ and prove that it already implies the Fredholmness of $A$ in all cases where this is not disqualified by obvious reasons. Moreover, this observation is…

Functional Analysis · Mathematics 2015-11-23 Markus Seidel

The Schr\"odinger equation is considered on the half line with a selfadjoint boundary condition when the potential is real valued, integrable, and has a finite first moment. It is proved that the potential and the two boundary conditions…

Mathematical Physics · Physics 2007-05-23 Tuncay Aktosun , Ricardo Weder