Vector Semi-Fredholm Toeplitz Operators and Mean Winding Numbers
نویسندگان
چکیده
منابع مشابه
Vector Semi-fredholm Toeplitz Operators and Mean Winding Numbers
For a continuous complex-valued function g on the real line without zeros, several notions of a mean winding number are introduced. We give necessary conditions for a Toeplitz operator with matrix-valued symbol G to be semi-Fredholm in terms of mean winding numbers of detG. The matrix function G is assumed to be continuous on the real line, and no other apriori assumptions on it are made.
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For a continuous nonvanishing complex-valued function g on the real line, several notions of a mean winding number are introduced. We give necessary conditions for a Toeplitz operator with matrixvalued symbol G to be semi-Fredholm in terms of mean winding numbers of detG. The matrix function G is assumed to be continuous on the real line, and no other apriori assumptions on it are made. AMS Sub...
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ژورنال
عنوان ژورنال: Nagoya Mathematical Journal
سال: 2009
ISSN: 0027-7630,2152-6842
DOI: 10.1017/s0027763000009703