exceptional space

exceptional space

[ek′sep·shən·əl ′spās] (quantum mechanics) A space used to describe a system with a finite number of degrees of freedom in a generalization of quantum mechanics; this generalization is achieved by reformulating quantum mechanics in terms of a Jordan algebra of observables and states, and then generalizing this to the exceptional Jordan algebra realized by the algebra of 3 × 3 Hermitian matrices over the Cayley numbers.