Non-hyperbolic closed geodesics.
Nonlinear connections and semisprays on tangent manifolds.
Nonlinear dynamics systems - bifurcations, continuation methods, periodic solutions
Nonlinear eigenvalue problems
Nonlinear elliptic equations involving critical Sobolev exponent on compact Riemannian manifolds in presence of symmetries.
In this paper, we study a nonlinear elliptic equation with critical exponent, invariant under the action of a subgroup G of the isometry group of a compact Riemannian manifold. We obtain some existence results of positive solutions of this equation, and under some assumptions on G, we show that we can solve this equation for supercritical exponents.
Nonlinear elliptic equations on compact Riemannian manifolds and asymptotics of Emden equations.
Nonlinear elliptic systems with exponential nonlinearities.
Nonlinear oscillations of completely resonant wave equations
Nonlinear parabolic problems on manifolds, and a nonexistence result for the noncompact Yamabe problem.
Nonlinear Schrödinger equation on four-dimensional compact manifolds
We prove two new results about the Cauchy problem in the energy space for nonlinear Schrödinger equations on four-dimensional compact manifolds. The first one concerns global well-posedness for Hartree-type nonlinearities and includes approximations of cubic NLS on the sphere as a particular case. The second one provides, in the case of zonal data on the sphere, local well-posedness for quadratic nonlinearities as well as a necessary and sufficient condition of global well-posedness for small energy...
Nonlinear Small Data Scattering for the Wave and Klein-Gordon Equation.
Nonlinear structures determined by measures on Banach spaces
Nonlinear subelliptic Schrödinger equations with external magnetic field.
Nonlinear Variational Inequalities Depending on a Parameter
This paper develops the results announced in the Note [14]. Using an eigenvalue problem governed by a variational inequality, we try to unify the theory concerning the post-critical equilibrium state of a thin elastic plate subjected to unilateral conditions.
Nonlinear vibrations of completely resonant wave equations
We present recent existence results of small amplitude periodic and quasi-periodic solutions of completely resonant nonlinear wave equations. Both infinite-dimensional bifurcation phenomena and small divisors difficulties occur. The proofs rely on bifurcation theory, Nash-Moser implicit function theorems, dynamical systems techniques and variational methods.
Nonlocal symmetries and generation of solutions for partial differential equations.
Non-minimal Yang-Mills fields and dynamics.
Nonrational, nonsimple convex polytopes in symplectic geometry.
Nonsmoothable Zp actions on contractible 4-manifolds.
Non-split almost complex and non-split Riemannian supermanifolds
Non-split almost complex supermanifolds and non-split Riemannian supermanifolds are studied. The first obstacle for a splitting is parametrized by group orbits on an infinite dimensional vector space. For almost complex structures, the existence of a splitting is equivalent to the existence of local coordinates in which the almost complex structure can be represented by a purely numerical matrix, i.e. containing no Grassmann variables. For Riemannian metrics, terms up to degree 2 are allowed in...