Slipped non-Positive Reduced Dynamics and Entanglement

Abstract

Non-positive Markov approximations are sometimes used to describe the dynamics of qubits in weak interaction with suitable environments; the appearance of negative probabilities is avoided by assuming that the transient regime eliminates from the possible initial conditions those qubit states which would otherwise be mapped out of the Bloch sphere by the subsequent Markovian time-evolution. By means of a simple model, we discuss some physical inconsistencies of this approach in relation to entanglement; in particular, we show that slipped non-positive reduced dynamics might create entanglement through a purely local action.

23 pages, 7 figures, LaTex

References in corpus (5)

• Entanglement of Formation of an Arbitrary State of Two Qubits
• Mixed State Entanglement and Quantum Error Correction
• Open Quantum Dynamics: Complete Positivity and Entanglement
• Mixed-state entanglement and quantum communication
• About non-positive evolutions in open system dynamics

Cited by in corpus (6)

• Refined Weak Coupling Limit: Coherence, Entanglement and Non-Markovianity
• Quantum Thermodynamics in the Refined Weak Coupling Limit
• Redfield reduced dynamics and entanglement
• Local generation of entanglement with Redfield dynamics
• Fermionic duality: General symmetry of open systems with strong dissipation and memory
• Non-Positive Semigroup Dynamics in Continuous Variable Models