2021/01/21 by Tom Holden-Dye, Sandu Popescu, Holden-Dye, Tom +1
Physics and Astronomy · #Advanced Mathematical Theories and Applications #FOS: Physical sciences #Quantum Mechanics and Applications #Quantum Physics (quant-ph) #Relativity and Gravitational Theory #quant-ph
paper · pdf · doi:10.48550/arxiv.2101.08739
arxiv created 2021/01/21 · openalex publication_date 2021/01/21 · arxiv updated 2021/01/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
By studying the set of correlations that are theoretically possible between physical systems without allowing for signalling of information backwards in time, we here identify correlations that can only be achieved if the time ordering between the systems is fundamentally indefinite. These correlations, if they exist in nature, must result from non-classical, non-deterministic time, and so may have relevance for quantum (or post-quantum) gravity, where a definite global time might not exist.