By Caixing Gu and Jonathan E. Shapiro
This paper appears in Mathematische Annalen, Volume 319 Issue 3 (2001)
You can see it on their web site here.
We give a formula for
and describe when .
We explore the hyponormality of Toeplitz operators whose symbols are of
circulant type and some more general types. In addition, we discuss
formulas for and estimates of the rank of the self-commutator of a hyponormal
Back to Jonathan Shapiro's home page.