Periodic solutions of a weakly nonlinear hyperbolic equation in and
Pour tout réel positif , on étudie la propagation de la régularité locale pour des solutions d’équations aux dérivées partielles hyperboliques non linéaires, admettant a priori la régularité minimale permettant de définir les expressions non linéaires figurant dans l’équation. En particulier, on démontre le théorème de propagation dans le cas des solutions essentiellement bornées (resp. lipschitziennes) de systèmes du premier ordre semi-linéaires (resp. quasi-linéaires).
The propagation of weak discontinuities for quasilinear systems with coefficients functionally dependent on the solution is studied. We demonstrate that, similarly to the case of usual quasilinear systems, the transport equation for the intensity of weak discontinuity is quadratic in this intensity. However, the contribution from the (nonlocal) functional dependence appears to be in principle linear in the jump intensity (with some exceptions). For illustration, several examples, including two hyperbolic...