Numerical range and accretivity of operator products
نویسندگان
چکیده
منابع مشابه
On the Closure of the Numerical Range of an Operator
If T is a bounded linear mapping (briefly, operator) in a Hilbert space 3C, the numerical range of T is the set WiT) = {(Tx, x): |[x|| = l}; thus WiT) is convex [8, p. 131], and its closure clfW^r)] is compact and convex. Roughly speaking, in this note we observe that cl[TF(T)] can be uniquely defined for an element T of an abstract C*-algebra, while WiT) cannot. The C*-algebra setting yields a...
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ژورنال
عنوان ژورنال: Journal of Mathematical Analysis and Applications
سال: 1977
ISSN: 0022-247X
DOI: 10.1016/0022-247x(77)90008-7