Treffer: A remark on boundary estimates on unbounded Z ( q ) domains in.

The goal of this note is to explore the relationship between the Folland–Kohn basic estimate and theZ(q)-condition. In particular, on unbounded domains, we prove that the Folland–Kohn basic estimate is equivalent to a uniformZ(q) condition. As a corollary, we observe that despite the Siegel upper half space being strictly pseudoconvex and biholomorphic to the unit ball, it fails to satisfy uniform strict pseudoconvexity and hence the Folland–Kohn basic estimate fails. [ABSTRACT FROM AUTHOR]