Abstract
We give a classification of “small” monotone complete C *-algebras by order properties. We construct a corresponding semigroup. This classification filters out von Neumann algebras; they are mapped to the zero of the classifying semigroup. We show that there are 2c distinct equivalence classes (where c is the cardinality of the continuum). This remains true when the classification is restricted to special classes of monotone complete C *-algebras e.g. factors, injective factors, injective operator systems and commutative algebras which are subalgebras of ℓ∞. Some examples and applications are given.
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Saitô, K., Maitland Wright, J.D. On classifying monotone complete algebras of operators. Ricerche mat. 56, 321–355 (2007). https://doi.org/10.1007/s11587-007-0021-6
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DOI: https://doi.org/10.1007/s11587-007-0021-6