A scenario for transferring high scores
A Schur-Horn-Kostant convexity theorem for the diffeomorphism group of the annulus.
A Short Proof of a Theorem of Ruelle.
A simple characterization of sets satisfying the central sets theorem.
A simple mathematical model for Batesian mimicry.
A simple nonlinear dynamic model for unemployment: Explaining the spanish case.
A Simple Proof of Borel's Density Theorem.
A simple proof of polar decomposition in pseudo-Euclidean geometry
We give a simple direct proof of the polar decomposition for separated linear maps in pseudo-Euclidean geometry.
A simple proof of the non-integrability of the first and the second Painlevé equations
The first and the second Painlevé equations are explicitly Hamiltonian with time dependent Hamilton function. By a natural extension of the phase space one gets corresponding autonomous Hamiltonian systems in ℂ⁴. We prove that the latter systems do not have any additional algebraic first integral. In the proof equations in variations with respect to a parameter are used.
A singular lagrangian model for N-body relativistic interactions
A singular perturbation method for saddle connections and subharmonics of certain nonlinear differential equations with fixed saddle points.
Saddle connections and subharmonics are investigated for a class of forced second order differential equations which have a fixed saddle point. In these equations, which have linear damping and a nonlinear restoring term, the amplitude of the forcing term depends on displacement in the system. Saddle connections are significant in nonlinear systems since their appearance signals a homoclinic bifurcation. The approach uses a singular perturbation method which has a fairly broad application to saddle...
A solution to the bidimensional global asymptotic stability conjecture
A spanning set for the space of super cusp forms.
A spatially extended model for residential segregation.
A special case of the Garnier system, -polarized abelian surfaces and their moduli
A spectral gap property for subgroups of finite covolume in Lie groups
Let G be a real Lie group and H a lattice or, more generally, a closed subgroup of finite covolume in G. We show that the unitary representation of G on L²(G/H) has a spectral gap, that is, the restriction of to the orthogonal complement of the constants in L²(G/H) does not have almost invariant vectors. This answers a question of G. Margulis. We give an application to the spectral geometry of locally symmetric Riemannian spaces of infinite volume.
A splitting theorem for the Kupka component of a foliation of . Addendum to a paper by O. Calvo-Andrade and N. Soares
Here we show that a Kupka component of a codimension 1 singular foliation of with not a square is a complete intersection. The result implies the existence of a meromorphic first integral of .
A splitting theorem for the Kupka component of a foliation of . Addendum to an addendum to a paper by Calvo-Andrade and Soares
Here we show that a Kupka component of a codimension 1 singular foliation of is a complete intersection. The result implies the existence of a meromorphic first integral of . The result was previously known if was assumed to be not a square.
A stability theorem for foliations with singularities [Book]
A stretched exponential bound on the rate of growth of the number of periodic points for prevalent diffeomorphisms. I.