Results 101 to 110 of about 1,194 (210)

Uniform resolvent estimates and absence of eigenvalues of biharmonic operators with complex potentials

, 2023
We quantify the subcriticality of the bilaplacian in dimensions greater than four by providing explicit repulsivity/smallness conditions on complex additive perturbations under which the spectrum remains stable.
Krejcirik, David, Cossetti, Lucrezia, Fanelli, Luca   +2 more
core  

Analytic continuation of resolvent kernels on noncompact symmetric spaces

, 2005
. Let X = G/K be a symmetric space of noncompact type and let ∆ be the Laplacian associated with a G-invariant metric on X. We show that the resolvent kernel of ∆ admits a holomorphic extension to a Riemann surface depending on the rank of the symmetric ...
Alexander Strohmaier
core  

Wavepackets driving trailing edge noise. Part II - Resolvent-based model

We present the results from a physics-based model of the trailing-edge (TE) noise radiated by an airfoil, obtained from resolvent analysis of the turbulent mean flow. In our approach, the acoustic model input is reduced to the optimal coherent structures
Demange, S.,, Yuan, Zhenyang,, Cavalieri, A.,, Hanifi, Ardeshir,, Oberleithner, K.,   +4 more
core   +1 more source

Asymptotics of the eigenvalues of approximating differential equations with d-different coefficients

Журнал Белорусского государственного университета: Математика, информатика, 2017
The overall objective is to describe the behavior of the eigenvalues of approximating operators and figuring out how to limit one turns oneʼs own importance.
Marina G. Kot
doaj  

Shared-Pole Carathéodory–Fejér Approximations for Linear Combinations of φ-Functions

Mathematics
We develop a shared denominator Carathéodory–Fejér (CF) method for efficiently evaluating linear combinations of φ-functions for matrices whose spectrum lies in the negative real axis, as required in exponential integrators for large stiff ODE systems ...
Awad H. Al-Mohy
doaj   +1 more source

The S-spectrum and the S-functional calculus

, 2018
\ua9 Springer Nature Switzerland AG 2018. The fundamental difficulty in developing a mathematically rigorous theory of quaternionic linear operators was the identification of suitable notions of quaternionic spectrum and quaternionic resolvent operator ...
Colombo F, Kimsey DP, Gantner J
core  

H-n-perturbations of self-adjoint operators and Krein's resolvent formula

, 2003
Supersingular H-n rank one perturbations of an arbitrary positive self-adjoint operator A acting in the Hilbert space H are investigated. The operator corresponding to the formal expression A(alpha) = A + alpha(phi,.)phi, alpha is an element of R, phi is
Kurasov, Pavel
core   +1 more source

Spectrum of the direct sum of operators

Electronic Journal of Differential Equations, 2012
We study the connection between spectral properties of direct the sum of operators in the direct sum of Hilbert spaces and its coordinate operators.
Elif Otkun Cevik, Zameddin I. Ismailov
doaj  

Robustly Linearized Model Predictive Control for Nonlinear Infinite-Dimensional Systems. [PDF]

IFAC Pap OnLine, 2023
El-Kebir H, Berlin R, Bentsman J, Ornik M.   +3 more
europepmc   +1 more source

Angle-resolved Auger spectrum of the N2 molecule

, 1996
Angle-resolved Auger electron spectra of N2 have been measured with good statistics at photon energies corresponding to the ?* resonance and the ?* shape resonance, below and above the N 1s threshold, respectively. Angular anisotropy is observed in both cases, but disappears as expected far above threshold.
Kivimäki, A., Neeb, M., Kempgens, B., Köppe, H., Bradshaw, A.   +4 more
openaire   +2 more sources