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arXiv · 2511.10197

High-Energy Decays and Weak Quantum Measurements

Alan J. Barr
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Abstract

High-energy particle decays naturally realise informationally weak measurements of quantum spin. Decay kinematics act as continuous pointer variables whose overlapping angular distributions encode partial, non-projective information about the parent spin state. Ensemble averages of these pointers yield weak values, linking collider spin-density reconstruction to Aharonov-Vaidman measurement theory. This framework unifies spin tomography, entangled-decay correlations, and spin-correlation algorithms, showing that relativistic decays realise informationally weak measurements of spin and suggesting new ways to probe coherence and interference in high-energy processes.

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Alan J. Barr. 2025-11-13. High-Energy Decays and Weak Quantum Measurements. https://arxiv.org/abs/2511.10197

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