{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T06:36:42Z","timestamp":1776321402236,"version":"3.50.1"},"reference-count":65,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,3,3]],"date-time":"2023-03-03T00:00:00Z","timestamp":1677801600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100011730","name":"Templeton World Charity Foundation","doi-asserted-by":"publisher","award":["TWCF-2020-20526"],"award-info":[{"award-number":["TWCF-2020-20526"]}],"id":[{"id":"10.13039\/501100011730","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Originally conceived as a theory of consciousness, integrated information theory (IIT) provides a theoretical framework intended to characterize the compositional causal information that a system, in its current state, specifies about itself. However, it remains to be determined whether IIT as a theory of consciousness is compatible with quantum mechanics as a theory of microphysics. Here, we present an extension of IIT\u2019s latest formalism to evaluate the mechanism integrated information (\u03c6) of a system subset to discrete, finite-dimensional quantum systems (e.g., quantum logic gates). To that end, we translate a recently developed, unique measure of intrinsic information into a density matrix formulation and extend the notion of conditional independence to accommodate quantum entanglement. The compositional nature of the IIT analysis might shed some light on the internal structure of composite quantum states and operators that cannot be obtained using standard information-theoretical analysis. Finally, our results should inform theoretical arguments about the link between consciousness, causation, and physics from the classical to the quantum.<\/jats:p>","DOI":"10.3390\/e25030449","type":"journal-article","created":{"date-parts":[[2023,3,6]],"date-time":"2023-03-06T03:22:05Z","timestamp":1678072925000},"page":"449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Computing the Integrated Information of a Quantum Mechanism"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1000-9917","authenticated-orcid":false,"given":"Larissa","family":"Albantakis","sequence":"first","affiliation":[{"name":"Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA"},{"name":"Association for Mathematical Consciousness Science, 80539 Munich, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1890-0827","authenticated-orcid":false,"given":"Robert","family":"Prentner","sequence":"additional","affiliation":[{"name":"Association for Mathematical Consciousness Science, 80539 Munich, Germany"},{"name":"Munich Center for Mathematical Philosophy, Ludwig-Maximilians-University, 80539 Munich, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2054-7551","authenticated-orcid":false,"given":"Ian","family":"Durham","sequence":"additional","affiliation":[{"name":"Association for Mathematical Consciousness Science, 80539 Munich, Germany"},{"name":"Department of Physics, Saint Anselm College, Manchester, NH 03102, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Oizumi, M., Albantakis, L., and Tononi, G. 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