MULTITIME FLOQUET THEORY

ABSTRACT. This paper is a contribution to the Floquet ideas applied for multitime overde-termined linear first order PDE dynamical systems with multi-periodic coefficients. The main results include: (1) a formula for the fundamental matrix; (2) the equivalence between a T-multi-periodic PDE system and a constant coefficient PDE system; (3) a new criteria for the controllability of overdetermined linear PDE systems. 1