Global Gevrey hypoellipticity on the torus for a class of systems of complex vector fields

Alexandre Arias Junior, Alexandre Kirilov, Cleber de Medeira

Let $L_j={\partial }_{t_j}+(a_j+i{b}_j)(t_j){\partial }_x,j=1,\dots ,n,$ be a system of vector fields defined on the torus ${\mathbb{T}}_t^n\times {\mathbb{T}}_x^1$, where the coe…