Arveson nests and operator factorization along commutative subspace lattices
John Daughtry, Ronald Johns · Proceedings of the American Mathematical Society · 1989
Similar commutative subspace lattices (CSL’s) are shown to be unitarily equivalent if certain sublattices (which may be taken to be nests!) are unitarily equivalent and a technical condition is satisfied. This result provides a connection between existing results for arbitrary similarities of countable CSL’s and similarities of general CSL’s by operators near the identity. One consequence is the generalizaton to CSL’s of a theorem of David Pitts on the relationship between similarity and unitary equivalence of nests he calls "injective."