Results 21 to 30 of about 275,056 (272)
Delayed stability switches in singularly perturbed predator-prey models [PDF]
, 2016 In this paper we provide an elementary proof of the existence of canard solutions for a class of singularly perturbed predator-prey planar systems in which there occurs a transcritical bifurcation of quasi steady states.
Banasiak, J., Tchamga, M. S. Seuneu
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On the dualization of Born–Infeld theories
Physics Letters B, 2015 We construct a general Lagrangian, quadratic in the field strengths of n abelian gauge fields, which interpolates between BI actions of n abelian vectors and actions, quadratic in the vector field-strengths, describing Maxwell fields coupled to non ...
Laura Andrianopoli +2 more
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Mass formulae for a class of nonrotating black holes [PDF]
, 1997 In the presence of a Killing symmetry, various self-gravitating field theories with massless scalars (moduli) and vector fields reduce to sigma-models, effectively coupled to 3-dimensional gravity.
Heusler, Markus
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Liu-type pretest and shrinkage estimation for the conditional autoregressive model.
PLoS ONE, 2023 Spatial regression models have recently received a lot of attention in a variety of fields to address the spatial autocorrelation effect. One important class of spatial models is the Conditional Autoregressive (CA). Theses models have been widely used to
Marwan Al-Momani
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Psi-series of quadratic vector fields on the plane [PDF]
Publicacions Matemàtiques, 1997 Psi-series (i.e., logarithmic series) for the solutions of quadratic vector fields on the plane are considered. Its existence and convergence is studied, and an algorithm for the location of logarithmic singularities is developed. Moreover, the relationship between psi-series and non-integrability is stressed and in particular it is proved that ...
Delshams Valdés, Amadeu, Mir, Arnau
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Higgsed Stueckelberg vector and Higgs quadratic divergence
Physics Letters B, 2015 Here we show that, a hidden vector field whose gauge invariance is ensured by a Stueckelberg scalar and whose mass is spontaneously generated by the Standard Model Higgs field contributes to quadratic divergences in the Higgs boson mass squared, and even
Durmuş Ali Demir +2 more
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Abelian integrals of quadratic hamiltonian vector fields with an invariant straight line [PDF]
, 1995 We prove that the lowest upper bound for the number of isolated zeros of the Abelian integrals associated to quadratic Hamiltonian vector fields having a center and an invariant straight line after quadratic perturbations is ...
Li, Chengzhi +2 more
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Form factors and decoupling of matter fields in four-dimensional gravity
Physics Letters B, 2019 We extend previous calculations of the non-local form factors of semiclassical gravity in 4D to include the Einstein–Hilbert term. The quantized fields are massive scalar, fermion and vector fields.
Sebastián A. Franchino-Viñas +3 more
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Quadratic Killing tensors on symmetric spaces which are not generated by Killing vector fields
Comptes Rendus. MathématiqueEvery Killing tensor field on the space of constant curvature and on the complex projective space can be decomposed into the sum of symmetric tensor products of Killing vector fields (equivalently, every polynomial in velocities integral of the geodesic ...
Matveev, Vladimir S., Nikolayevsky, Yuri
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3-dimensional piecewise linear and quadratic vector fields with invariant spheres
Electronic Journal of Qualitative Theory of Differential EquationsWe consider the class $\mathcal{X}$ of $3$-dimensional piecewise smooth vector fields that admit a first integral which leaves invariant any sphere centered at the origin.
Claudio Buzzi +2 more
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