IST IST

Seminar on
Functional Analysis and Applications

Supported by The Centre for Mathematics and its Applications - CEMAT and PRAXIS XXI.




  • December 6, 2002 , Friday - 15h00 (Room 3.10):


A Class of Singular Integral Operators with Flip and Unbounded Coefficients on Rearrangement-Invariant Spaces


Alexei Karlovich 


(Instituto Superior Técnico, U.T.L.)

Abstract. We prove Fredholm criteria for singular integral operators of the form P+aQ+bUQ, where P and Q are the Riesz projections, U is the flip operator, on a reflexive rearrangement-invariant space with nontrivial Boyd indices over the unit circle. We assume a priori that a is bounded, but b may be unbounded. The function b belongs to a class of, in general, unbounded functions that relates to the Douglas algebra H-infinity+C. This result is new even for Lebesgue spaces. It refines and generalizes some results of Kravchenko, Lebre, Litvinchuk, and Teixeira published in the Mathematische Nachrichten in 1995.




Seminars take place in Lisbon, I.S.T. - Post Graduation Building

Webpage: http://www.math.ist.utl.pt/funcional