| dc.creator | Corach, Gustavo | |
| dc.creator | Stojanoff, Demetrio | |
| dc.date | 2001 | |
| dc.date | 2019-11-04T13:30:12Z | |
| dc.identifier | http://sedici.unlp.edu.ar/handle/10915/84728 | |
| dc.identifier | issn:0024-3795 | |
| dc.description | For each n×n positive semidefinite matrix A we define the minimal index I(A)=max{λ≥0:A∘B≥λB for all B≥0} and, for each norm N, the N-index I<SUB>N</SUB>(A)=min{N(A∘B):B≥0 and N(B)=1}, where A ∘ B=[a<SUB>ij</SUB>b<SUB>ij</SUB>] is the Hadamard or Schur product of A=[a<SUB>ij</SUB>] and B=[b<SUB>ij</SUB>] and B≥0 means that B is a positive semidefinite matrix. A comparison between these indexes is done, for different choices of the norm N. As an application we find, for each bounded invertible selfadjoint operator S on a Hilbert space, the best constant M(S) such that ∥STS+S<SUP>-1</SUP>TS<SUP>-1</SUP>∥≥M(S)∥T∥ for all T≥0. | |
| dc.description | Facultad de Ciencias Exactas | |
| dc.format | application/pdf | |
| dc.format | 503-517 | |
| dc.language | en | |
| dc.rights | http://creativecommons.org/licenses/by-nc-sa/4.0/ | |
| dc.rights | Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) | |
| dc.subject | Ciencias Exactas | |
| dc.subject | Matemática | |
| dc.subject | 47A30 | |
| dc.subject | 47B15 | |
| dc.subject | Hadamard product | |
| dc.subject | Norm inequalities | |
| dc.subject | Positive semidefinite matrices | |
| dc.title | Index of Hadamard multiplication by positive matrices II | |
| dc.type | Articulo | |
| dc.type | Articulo | |
