an:01595432
Zbl 0979.35036
Bergamasco, Adalberto P.; Nunes, Wagner V. L.; Zani, S??rgio Lu??s
Global analytic hypoellipticity and pseudoperiodic functions
EN
Mat. Contemp. 18, 43-57 (2000).
00070215
2000
j
35H10 35N05 35F05
stationary phase
Summary: We show that a class of overdetermined systems on the 3-torus associated to a closed 1-form \(c\) on the 2-torus \(\mathbb{T}^2\simeq \mathbb{R}^2/2\pi\mathbb{Z}^2\) is globally analytic hypoelliptic if and only if every \(B:\mathbb{R}^2\to\mathbb{R}\) such that \(dB=\Im c\) is an open map at each point.