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arXiv · 2308.07412

Decay of entangled fermion pairs with post-selection

J. A. Aguilar-Saavedra
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Abstract

We consider a pair of unstable fermions in a spin-entangled state. After the decay of one fermion, a spin measurement is performed on the surviving partner, with a Stern-Gerlach experiment or similar. The measurement not only projects the spin of the surviving fermion, but is also physically equivalent to a spin projection for the decayed one -- even when it no longer exists. This post-selection effect would be experimentally accessible using muon pairs in a maximally-entangled state, produced either in the decay of a scalar particle, or in $e^+ e^-$ collisions at wide angles.

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J. A. Aguilar-Saavedra. 2023-08-14. Decay of entangled fermion pairs with post-selection. https://arxiv.org/abs/2308.07412

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