English

E_0-semigroups and q-purity

Operator Algebras 2011-06-14 v1 Functional Analysis

Abstract

An E_0-semigroup is called q-pure if it is a CP-flow and its set of flow subordinates is totally ordered by subordination. The range rank of a positive boundary weight map is the dimension of the range of its dual map. Let K be a separable Hilbert space. We describe all q-pure E_0-semigroups of type II_0 which arise from boundary weight maps with range rank one over K. We also prove that no q-pure E_0-semigroups of type II_0 arise from boundary weight maps with range rank two over K. In the case when K is finite-dimensional, we provide a criterion to determine if two boundary weight maps of range rank one over K give rise to cocycle conjugate q-pure E_0-semigroups.

Keywords

Cite

@article{arxiv.1106.2304,
  title  = {E_0-semigroups and q-purity},
  author = {Christopher Jankowski and Daniel Markiewicz and Robert T. Powers},
  journal= {arXiv preprint arXiv:1106.2304},
  year   = {2011}
}

Comments

39 pages

R2 v1 2026-06-21T18:21:05.601Z