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Trench's Perturbation Theorem for Dynamic Equations [PDF]
Discrete Dynamics in Nature and Society, 2007 We consider a nonoscillatory second-order linear dynamic equation on a time scale together with a linear perturbation of this equation and give conditions on the perturbation that guarantee that the perturbed equation is also nonoscillatory and has ...
Martin Bohner, Stevo Stevic
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Gordon type theorem for measure perturbation
Electronic Journal of Differential Equations, 2011 Generalizing the concept of Gordon potentials to measures we prove a version of Gordon's theorem for measures as potentials and show absence of eigenvalues for these one-dimensional Schrodinger operators.
Christian Seifert
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Cosmological Perturbations and the Weinberg Theorem
Journal of Cosmology and Astroparticle Physics, 2015 The celebrated Weinberg theorem in cosmological perturbation theory states that there always exist two adiabatic scalar modes in which the comoving curvature perturbation is conserved on super-horizon scales.
Akhshik, Mohammad +2 more
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Feynman–Hellmann theorem for resonances and the quest for QCD exotica [PDF]
European Physical Journal C: Particles and Fields, 2017 The generalization of the Feynman–Hellmann theorem for resonance states in quantum field theory is derived. On the basis of this theorem, a criterion is proposed to study the possible exotic nature of certain hadronic states emerging in QCD.
J. Ruiz de Elvira +3 more
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A new class of fractional impulsive differential hemivariational inequalities with an application
Nonlinear Analysis, 2022 We consider a new fractional impulsive differential hemivariational inequality, which captures the required characteristics of both the hemivariational inequality and the fractional impulsive differential equation within the same framework.
Yun-hua Weng +3 more
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Analytic Resolving Families for Equations with Distributed Riemann–Liouville Derivatives
Mathematics, 2022 Some new necessary and sufficient conditions for the existence of analytic resolving families of operators to the linear equation with a distributed Riemann–Liouville derivative in a Banach space are established.
Vladimir E. Fedorov +3 more
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Analytic Resolving Families for Equations with the Dzhrbashyan–Nersesyan Fractional Derivative
Fractal and Fractional, 2022 In this paper, a criterion for generating an analytic family of operators, which resolves a linear equation solved with respect to the Dzhrbashyan–Nersesyan fractional derivative, via a linear closed operator is obtained.
Vladimir E. Fedorov +2 more
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Majorization, 4G Theorem and Schrödinger perturbations [PDF]
Journal of Evolution Equations, 2015 Schr dinger perturbations of transition densities by singular potentials may fail to be comparable with the original transition density. For instance this is so for the transition density of a subordinator perturbed by any time-independent unbounded potential.
Bogdan, Krzysztof +2 more
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A critical point theorem for a class of non-differentiable functionals with applications
AIMS Mathematics, 2020 This paper presents a multiplicity theorem for a kind of non-smooth functionals. The proof of this theorem relies on a suitable deformation lemma and the perturbation methods.
Yan Ning, Daowei Lu
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Best Fredholm perturbation theorems [PDF]
Studia Mathematica, 1988 Consider a basic Fredholm perturbation theorem; for example: Let T be a Fredholm operator and suppose that B is a linear operator with \(\| B\|
Schechter, M, Whitley, Robert
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