Results 41 to 50 of about 518,086 (284)
Many bounded versions of undecidable problems are NP-hard
SciPost Physics, 2023 Several physically inspired problems have been proven undecidable; examples are the spectral gap problem and the membership problem for quantum correlations.
Andreas Klingler, Mirte van der Eyden, Sebastian Stengele, Tobias Reinhart, Gemma de las Cuevas
doaj +1 more source
Pade approximation of the S-matrix as a way of locating quantum resonances and bound states
, 2011 It is shown that the spectral points (bound states and resonances) generated by a central potential of a single-channel problem, can be found using rational parametrization of the S-matrix. To achieve this, one only needs values of the S-matrix along the
Baker G A +9 more
core +1 more source
Phase Field Failure Modeling: Brittle‐Ductile Dual‐Phase Microstructures under Compressive Loading
Advanced Engineering Materials, EarlyView.The approach by Amor and the approach by Miehe and Zhang for asymmetric damage behavior in the phase field method for fracture are compared regarding their fitness for microcrack‐based failure modeling. The comparison is performed for the case of a dual‐phase microstructure with a brittle and a ductile constituent.
Jakob Huber, Jan Torgersen, Ewald Werner
wiley +1 more source
Advanced Functional Materials, EarlyView.This study presents novel anti‐counterfeiting tags with multilevel security features that utilize additional disguise features. They combine luminescent nanosized Ln‐MOFs with conductive polymers to multifunctional mixed‐matrix membranes and powder composites. The materials exhibit visible/NIR emission and matrix‐based conductivity even as black bodies.
Moritz Maxeiner +9 more
wiley +1 more source
Advanced Nonlinear StudiesResorting to the spectral analysis of the 4 × 4 matrix spectral problem, we construct a 4 × 4 matrix Riemann–Hilbert problem to solve the initial value problem for the Hermitian symmetric space derivative nonlinear Schrödinger equation.
Chen Mingming, Geng Xianguo, Liu Huan
doaj +1 more source
On the Distance Spectral Radius of Trees with Given Degree Sequence
Discussiones Mathematicae Graph Theory, 2020 We consider the problem of maximizing the distance spectral radius and a slight generalization thereof among all trees with some prescribed degree sequence.
Dadedzi Kenneth +2 more
doaj +1 more source
Inverse Spectral Problem for Differential Operators with Rational Scattering Matrix Functions
Journal of Differential Equations, 1995 The authors obtain explicit formulas for the potential of an ordinary differential operator if its spectral function or its scattering functions are rational matrix functions which are analytic and invertible on the real line including infinity. The solution is given in terms of a realization of the spectral function or of the scattering function.
Alpay, D., Gohberg, I.
openaire +2 more sources
Second order accurate distributed eigenvector computation for extremely large matrices
, 2009 We propose a second-order accurate method to estimate the eigenvectors of extremely large matrices thereby addressing a problem of relevance to statisticians working in the analysis of very large datasets.
d'Aspremont, Alexandre +1 more
core +2 more sources
Advanced Functional Materials, EarlyView.Shellac, a centuries‐old natural resin, is reimagined as a green material for flexible electronics. When combined with silver nanowires, shellac films deliver transparency, conductivity, and stability against humidity. These results position shellac as a sustainable alternative to synthetic polymers for transparent conductors in next‐generation ...
Rahaf Nafez Hussein +4 more
wiley +1 more source
MathematicsThe aim of this paper is to analyze a specific fourth-order matrix spectral problem involving four potentials and two free nonzero parameters and construct an associated integrable hierarchy of bi-Hamiltonian equations within the zero curvature ...
Wen-Xiu Ma
doaj +1 more source