On orthogonal systems of matrix algebras
✍ Scribed by Mihály Weiner
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 223 KB
- Volume
- 433
- Category
- Article
- ISSN
- 0024-3795
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✦ Synopsis
In this work it is shown that certain interesting types of orthogonal system of subalgebras (whose existence cannot be ruled out by the trivial necessary conditions) cannot exist. In particular, it is proved that there is no orthogonal decomposition of
number of maximal abelian subalgebras and factors isomorphic to M n (C) in which the number of factors would be 1 or 3.
In addition, some new tools are introduced, too: for example, a quantity c(A, B), which measures "how close" the subalgebras A, B ⊂ M n (C) are to being orthogonal. It is shown that in the main cases of interest, c(A , B ) -where A and B are the commutants of A and B, respectively -can be determined by c(A, B) and the dimensions of A and B. The corresponding formula is used to find some further obstructions regarding orthogonal systems.
📜 SIMILAR VOLUMES
An algebraic theory of orthogonality for vector polynomials with respect to a matrix of linear forms is presented including recurrence relations, extension of the Shohat Favard theorem, of the Christoffel Darboux formula, and its converse. The connection with orthogonal matrix polynomials is describ
Let M n be the algebra of all n × n complex matrices and P n the set of all idempotents in M n . Suppose φ : M n → M n is a surjective map satisfying A -λB ∈ P n if and only if