Existence and non-existence of null-solutions for some non-Fuchsian partial differential operators with T-dependent coefficients

Abstract

Since M.S. Baouendi and C. Goulaouic ([2], [3]) defined partial differential operators of Fuchs type and proved theorems of Cauchy-Kowalevskaya type and Holmgren type, many authors have investigated operators of Fuchs type in various categories, that is, real-analytic, C∞ and so on. (Cf. [1], [4], [6], [8], [9], [11], [12], [17], [18], [19], [20], [21] etc.)