The Extreme Points of Order Intervals of Positive Operators
β Scribed by W.L. Green; T.D. Morley
- Publisher
- Elsevier Science
- Year
- 1994
- Tongue
- English
- Weight
- 433 KB
- Volume
- 15
- Category
- Article
- ISSN
- 0196-8858
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β¦ Synopsis
Consider the order interval of operators ([0, A}={X \mid 0 \leq X \leq A}). In finite dimensions (or if (A) is invertible) then the extreme points of ([0, A]) are the shorted operators (generalized Schur complements) of (A). This is false in the general infinite dimensional case. We give an example arising from the discretization of the biharmonic equation. We also give necessary and sufficient conditions for an extreme point (X_{0}) to be a short of (A, 1994) Academic Press, Inc.
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