Toy Model Challenging Prevailing Definitions of Classicality

2024/12/11 by Irene Valladares Duque, Philipp Strasberg, Duque, Irene Valladares +1 · 1 voice
Computer Science · Physics and Astronomy · #Artificial Intelligence in Games #FOS: Physical sciences #Quantum Physics (quant-ph) #quant-ph

paper · pdf · doi:10.48550/arxiv.2412.08444

openalex publication_date 2024/12/11 · arxiv published 2024/12/11 · openalex created_date 2025/10/10 · arxiv updated 2025/11/19 · openalex updated_date 2026/07/28

Abstract

We analyze a toy model that obeys environmentally induced decoherence and quantum Darwinism and satisfies the decoherent histories criterion and Leggett-Garg inequalities with respect to the pointer basis. Yet, the resulting "classical" dynamics are extremely fragile and recohere after a seemingly innocent control operation. This challenges the idea that classical behaviour or the Multiverse branches can be identified by looking at the universal wave function alone. It also demonstrates that quantum Darwinism is compatible with strong non-Markovianity. Possible solutions related to Markovianity, non-integrability and an operational definition of pointer states are briefly discussed.

Discussions

• Hello community. Using my first post here for some shameless self-advertising of a cute little paper (arxiv.org/abs/2412.08444) explaining subtleties and pitfalls of decoherence and the emergence of c [bsky, 2 points, 0 comments]

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