Compact Hankel Operators on the Hardy Space of the Polydisk
نویسندگان
چکیده
We show that a big Hankel operator on the standard Hardy space of the polydisk D, n > 1, cannot be compact unless it is the zero operator. We also show that this result can be generalized to certain Hankel operators defined on Hardy-Sobolev spaces of the polydisk.
منابع مشابه
Approximation numbers of composition operators on the Hardy space of the ball and of the polydisk
We give general estimates for the approximation numbers of composition operators on the Hardy space on the ball Bd and the polydisk D . Mathematics Subject Classification 2010. Primary: 47B33 – Secondary: 32A07 – 32A35 – 32A70 – 46E22 – 47B07 Key-words. approximation numbers; bounded symmetric domain; composition operator; Hardy space; polydisk; Reinhardt domain; several complex variables
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