On joint essential spectra of doubly commuting n-tuples of p-hyponormal operators
نویسندگان
چکیده
منابع مشابه
A PUTNAM AREA INEQUALITY FOR THE SPECTRUM OF n-TUPLES OF p-HYPONORMAL OPERATORS
We prove an n-tuple analogue of the Putnam area inequality for the spectrum of a single p-hyponormal operator. Let B H denote the algebra of operators (i.e. bounded linear transformations) on a separable Hilbert space H. The operator A 2 B H is said to be p-hyponormal, 0 < p 1, if jA j2p jAj2p. Let H p denote the class of p-hyponormal operators. Then H 1 consists of the class of p-hyponorma...
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ژورنال
عنوان ژورنال: Glasgow Mathematical Journal
سال: 1998
ISSN: 0017-0895,1469-509X
DOI: 10.1017/s0017089500032705