Quantum state reduction of general initial states through spontaneous unitarity violation

TL;DR

This paper proposes models where spontaneous unitarity violation explains quantum measurement, showing that Born's rule naturally emerges, thus addressing a foundational problem in quantum mechanics.

Contribution

It introduces a family of models for spontaneous unitarity violation applicable to general initial states, demonstrating the emergence of Born's rule.

Findings

Born's rule emerges spontaneously in the models

Models apply to arbitrary initial superpositions

Unitarity violation leads to measurement phenomena

Abstract

The inability of Schrodinger's unitary time evolution to describe measurement of a quantum state remains a central foundational problem. It was recently suggested that the unitarity of Schrodinger dynamics can be spontaneously broken, resulting in measurement as an emergent phenomenon in the thermodynamic limit. Here, we introduce a family of models for spontaneous unitarity violation that apply to generic initial superpositions over arbitrarily many states, using either single or multiple state-independent stochastic components. Crucially, we show that Born's probability rule emerges spontaneously in all cases.