Analytic hypoellipticity for sums of squares of vector fields
Tom 70 / 1998
Annales Polonici Mathematici 70 (1998), 117-129
DOI: 10.4064/ap-70-1-117-129
Streszczenie
We discuss the open problem of analytic hypoellipticity for sums of squares of vector fields, including some recent partial results and a conjecture of Treves.