{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,11]],"date-time":"2026-02-11T18:09:13Z","timestamp":1770833353843,"version":"3.50.1"},"reference-count":80,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2012,10,17]],"date-time":"2012-10-17T00:00:00Z","timestamp":1350432000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Classical computing has well-established formalisms for specifying, refining, composing, proving, and otherwise reasoning about computations. These formalisms have matured over the past 70 years or so. Unconventional Computing includes the use of novel kinds of substrates\u2013from black holes and quantum effects, through to chemicals, biomolecules, even slime moulds\u2013to perform computations that do not conform to the classical model. Although many of these unconventional substrates can be coerced into performing classical computation, this is not how they \u201cnaturally\u201d compute. Our ability to exploit unconventional computing is partly hampered by a lack of corresponding programming formalisms: we need models for building, composing, and reasoning about programs that execute in these substrates. What might, say, a slime mould programming language look like? Here I outline some of the issues and properties of these unconventional substrates that need to be addressed to find \u201cnatural\u201d approaches to programming them. Important concepts include embodied real values, processes and dynamical systems, generative systems and their meta-dynamics, and embodied self-reference.<\/jats:p>","DOI":"10.3390\/e14101939","type":"journal-article","created":{"date-parts":[[2012,10,17]],"date-time":"2012-10-17T11:14:50Z","timestamp":1350472490000},"page":"1939-1952","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Programming Unconventional Computers: Dynamics, Development, Self-Reference"],"prefix":"10.3390","volume":"14","author":[{"given":"Susan","family":"Stepney","sequence":"first","affiliation":[{"name":"York Centre for Complex Systems Analysis, University of York, York, YO10 5DD, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2012,10,17]]},"reference":[{"key":"ref_1","unstructured":"Zalta, E.N. The Stanford Encyclopedia of Philosophy, [2008 ed.]. 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