One More Proof of the Index Formula for Block Toeplitz Operators
نویسندگان
چکیده
This paper provides a new proof of the index formula for block Toeplitz operators. The idea is to calculate a certain integral formula for the winding number using Fourier series, expressing this in terms of Hankel operators, and producing the expected index.
منابع مشابه
The Index Formula of Douglas for Block Toeplitz Operators on the Bergman Space of the Ball
The index formula of Douglas is a formula which expresses the index of a Fredholm Toeplitz operator with a discontinuous symbol as the limit of the indices of a family of Fredholm Toeplitz operators with continuous symbols. This paper is concerned with Toeplitz operators on the Bergman space A of the unit ball of C. The symbols are supposed to be matrix functions with entries in C+H∞ or to be c...
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