The Cauchy problem for nonlinear hyperbolic equations with Levi condition
A quasilinear Cauchy problem of order \(m\) is considered for a weakly hyperbolic equation. It is assumed that the characteristic roots have constant multiplicity, higher than or equal to two. Since it is well known that such a type of equation requires conditions on the lower order terms, it is also assumed that for a generic value of the unknown function the Levi conditions are satisfied. A well posedness result is then proved.
scientific article; zbMATH DE number 1385246