Description lagrangienne d'un boson scalaire à l'aide d'un triplet nucléaire
Differentiability of the transition semigroup of the stochastic Burgers equation, and application to the corresponding Hamilton-Jacobi equation
We consider a stochastic Burgers equation. We show that the gradient of the corresponding transition semigroup does exist for any bounded ; and can be estimated by a suitable exponential weight. An application to some Hamilton-Jacobi equation arising in Stochastic Control is given.
Differential dynamical systems in Lagrangian optimal control formulation. II. (Systemés dynamiques differéntielles á controle optimal formulation Lagrangienne. II.)
Differential equations with constraints in jet bundles: Lagrangian and Hamiltonian systems.
Diffusion times and stability exponents for nearly integrable analytic systems
For a positive integer n and R>0, we set . Given R>1 and n≥4 we construct a sequence of analytic perturbations (H j) of the completely integrable Hamiltonian on , with unstable orbits for which we can estimate the time of drift in the action space. These functions H j are analytic on a fixed complex neighborhood V of , and setting the time of drift of these orbits is smaller than (C(1/ɛ j)1/2(n-3)) for a fixed constant c>0. Our unstable orbits stay close to a doubly resonant surface,...
Dirac brackets in geometric dynamics
Discrete Euler-Poincaré and Euler Poincaré-Poisson equations for semidirect products and principal bundles.
Discrete-continuous systems with symmetry.
Distinguished Riemann-Hamilton geometry in the polymomentum electrodynamics
In this paper we develop the distinguished (d-) Riemannian differential geometry (in the sense of d-connections, d-torsions, d-curvatures and some geometrical Maxwell-like and Einstein-like equations) for the polymomentum Hamiltonian which governs the multi-time electrodynamics.
Doubly asymptotic trajectories of Lagrangian systems and a problem by Kirchhoff
We consider Lagrangian systems with Lagrange functions which exhibit a quadratic time dependence. We prove the existence of infinitely many solutions tending, as , to an «equilibrium at infinity». This result is applied to the Kirchhoff problem of a heavy rigid body moving through a boundless incompressible ideal fluid, which is at rest at infinity and has zero vorticity.
Drift and diffusion in phase space
Dual-null dynamics
Dynamical systems and Lagrangian spaces.