The Growth of Hypoelliptic Polynomials and Gevrey Classes
The Growth of Hypoelliptic Polynomials and Gevrey Classes
For given hypoelliptic polynomials P and Q, classes r^(O) and rg(fl) involving Gevrey type estimates on the successive iterates of the corresponding differential operators are defined.The equivalence of the inequality |ß(f)[2^C(l+|P(f)|2)\ fGR", and the inclusion r£(íí)<=rg4(Q) is proved.A differential polynomial P(D) on Rn of order m is elliptic if and …