{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,21]],"date-time":"2025-02-21T22:57:36Z","timestamp":1740178656985,"version":"3.37.3"},"reference-count":37,"publisher":"Verein zur Forderung des Open Access Publizierens in den Quantenwissenschaften","license":[{"start":{"date-parts":[[2017,7,14]],"date-time":"2017-07-14T00:00:00Z","timestamp":1499990400000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Quantum"],"abstract":"<jats:p>Macro-realism is the position that certain macroscopic observables must always possess definite values: e.g. the table is in some definite position, even if we do not know what that is precisely. The traditional understanding is that by assuming macro-realism one can derive the Leggett-Garg inequalities, which constrain the possible statistics from certain experiments. Since quantum experiments can violate the Leggett-Garg inequalities, this is taken to rule out the possibility of macro-realism in a quantum universe. However, recent analyses have exposed loopholes in the Leggett-Garg argument, which allow many types of macro-realism to be compatible with quantum theory and hence violation of the Leggett-Garg inequalities. This paper takes a different approach to ruling out macro-realism and the result is a no-go theorem for macro-realism in quantum theory that is stronger than the Leggett-Garg argument. This approach uses the framework of ontological models: an elegant way to reason about foundational issues in quantum theory which has successfully produced many other recent results, such as the PBR theorem.<\/jats:p>","DOI":"10.22331\/q-2017-07-14-13","type":"journal-article","created":{"date-parts":[[2017,7,14]],"date-time":"2017-07-14T09:30:20Z","timestamp":1500024620000},"page":"13","source":"Crossref","is-referenced-by-count":6,"title":["A Stronger Theorem Against Macro-realism"],"prefix":"10.22331","volume":"1","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5553-200X","authenticated-orcid":false,"given":"John-Mark A.","family":"Allen","sequence":"first","affiliation":[{"name":"Department of Computer Science, University of Oxford, Wolfson Building, Parks Road, Oxford, OX1 3QD, United Kingdom"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0570-0156","authenticated-orcid":false,"given":"Owen J. E.","family":"Maroney","sequence":"additional","affiliation":[{"name":"Faculty of Philosophy, University of Oxford, Radcliffe Humanities, Woodstock Road, Oxford, OX2 6GG, United Kingdom"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7879-8145","authenticated-orcid":false,"given":"Stefano","family":"Gogioso","sequence":"additional","affiliation":[{"name":"Department of Computer Science, University of Oxford, Wolfson Building, Parks Road, Oxford, OX1 3QD, United Kingdom"}]}],"member":"9598","published-online":{"date-parts":[[2017,7,14]]},"reference":[{"key":"1","doi-asserted-by":"crossref","unstructured":"A. J. Leggett and A. Garg, Quantum Mechanics versus Macroscopic Realism: Is the Flux There when Nobody Looks? Physical Review Letters 54(9), 857-860 (1985). http:\/\/dx.doi.org\/10.1103\/PhysRevLett.54.857.","DOI":"10.1103\/PhysRevLett.54.857"},{"key":"2","doi-asserted-by":"crossref","unstructured":"L. E. Ballentine, Realism and Quantum Flux Tunneling. 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