How and why the wave function collapses after a measurement

TL;DR

This paper proposes that wavefunction collapse occurs due to a measurement-induced first order phase transition in the device, making the final states macroscopically distinct and unobservable in phase, without requiring additional postulates.

Contribution

It introduces a physical mechanism for wavefunction collapse based on phase transitions, removing the need for an extra postulate in quantum mechanics.

Findings

Collapse corresponds to a phase transition in the measuring device

Final states are macroscopically distinct and phase-invisible

The process is inherently irreversible

Abstract

We explain the collapse of the wavefunction with the notion that, in a measurement, the system observed nucleates a first order phase transition in the measuring device. The possible final states differ by the values of macroscopic observables, and their relative phase is therefore unobservable. The process is irreversible, but needs no separate postulate.