{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T00:39:22Z","timestamp":1759970362132,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,18]],"date-time":"2025-01-18T00:00:00Z","timestamp":1737158400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MCIN\/AEI\/10.13039\/ 501100011033","award":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"],"award-info":[{"award-number":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"]}]},{"name":"MCIN\/AEI\/10.13039\/501100011033","award":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"],"award-info":[{"award-number":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"]}]},{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"],"award-info":[{"award-number":["TED2021-129791B-I00","PID2022-137505NB-C22","2021SGR00856"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Directed networks are essential for representing complex systems, capturing the asymmetry of interactions in fields such as neuroscience, transportation, and social networks. Directionality reveals how influence, information, or resources flow within a network, fundamentally shaping the behavior of dynamical processes and distinguishing directed networks from their undirected counterparts. Robust null models are crucial for identifying meaningful patterns in these representations, yet designing models that preserve key features remains a significant challenge. One such critical feature is reciprocity, which reflects the balance of bidirectional interactions in directed networks and provides insights into the underlying structural and dynamical principles that shape their connectivity. This paper introduces a statistical mechanics framework for directed networks, modeling them as ensembles of interacting fermions. By controlling the reciprocity and other network properties, our formalism offers a principled approach to analyzing directed network structures and dynamics, introducing new perspectives and models and analytical tools for empirical studies.<\/jats:p>","DOI":"10.3390\/e27010086","type":"journal-article","created":{"date-parts":[[2025,1,21]],"date-time":"2025-01-21T06:53:32Z","timestamp":1737442412000},"page":"86","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Statistical Mechanics of Directed Networks"],"prefix":"10.3390","volume":"27","author":[{"given":"Mari\u00e1n","family":"Bogu\u00f1\u00e1","sequence":"first","affiliation":[{"name":"Department of Condensed Matter Physics, University of Barcelona, Mart\u00ed i Franqu\u00e8s 1, E-08028 Barcelona, Spain"},{"name":"University of Barcelona Institute of Complex Systems (UBICS), E-08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8779-5931","authenticated-orcid":false,"given":"M. \u00c1ngeles","family":"Serrano","sequence":"additional","affiliation":[{"name":"Department of Condensed Matter Physics, University of Barcelona, Mart\u00ed i Franqu\u00e8s 1, E-08028 Barcelona, Spain"},{"name":"University of Barcelona Institute of Complex Systems (UBICS), E-08028 Barcelona, Spain"},{"name":"Instituci\u00f3 Catalana de Recerca i Estudis Avan\u00e7ats (ICREA), Passeig Llu\u00eds Companys 23, E-08010 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Newman, M.E.J. 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