# Photon-Detector Entanglement by interference at beam splitter (Collapse and spontaneous superposition breaking)

## TL;DR

This paper proposes a realistic experiment involving single photon interference at a beam splitter to study entanglement and spontaneous superposition breaking, offering a consistent model of quantum measurement and collapse.

## Contribution

It introduces a novel experimental setup and a model where collapse is viewed as spontaneous symmetry breaking within quantum mechanics.

## Key findings

- Demonstrates entanglement between photon and detector systems.
- Models collapse as spontaneous symmetry breaking.
- Provides a consistent framework for quantum measurement.

## Abstract

In this work we suggest an original, realistic and simple, form of the experiment of interference of single photon at beam splitter. Here quantum entanglement (Schrodinger cat effect) between photon and photon trajectories detector (which includes two same simple two-level systems) is studied. It admits a consistent model of the detection or measurement procedure. Concretely here (self-)collapse at detector is consistently treated as the spontaneous (non-dynamical) breaking (effective hiding) of the unitary symmetry (superposition or entanglement) of quantum mechanical dynamics. It can be considered as an especial case of the general formalism of the spontaneous symmetry breaking.

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Source: https://tomesphere.com/paper/0909.2105