Numerical radius inequalities for products and sums of semi-Hilbertian space operators
نویسندگان
چکیده
New inequalities for the A-numerical radius of products and sums operators acting on a semi-Hilbert space, i.e. space generated by positive semidefinite operator A, are established. In particular, every T S which admit A-adjoints, it is proved that ?A(TS) ? 1/2?A(ST) + 1/4 (||T||A||S||A ||TS||A), where ?A(T) ||T||A denote A-operator seminorm an respectively.
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ژورنال
عنوان ژورنال: Filomat
سال: 2022
ISSN: ['2406-0933', '0354-5180']
DOI: https://doi.org/10.2298/fil2204415b