Principal functions and invariant subspaces of hyponormal operators
نویسندگان
چکیده
منابع مشابه
Hyponormal matrices and semidefinite invariant subspaces in indefinite inner products
It is shown that, for any given polynomially normal matrix with respect to an indefinite inner product, a nonnegative (with respect to the indefinite inner product) invariant subspace always admits an extension to an invariant maximal nonnegative subspace. Such an extension property is known to hold true for general normal matrices if the nonnegative invariant subspace is actually neutral. An e...
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ژورنال
عنوان ژورنال: Hokkaido Mathematical Journal
سال: 1983
ISSN: 0385-4035
DOI: 10.14492/hokmj/1381757787