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arXiv · 2504.07030

Decoherence effects in entangled fermion pairs at colliders

Rafael Aoude·Alan J. Barr·Fabio Maltoni·Leonardo Satrioni
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Abstract

Recent measurements at the Large Hadron Collider have observed entanglement in the spins of $t\bar t$ pairs. The effects of radiation, which are expected to lead to quantum decoherence and a reduction of entanglement, are generally neglected in such measurements. In this work we calculate the effects of decoherence from various different types of radiation for a maximally entangled pair of fermions -- a bipartite system of qubits in a Bell state. We identify the Kraus operators describing the evolution of the open quantum system with the integrated Altarelli-Parisi splitting functions.

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Rafael Aoude, Alan J. Barr, Fabio Maltoni, Leonardo Satrioni. 2025-04-09. Decoherence effects in entangled fermion pairs at colliders. https://arxiv.org/abs/2504.07030

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