Colored noise driven unitarity violation causing dynamical quantum state reduction

TL;DR

This paper formalizes models of quantum state reduction driven by colored noise through unitarity violations, showing their connection to known master equations and adherence to Born's rule.

Contribution

It introduces a formalism for unitarity violations causing dynamical quantum state reduction with explicit norm-preservation and links to GKSL equations.

Findings

Models reduce to GKSL equations in a specific limit

Born's rule emerges naturally in the model

Formalism allows exploration of colored noise effects on quantum states

Abstract

Unitarity violations were recently proposed as a cause of objective quantum state reduction. This complements proposals based on stochastic modifications of Schrodinger's equation, but also differs from them in several aspects. Here, we formalise the description of unitarity violations, and show that they generically imply models of dynamical quantum state reduction (DQSR) driven by colored noise. We present a formalism for exploring such models as well as a prescription for enforcing explicit norm-preservation, and we show that the resulting pure state dynamics is described by a modified von-Neumann Liouville equation which in a particular limit reduces to the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) master equations. We additionally show adherence to Born's rule emerging in the same limit from a physical constraint relating fluctuating and dissipating components of the model.