Results 11 to 20 of about 8,505 (264)
Generating cosmological perturbations in non-singular Horndeski cosmologies
Journal of High Energy Physics, 2023 We construct a concrete model of Horndeski bounce with strong gravity in the past. Within this model we show that the correct spectra of cosmological perturbations may be generated at early contracting epoch, with mild fine-tuning ensuring that the ...
Yulia Ageeva +2 more
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On spectral stability for rank one singular perturbations [PDF]
Opuscula MathematicaWe study the embedded point spectrum of rank one singular perturbations of an arbitrary self-adjoint operator \(A\) on a Hilbert space \(\mathcal{H}\). These perturbations can be regarded as self-adjoint extensions of a densely defined closed symmetric ...
Mario Alberto Ruiz Caballero +1 more
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Asymptotics of Regular and Irregular Solutions in Chains of Coupled van der Pol Equations
Mathematics, 2023 Chains of coupled van der Pol equations are considered. The main assumption that motivates the use of special asymptotic methods is that the number of elements in the chain is sufficiently large.
Sergey Kashchenko
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Singular Perturbation on a Subdomain
Journal of Mathematical Analysis and Applications, 1997 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Aguilar, G, Lisbona, F
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Modelling of derivatives pricing using methods of spectral analysis
Journal of Vasyl Stefanyk Precarpathian National University, 2020 In this article expands the method of finding the approximate price for a wide class of derivative financial instruments. Using the spectral theory of self-adjoint operators in Hilbert space and the wave theory of singular and regular perturbations, the ...
Ivan Burtnyak, Anna Malytska
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Singular perturbations and singular arcs. I [PDF]
IEEE Transactions on Automatic Control, 1975 Singular perturbation theory is applied to obtain the asymptotic solution for the nearly singular optimal control of a constant linear system on a finite time interval In the limit as the control cost is reduced to zero, the initial control is found to have an impulse-like behavior, while the outer solution agrees asymptotically with the familiar ...
O'Malley, Robert E. jun. +1 more
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Karpatsʹkì Matematičnì Publìkacìï, 2018 The theoretical bases of this paper are the theory of spectral analysis and the theory of singular and regular perturbations. We obtain an approximate price of Ornstein-Uhlenbeck double barrier options with multidimensional stochastic diffusion as ...
I.V. Burtnyak, H.P. Malytska
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Singular Perturbations in Viscoelasticity
Rocky Mountain Journal of Mathematics, 1993 We study the singular perturbation for a class of partial integro- differential equations in viscoelasticity of the form \[ \rho u^ \rho_{tt} (t,x) = Eu^ \rho_{xx} (t,x) + \int ^ t _{-\infty} a (t-s) u^ \rho_{xx} (s,x) ds + \rho g (t,x) + f (x),\tag{a} \] when the density \(\rho\) of the material goes to zero. We will prove that when \(\rho \to 0\) the
Grimmer, Ronald, Liu, Hetao
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Asymptotics of the Solution of Bisingular Problem for a System of Linear Parabolic Equations. I
Моделирование и анализ информационных систем, 2013 Given a bisingular parabolic problem for a system of linear parabolic equations, we construct an asymptotics for the solution of any order with respect to a small parameter, without using the joining procedure for asymptotic expansions.
M. V. Butuzova
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Axiomatic Approach in the Analytic Theory of Singular Perturbations
Axioms, 2020 Introduced by S.A. Lomov, the concept of a pseudoanalytic (pseudoholomorphic) solution laid the foundation for the development of the singular perturbation analytical theory.
Margarita Besova, Vasiliy Kachalov
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