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Spectral properties of bounded linear operators play a crucial role in several areas of mathematics and physics. For each self-adjoint, trace-class operator $O$ we define a set $\Lambda_n\subset \mathbb{R}$, and we show that it converges to…

Quantum Physics · Physics 2025-10-03 Richárd Balka , Gábor Homa , András Csordás

In this paper, we study the spectral theory for nonlocal dispersal operators with time periodic indefinite weight functions subject to Dirichlet type, Neumann type and spatial periodic type boundary conditions. We first obtain necessary and…

Dynamical Systems · Mathematics 2016-03-01 Wenxian Shen , Xiaoxia Xie

A new geometric proof of the spectral theorem for unbounded self-adjoint operators A in a Hilbert space H is given based on a splitting of A in positive and negative parts A+ and A-. For both operators A+ and A- the spectral family can be…

Functional Analysis · Mathematics 2017-12-22 Herbert Leinfelder

A central feature of quantum mechanics is the non-commutativity of operators used to describe physical observables. In this article, we present a critical analysis on the role of non-commutativity in quantum theory, focusing on its…

Quantum Physics · Physics 2018-03-20 Luca Curcuraci

We prove a HVZ theorem for a general class of no-pair Hamiltonians describing an atom or positively charged ion with several electrons in the presence of a classical external magnetic field. Moreover, we show that there exist infinitely…

Mathematical Physics · Physics 2010-10-11 Oliver Matte , Edgardo Stockmeyer

In this paper we begin a study of the space of unbounded self-adjoint Fredholm operators as a classifying space for K^{1}(X), with the goal of incorporating the information in the eigenspaces and eigenvalues of the operators. In particular,…

K-Theory and Homology · Mathematics 2008-05-31 Ronald G. Douglas , Jerome Kaminker

The nonparametric estimation of the volatility and the drift coefficient of a scalar diffusion is studied when the process is observed at random time points. The constructed estimator generalizes the spectral method by Gobet, Hoffmann and…

Statistics Theory · Mathematics 2017-10-12 Jakub Chorowski , Mathias Trabs

We prove the Ehrenfest theorem of quantum mechanics under sharp assumptions on the operators involved.

Functional Analysis · Mathematics 2010-03-18 Gero Friesecke , Bernd Schmidt

By a series of simple examples, we illustrate how the lack of mathematical concern can readily lead to surprising mathematical contradictions in wave mechanics. The basic mathematical notions allowing for a precise formulation of the theory…

Quantum Physics · Physics 2009-10-31 F. Gieres

We develop an analog of classical oscillation theory for Sturm-Liouville operators which, rather than measuring the spectrum of one single operator, measures the difference between the spectra of two different operators. This is done by…

Spectral Theory · Mathematics 2009-03-03 Helge Krueger , Gerald Teschl

This work is to consolidate current literature on Koopman-von Neumann (KvN) Mechanics into a simple and easy to understand text. KvN Mechanics is a branch of Classical Mechanics that has been recast into the mathematical language of Quantum…

Quantum Physics · Physics 2021-12-28 Daniel Piasecki

We discuss a relativistic theory of the atomic nuclei in the framework of the hamiltonian formalism and of the mesonic model of the nucleus. Attention is paid to the translational invariance of the theory. Our approach is centered on the…

Nuclear Theory · Physics 2008-11-26 R. Cenni , A. Molinari , G. Vagradov

The spectral curve is the key ingredient in the modern theory of classical integrable systems. We develop a construction of the ``quantum spectral curve'' and argue that it takes the analogous structural and unifying role on the quantum…

High Energy Physics - Theory · Physics 2007-05-23 A. Chervov , D. Talalaev

Parameter-dependent statistical properties of spectra of totally connected irregular quantum graphs with Neumann boundary conditions are studied. The autocorrelation functions of level velocities c(x) and c(w,x) as well as the distributions…

Chaotic Dynamics · Physics 2009-07-17 Oleh Hul , Petr Seba , Leszek Sirko

We study the properties of a quantum field with time as a dynamical variable. Temporal vibrations are introduced to restore the symmetry between time and space in a matter field. The system with vibrations of matter in time and space obeys…

General Physics · Physics 2021-11-03 Hou Y. Yau

We consider the variety of spectral measures that are induced by quasitraces on the spectrum of a self-adjoint operator in a simple separable unital and Z-stable C$^*$-algebra. This amounts to a continuous map from the simplex of…

Operator Algebras · Mathematics 2025-05-29 Andrew S. Toms , Hao Wan

The theory of Non-Relativistic Quantum Mechanics was created (or discovered) back in the 1920's mainly by Schr\"odinger and Heisenberg, but it is fair enough to say that a more modern and unified approach to the subject was introduced by…

Quantum Physics · Physics 2013-01-01 Augusto Cesar Lobo , Clyffe de Assis Ribeiro

In this study, we are concerned with spectral problems of second-order vector dynamic equations with two-point boundary value conditions and mixed derivatives, where the matrix-valued coefficient of the leading term may be singular, and the…

Classical Analysis and ODEs · Mathematics 2010-01-25 Douglas R. Anderson

The work is devoted to the study of the similarity of a correct restriction to some self-adjoint operator in the case when the minimal operator is symmetric. The resulting theorem was applied to the Sturm-Liouville operator and the Laplace…

Spectral Theory · Mathematics 2021-02-02 B. N. Biyarov , Z. A. Zakarieva , G. K. Abdrasheva

The spectral theory of graphs provides a bridge between classical signal processing and the nascent field of graph signal processing. In this paper, a spectral graph analogy to Heisenberg's celebrated uncertainty principle is developed.…

Information Theory · Computer Science 2013-08-02 Ameya Agaskar , Yue M. Lu