David S. Tartakoff
Published 2006-09-28Version 1
We present an elementary, $L^2,$ proof of Fedi\u{\i}'s theorem on arbitrary (e.g., infinite order) degeneracy and extensions. In particular, the proof allows and shows $C^\infty,$ Gevrey, and real analytic hypoellipticity, and allows the coefficents to depend on the remaining variable as well.
General rogue waves of infinite order: Exact properties, asymptotic behavior, and effective numerical computation
Quantizations and global hypoellipticity for pseudodifferential operators of infinite order in classes of ultradifferentiable functions
Pseudodifferential operators of infinite order in spaces of tempered ultradistributions
![QR code for arXiv:math/0609778 [math.AP]](http://oss.arxitics.com/images/favicon.svg)