Results 51 to 60 of about 871,744 (361)
An Algorithm for Finding the Periodic Potential of the Three-dimensional Schrodinger Operator from the Spectral Invariants [PDF]
, 2010 In this paper, we investigate the three-dimensional Schrodinger operator with a periodic, relative to a lattice {\Omega} of R3, potential q. A special class V of the periodic potentials is constructed, which is easily and constructively determined from ...
Veliev, O. A.
core +2 more sources
AIMS Mathematics, 2022 In this study, we seek to establish new upper bounds for the mean curvature and constant sectional curvature of the first positive eigenvalue of the α-Laplacian operator on Riemannian manifolds.
Meraj Ali Khan +2 more
doaj +1 more source
On the location of LQ-optimal closed-loop poles [PDF]
Modeling, Identification and Control, 1992 Inequalities which bound the closed-loop eigenvalues in an LQ-optimal system are presented. It is shown that the eigenvalues are bounded by two half circles with radii r1 and r2 and centre at -alpha less than or equal to 0, where alpha=0 is the imaginary
David Di Ruscio
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Krein signature for instability of $\mathcal{PT}$-symmetric states
, 2017 Krein quantity is introduced for isolated neutrally stable eigenvalues associated with the stationary states in the $\mathcal{PT}$-symmetric nonlinear Schr\"{o}dinger equation.
Chernyavsky, Alexander +1 more
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A new spectral theory for nonlinear operators and its applications
Abstract and Applied Analysis, 1997 In this paper, by applying (p,k)-epi mapping theory, we introduce a new definition of spectrum for nonlinear operators which contains all eigenvalues, as in the linear case.
W. Feng
doaj +1 more source
Shape-dependence of transmission, reflection and absorption eigenvalue densities in disordered waveguides with dissipation [PDF]
, 2015 The universal bimodal distribution of transmission eigenvalues in lossless diffusive systems un- derpins such celebrated phenomena as universal conductance fluctuations, quantum shot noise in condensed matter physics and enhanced transmission in optics ...
Cao, H. +3 more
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Eigenvalues and the diameter of graphs [PDF]
Linear and Multilinear Algebra, 1995 Using eigenvalue interlacing and Chebyshev polynomials we find upper bounds for the diameter of regular and bipartite biregular graphs in terms of their eigenvalues. This improves results of Chung and Delorme and Sole. The same method gives upper bounds for the number of vertices at a given minimum distance from a given vertex set.
van Dam, E.R., Haemers, W.H.
openaire +8 more sources
Fast and accurate con-eigenvalue algorithm for optimal rational approximations [PDF]
, 2012 The need to compute small con-eigenvalues and the associated con-eigenvectors of positive-definite Cauchy matrices naturally arises when constructing rational approximations with a (near) optimally small $L^{\infty}$ error. Specifically, given a rational
Beylkin, G., Haut, T. S.
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Optimal Shrinkage of Eigenvalues in the Spiked Covariance Model. [PDF]
Annals of Statistics, 2013 We show that in a common high-dimensional covariance model, the choice of loss function has a profound effect on optimal estimation. In an asymptotic framework based on the Spiked Covariance model and use of orthogonally invariant estimators, we show ...
D. Donoho, M. Gavish, I. Johnstone
semanticscholar +1 more source
Pucci eigenvalues on geodesic balls
, 2016 We study the eigenvalue problem for the Riemannian Pucci operator on geodesic balls. We establish upper and lower bounds for the principal Pucci eigenvalues depending on the curvature, extending Cheng's eigenvalue comparison theorem for the Laplace ...
Ariturk, Sinan
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