34cxx37cxx37dxx37exx37nxx70kxx 37cxx37dxx37bxx34cxx34dxx applications chaoticbehaviorinsystems differentiabledynamicalsystems differentialequations differentialoperators dynamicalsystemsandergodictheory dynamicalsystemswithhyperbolicbehavior dynamics elliptic ellipticdifferentialequations ellipticfunctions exponentialfunctions low-dimensionaldynamicalsystems mechanicsofparticlesandsystems nonlinear nonlineardifferentialequations nonlineardynamics nonlineartheories ordinarydifferentialequations parabolic parabolicdifferentialequations smoothdynamicalsystems:generaltheory stabilitytheory topologicaldynamics