Multiple solutions of the Dirichlet problem for harmonic maps from discs into 2-spheres.
A survey of recent progress on the multiplicity and stability problems for closed geodesics on Finsler 2-spheres is given.
We prove two explicit bounds for the multiplicities of Steklov eigenvalues on compact surfaces with boundary. One of the bounds depends only on the genus of a surface and the index of an eigenvalue, while the other depends as well on the number of boundary components. We also show that on any given Riemannian surface with smooth boundary the multiplicities of Steklov eigenvalues are uniformly bounded in .
We prove the existence of infinitely many geometrically distinct homoclinic orbits for a class of asymptotically periodic second order Hamiltonian systems.
We discuss the existence and multiplicity of positive solutions for a class of second order quasilinear equations. To obtain our results we will use the Ekeland variational principle and the Mountain Pass Theorem.
In this paper, we consider the problem of multiplicity of conformal metrics of prescribed scalar curvature on standard spheres . Under generic conditions we establish someMorse Inequalities at Infinity, which give a lower bound on the number of solutions to the above problem in terms of the total contribution of its critical points at Infinityto the difference of topology between the level sets of the associated Euler-Lagrange functional. As a by-product of our arguments we derive a new existence...
A multisymplectic 3-structure on an -dimensional manifold is given by a closed smooth 3-form of maximal rank on which is of the same algebraic type at each point of , i.e. they belong to the same orbit under the action of the group . This means that for each point the form is isomorphic to a chosen canonical 3-form on . R. Westwick [Linear Multilinear Algebra 10, 183–204 (1981; Zbl 0464.15001)] and D. Ž. Djoković [Linear Multilinear Algebra 13, 3–39 (1983; Zbl 0515.15011)] obtained...