Regularity of class of differential operators

Abstract

In this paper we deal with the problem of regularity for non hypo-elliptic partial differential equations with polynomial coefficients. An operator $A$ on on the space of tempered distributions ${\mathcal{S}}^{\prime }$ is regular if $u$ belongs to the Schwartz class $\mathcal{S}$ whenever $Au\in \mathcal{S}$. By using tensor products of topological vector spaces and a kind of Wigner transform we reduce the study of regularity of a non hypo-elliptic differential operator, like the twisted laplacian, to a hypo-elliptic one, like the harmonic oscillator.

9 pages