7 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( Ï(\dot{x}) \bigr) = V'(|x|) \dfr…
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*} (Ï(x'))'=F(λ,t,x,x'). \end{equation*} Based on the topolog…
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…
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 cla…