Results 31 to 40 of about 1,034,900 (267)
Nash--Moser iteration and singular perturbations [PDF]
, 2011 We present a simple and easy-to-use Nash--Moser iteration theorem tailored for singular perturbation problems admitting a formal asymptotic expansion or other family of approximate solutions depending on a parameter $\eps\to 0.$ The novel feature is to ...
Texier, Benjamin, Zumbrun, Kevin
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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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Singular Perturbation on a Subdomain
Journal of Mathematical Analysis and Applications, 1997 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
G Aguilar, F Lisbona
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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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Supersymmetry and singular perturbations
Journal of Functional Analysis, 1985 Supersymmetric quantum theory (SSQT) is considered in view of perturbation theory. It is first shown in an abstract framework that SSQT may give rise to very singular perturbations, which make perturbation theories for eigenvalues (typically ground state energies) of the Hamiltonians or possibly for other quantities invalid.
Asao Arai, Asao Arai
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On Singular Perturbations of Quantum Dynamical Semigroups [PDF]
, 2017 We consider two examples of quantum dynamical semigroups obtained by singular perturbations of a standard generator which are special case of unbounded completely positive perturbations studied in detail in [11]. In Sec. 2, we propose a generalization of
A. Holevo
semanticscholar +1 more source
AIMS Mathematics, 2023 In this paper, the finite-time stability (FTS) of singular switched systems that have time-varying delays and perturbations is investigated. First, the concept of the FTS of time-varying delay singular switched systems is given, and a specific event ...
Yidan Wang, Li Xiao , Yanfeng Guo
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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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Non-Singular Bouncing Cosmology: Consistency of the Effective Description [PDF]
, 2015 We explicitly confirm that spatially flat non-singular bouncing cosmologies make sense as effective theories. The presence of a non-singular bounce in a spatially flat universe implies a temporary violation of the null energy condition, which can be ...
Koehn, Michael +2 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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