Bounded Ratios of Products of Principal Minors of Positive Definite Matrices
| dc.creator | Hall, H. Tracy | |
| dc.creator | Johnson, Charles R. | |
| dc.date | 2008-06-16 | |
| dc.date.accessioned | 2026-07-07T09:44:51Z | |
| dc.date.available | 2026-07-07T09:44:51Z | |
| dc.description | Considered is the multiplicative semigroup of ratios of products of principal minors bounded over all positive definite matrices. A long history of literature identifies various elements of this semigroup, all of which lie in a sub-semigroup generated by Hadamard-Fischer inequalities. Via cone-theoretic techniques and the patterns of nullity among positive semidefinite matrices, a semigroup containing all bounded ratios is given. This allows the complete determination of the semigroup of bounded ratios for 4-by-4 positive definite matrices, whose 46 generators include ratios not implied by Hadamard-Fischer and ratios not bounded by 1. For n > 4 it is shown that the containment of semigroups is strict, but a generalization of nullity patterns, of which one example is given, is conjectured to provide a finite determination of all bounded ratios. | |
| dc.description | 7 pages | |
| dc.identifier | https://arxiv.org/abs/0806.2645 | |
| dc.identifier | http://arxiv.org/abs/0806.2645 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/163018 | |
| dc.subject | Combinatorics | |
| dc.subject | Metric Geometry | |
| dc.subject | Rings and Algebras | |
| dc.subject | 15A45; 15A15, 15A48, 05B35 | |
| dc.title | Bounded Ratios of Products of Principal Minors of Positive Definite Matrices | |
| dc.type | text |