HOMOGENIZATION OF DEGENERATE WAVE-EQUATIONS WITH PERIODIC COEFFICIENTS

In this paper the authors discuss homogenization of hyperbolic equatio ns involving periodic coefficients which are degenerate relative to a certain direction. The general scheme by which effective equations are obtained is as the reiterated homogenization. The first step of the p rocess leads to equations describing the oscillatory behavior in the d irection of the propagation. Next, space averaging in the degenerate d irection gives the result. The process in the second step produces non local effects.