Abstract
Let H be a separable Hilbert space, and let φ and θ be two strongly commuting CP0-semigroups on B(H). In a previous paper we constructed a Hilbert space K ⊇ H and two (strongly) commuting E 0-semigroups α and β such that φs ̂ θt (PH APH) =PH αŝ βt(A)PH for all s, t < 0 and all A ∈ B(K). In this note we prove that if φ is not an automorphism semigroup, then the semigroup α (given by the above mentioned construction) is cocycle conjugate to the minimal *-endomorphic dilation of φ, and that if φ is an automorphism semigroup, then α is also an automorphism semigroup. In particular, we conclude that if φ is not an automorphism semigroup and has a bounded generator (in particular, if H is finite dimensional), then α is a type I E0-semigroup.
Original language | English |
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Pages (from-to) | 393-403 |
Number of pages | 11 |
Journal | Infinite Dimensional Analysis, Quantum Probability and Related Topics |
Volume | 11 |
Issue number | 3 |
DOIs | |
State | Published - 1 Sep 2008 |
Externally published | Yes |
Keywords
- CP-semigroup
- Cocycle conjugacy
- E-semigroup
- Minimal dilation
- Two-parameter semigroup
ASJC Scopus subject areas
- Statistical and Nonlinear Physics
- Statistics and Probability
- Mathematical Physics
- Applied Mathematics