Entangled photons from para-positronium decay: Do coincidences from scattered photons imply a Bell state?

Paul Joos; Peter Kling

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arXiv · 2606.31726

Entangled photons from para-positronium decay: Do coincidences from scattered photons imply a Bell state?

Paul Joos·Peter Kling

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Abstract

Electron and positron can form a meta-stable bound state called positronium that decays via pair annihilation. We show how polarization-dependent Compton scattering can be used to verify that the two annihilation photons in the spin-zero case (para-positronium) are emitted in a maximally entangled Bell state. Our theoretical approach based on two-photon density matrices connects concepts from relativistic quantum electrodynamics and quantum information theory.

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Paul Joos, Peter Kling. 2026-06-30. Entangled photons from para-positronium decay: Do coincidences from scattered photons imply a Bell state?. https://arxiv.org/abs/2606.31726

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