39 citations · 75 across the 32 of their papers we have counts for
38 papers
Periodic orbits with prescribed negative energy for relativistic Keplerian problems
Alberto Boscaggin, Guglielmo Feltrin, Duccio Papini
Using a variational approach, we study the existence of periodic solutions with prescribed energy for the relativistic equation \begin{equation*} \dfrac{\mathrm{d}}{\mathrm{d}t}\le…
Continuation theorems for periodic systems and applications to problems with nonlinear time-dependent differential operators
Pierluigi Benevieri, Guglielmo Feltrin
In this paper we propose some continuation theorems for the periodic problem \begin{equation*} \begin{cases} \, x_{i}' = g_{i}(t,x_{i+1}), &i=1,\ldots,n-1, \\ \, x_{n}' = h(t,x_{1}…
Bifurcation from periodic solutions of central force problems in the three-dimensional space
Alberto Boscaggin, Guglielmo Feltrin, Duccio Papini
The paper deals with electromagnetic perturbations of a central force problem of the form \begin{equation*} \dfrac{\mathrm{d}}{\mathrm{d}t} \bigl( φ(\dot{x}) \bigr) = V'(|x|) \dfra…
A proof of a conjecture on the multiplicity of positive solutions of an indefinite superlinear problem
Guglielmo Feltrin, Julián López-Gómez, Juan Carlos Sampedro
This paper solves in a positive manner a conjecture stated in 2000 by R. Gómez-Reñasco and J. López-Gómez regarding the multiplicity of positive solutions of a paradigmatic class o…
A Poincaré-Birkhoff theorem for multivalued successor maps with applications to periodic superlinear Hamiltonian systems
Guglielmo Feltrin, Alessandro Fonda, Andrea Sfecci
We provide a new version of the Poincaré-Birkhoff theorem for possibly multivalued successor maps associated with planar non-autonomous Hamiltonian systems. As an application, we p…
Atypical bifurcation for periodic solutions of -Laplacian systems
Pierluigi Benevieri, Guglielmo Feltrin
In this paper, we study the -periodic solutions of the parameter-dependent -Laplacian equation \begin{equation*} (ϕ(x'))'=F(λ,t,x,x'). \end{equation*} Based on the topologica…
Nearly-circular periodic solutions of perturbed relativistic Kepler problems: the fixed-period and the fixed-energy problems
Alberto Boscaggin, Guglielmo Feltrin, Duccio Papini
The paper studies the existence of periodic solutions of a perturbed relativistic Kepler problem of the type \begin{equation*} \dfrac{\mathrm{d}}{\mathrm{d}t}\left(\frac{m\dot{x}}{…
Uniqueness, non-degeneracy, and exact multiplicity of positive solutions for superlinear elliptic problems
Guglielmo Feltrin, Christophe Troestler
In this paper, we focus our attention on the positive solutions to second-order nonlinear ordinary differential equations of the form , where is a sign-changing…
Bifurcation of closed orbits of Hamiltonian systems with application to geodesics of the Schwarzschild metric
Alberto Boscaggin, Walter Dambrosio, Guglielmo Feltrin
We investigate bifurcation of closed orbits with a fixed energy level for a class of nearly integrable Hamiltonian systems with two degrees of freedom. More precisely, we make a jo…
Homoclinic and heteroclinic solutions for non-autonomous Minkowski-curvature equations
Guglielmo Feltrin, Maurizio Garrione
We deal with the non-autonomous parameter-dependent second-order differential equation \begin{equation*} δ\left( \dfrac{v'}{\sqrt{1-(v')^{2}}} \right)' + q(t) f(v)= 0, \quad t\in\m…
Prescribed energy periodic solutions of Kepler problems with relativistic corrections
Alberto Boscaggin, Walter Dambrosio, Guglielmo Feltrin
We consider two different relativistic versions of the Kepler problem in the plane: the first one involves the relativistic differential operator, the second one involves a correct…
Periodic solutions to superlinear indefinite planar systems: a topological degree approach
Guglielmo Feltrin, Juan Carlos Sampedro, Fabio Zanolin
We deal with a planar differential system of the form \begin{equation*} \begin{cases} \, u' = h(t,v), \\ \, v' = - λa(t) g(u), \end{cases} \end{equation*} where is -periodic…
Equilibrium points, periodic solutions and the Brouwer fixed point theorem for convex and non-convex domains
Guglielmo Feltrin, Fabio Zanolin
We show the direct applicability of the Brouwer fixed point theorem for the existence of equilibrium points and periodic solutions for differential systems on general domains satis…
Periodic perturbations of central force problems and an application to a restricted -body problem
Alberto Boscaggin, Walter Dambrosio, Guglielmo Feltrin
We consider a perturbation of a central force problem of the form \begin{equation*} \ddot x = V'(|x|) \frac{x}{|x|} + \varepsilon \,\nabla_x U(t,x), \quad x \in \mathbb{R}^{2} \set…
On the number of positive solutions to an indefinite parameter-dependent Neumann problem
Guglielmo Feltrin, Elisa Sovrano, Andrea Tellini
We study the second-order boundary value problem \begin{equation*} \begin{cases} \, -u''=a_{λ,μ}(t) \, u^{2}(1-u), & t\in(0,1), \\ \, u'(0)=0, \quad u'(1)=0, \end{cases} \end{equat…
Bound sets for a class of -Laplacian operators
Guglielmo Feltrin, Fabio Zanolin
We provide an extension of the Hartman-Knobloch theorem for periodic solutions of vector differential systems to a general class of -Laplacian differential operators. Our main t…
Uniqueness of positive solutions for boundary value problems associated with indefinite -Laplacian type equations
Alberto Boscaggin, Guglielmo Feltrin, Fabio Zanolin
The paper provides a uniqueness result for positive solutions of the Neumann and periodic boundary value problems associated with the -Laplacian equation \begin{equation*} \bigl…
Positive solutions for a Minkowski-curvature equation with indefinite weight and super-exponential nonlinearity
Alberto Boscaggin, Guglielmo Feltrin, Fabio Zanolin
We investigate the existence of positive solutions for a class of Minkowski-curvature equations with indefinite weight and nonlinear term having superlinear growth at zero and supe…
Periodic solutions to a perturbed relativistic Kepler problem
Alberto Boscaggin, Walter Dambrosio, Guglielmo Feltrin
We consider a perturbed relativistic Kepler problem \begin{equation*} \dfrac{\mathrm{d}}{\mathrm{d}t}\left(\dfrac{m\dot{x}}{\sqrt{1-|\dot{x}|^2/c^2}}\right)=-α\, \dfrac{x}{|x|^3}+\…
Pairs of positive radial solutions for a Minkowski-curvature Neumann problem with indefinite weight
Alberto Boscaggin, Guglielmo Feltrin
We prove the existence of a pair of positive radial solutions for the Neumann boundary value problem \begin{equation*} \begin{cases} \, \mathrm{div}\,\Biggl{(} \dfrac{\nabla u}{\sq…
Multiplicity of clines for systems of indefinite differential equations arising from a multilocus population genetics model
Guglielmo Feltrin, Paolo Gidoni
We investigate sufficient conditions for the presence of coexistence states for different genotypes in a diploid diallelic population with dominance distributed on a heterogeneous…
High multiplicity and chaos for an indefinite problem arising from genetic models
Alberto Boscaggin, Guglielmo Feltrin, Elisa Sovrano
We deal with the periodic boundary value problem associated with the parameter-dependent second-order nonlinear differential equation \begin{equation*} u'' + cu' + \bigr{(} λa^{+}(…
Parabolic orbits in Celestial Mechanics: a functional-analytic approach
Alberto Boscaggin, Walter Dambrosio, Guglielmo Feltrin +1
We prove the existence of half-entire parabolic solutions, asymptotic to a prescribed central configuration, for the equation \begin{equation*} \ddot{x} = \nabla U(x) + \nabla W(t,…
Positive periodic solutions to an indefinite Minkowski-curvature equation
Alberto Boscaggin, Guglielmo Feltrin
We investigate the existence, non-existence, multiplicity of positive periodic solutions, both harmonic (i.e., -periodic) and subharmonic (i.e., -periodic for some integer $…