Abstract
The norm of a matrix B as a Hadamard multiplier is the norm of the map X → X • B where • is the Hadamard or entrywise product of matrices. We give a geometric interpretation to a criterion of Haagerup and use this interpretation to find an explicit formula for the Hadamard multiplier norms of real 2 × 2 matrices. For Hermitian matrices with one positive eigenvalue, we give necessary and sufficient conditions for the norm to be the magnitude of the largest entry.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.