A Beurling-Helson type theorem for modulation spaces
نویسندگان
چکیده
منابع مشابه
A Beurling-helson Type Theorem for Modulation Spaces
We prove a Beurling-Helson type theorem on modulation spaces. More precisely, we show that the only C changes of variables that leave invariant the modulation spaces M(R) are affine functions on R. A special case of our result involving the Sjöstrand algebra was considered earlier by A. Boulkhemair.
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ژورنال
عنوان ژورنال: Journal of Function Spaces and Applications
سال: 2009
ISSN: 0972-6802
DOI: 10.1155/2009/956891