Results 1 to 10 of about 2,171,485 (241)
Discrete spectra for some complex infinite band matrices [PDF]
Opuscula Mathematica, 2021 Under suitable assumptions the eigenvalues for an unbounded discrete operator \(A\) in \(l_2\), given by an infinite complex band-type matrix, are approximated by the eigenvalues of its orthogonal truncations. Let \[\Lambda (A)=\{\lambda \in {\rm Lim}_{
Maria Malejki
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Asymptotic expansion of large eigenvalues for a class of unbounded Jacobi matrices [PDF]
Opuscula Mathematica, 2020 We investigate a class of infinite tridiagonal matrices which define unbounded self-adjoint operators with discrete spectrum. Our purpose is to establish the asymptotic expansion of large eigenvalues and to compute two correction terms explicitly.
Ayoub Harrat +2 more
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IEEE Photonics Journal, 2023 Nonlinear frequency division multiplexing (NFDM) system is an optional candidate to overcome the fiber nonlinearity limit. A full-spectrum modulated NFDM system, modulating data on combined continuous spectrum (CS) and discrete spectrum (DS) together ...
Ruofan Zhang +7 more
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Современная математика: Фундаментальные направления, 2023 In this paper, we study a problem of normal oscillations of a homogeneous mixture of several viscous compressible fluids filling a bounded domain of three-dimensional space with an infinitely smooth boundary.
D. A. Zakora
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Discrete spectrum of zero order pseudodifferential operators [PDF]
Opuscula Mathematica, 2023 We study the rate of convergence of eigenvalues to the endpoints of essential spectrum for zero order pseudodifferential operators on a compact manifold.
Grigori Rozenblum
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Asymptotics of the discrete spectrum for complex Jacobi matrices [PDF]
Opuscula Mathematica, 2014 The spectral properties and the asymptotic behaviour of the discrete spectrum for a special class of infinite tridiagonal matrices are given. We derive the asymptotic formulae for eigenvalues of unbounded complex Jacobi matrices acting in \(l^2(\mathbb{N}
Maria Malejki
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Nonperturbative Quantization Approach for QED on the Hopf Bundle
Universe, 2021 We consider the Dirac equation and Maxwell’s electrodynamics in R×S3 spacetime, where a three-dimensional sphere is the Hopf bundle S3→S2. In both cases, discrete spectra of classical solutions are obtained.
Vladimir Dzhunushaliev +1 more
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Discrete Spectrum cover Signal Waveform Design and Generation Method
Leida xuebao, 2023 Radio Frequency-screen is one of the earliest radar active antijamming measures. It achieves antijamming by transmitting cover pulses of different frequencies before the radar pulse signal to induce enemy jammers.
Jianglan TANG +4 more
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Spectra of some selfadjoint Jacobi operators in the double root case [PDF]
Opuscula Mathematica, 2015 In this paper we prove a mixed spectrum of Jacobi operators defined by \(\lambda_n=s(n)(1+x(n))\) and \(q_n=-2s(n)(1+y(n))\), where \((s(n))\) is a real unbounded sequence, \((x(n))\) and \((y(n))\) are some perturbations.
Wojciech Motyka
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Low complexity subshifts have discrete spectrum
Forum of Mathematics, Sigma, 2023 We prove results about subshifts with linear (word) complexity, meaning that $\limsup \frac {p(n)}{n} < \infty $ , where for every n, $p(n)$ is the number of n-letter words appearing in sequences in the subshift.
Darren Creutz, Ronnie Pavlov
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