Results 11 to 20 of about 160,382 (249)
Nonautonomous Dynamical Systems, 2022 In this work, we study the existence of periodic solutions for a class of linear partial functional differential equations with infinite delay. Inspiring by an existing study, by applying the perturbation theory of semi-Fredholm operators, we introduce a
Elazzouzi Abdelhai +2 more
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Nonlinear differential equations with perturbed Dirichlet integral boundary conditions
Boundary Value Problems, 2021 This paper is devoted to prove the existence of positive solutions of a second order differential equation with a nonhomogeneous Dirichlet conditions given by a parameter dependence integral.
Alberto Cabada, Javier Iglesias
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Open Mathematics, 2021 This work intends to treat the existence of mild solutions for the Hilfer fractional hybrid differential equation (HFHDE) with linear perturbation of first and second type in partially ordered Banach spaces. First, we establish the results concerning the
Gabeleh Moosa +3 more
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Cosmological Perturbation Theory Revisited [PDF]
, 2011 Increasingly accurate observations are driving theoretical cosmology toward the use of more sophisticated descriptions of matter and the study of nonlinear perturbations of FL cosmologies, whose governing equations are notoriously complicated.
Uggla, Claes, Wainwright, John
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Divergences in open quantum systems
Journal of High Energy Physics, 2018 We show that for cubic scalar field theories in five and more spacetime dimensions, and for the T = 0 limit of the Caldeira-Leggett model, the quantum master equation for long-wavelength modes initially unentangled from short-distance modes, and at ...
Cesar Agón, Albion Lawrence
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Comments on the quantum field theory of the Coulomb gas formalism
Journal of High Energy Physics, 2021 The holomorphic Coulomb gas formalism, as developed by Feigin-Fuchs, Dotsenko-Fateev and Felder, is a set of rules for computing minimal model observables using free field techniques. We attempt to derive and clarify these rules using standard techniques
Daniel Kapec, Raghu Mahajan
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The perturbation theory for linear operators of discrete type [PDF]
Pacific Journal of Mathematics, 1983 A perturbation result for unbounded operators of discrete type [\textit{N. Dunford} and \textit{J. Schwartz}, Linear Operators, part III (1971; Zbl 0243.47001): Spectral Operators, XIX, 2, Theorem 7] is derived using the notion of unconditional basis instead of assuming weak completeness of the underlying Banach space.
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SciPost Physics, 2022 We present exact expressions for certain integrated correlators of four superconformal primary operators in the stress tensor multiplet of $\cN=4$ supersymmetric Yang--Mills (SYM) theory with classical gauge group, $G_N$ $= SO(2N)$, $SO(2N+1)$, $USp(2N)$.
Daniele Dorigoni, Michael B. Green, Congkao Wen
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Journal of High Energy Physics, 2023 We consider a family of non-linear theories of electromagnetism that interpolate between Born-Infeld at small distances and the recently introduced ModMax at large distances.
Jose Beltrán Jiménez +2 more
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Comment on "Superinstantons and the Reliability of Perturbation Theory in Non-Abelian Models" [PDF]
, 1995 In a recent letter (hep-lat/9311019) A. Patrascioiu and E. Seiler argued that when taking into account "superinstantons configurations" the perturbative expansion and the beta-function of the two-dimensional non-linear sigma-model are modified at two ...
A. Patrascioiu +5 more
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