C. Horsman, Susan Stepney, Viv Kendon.
When does an unconventional substrate compute?.

In Unconventional Computation and Natural Computation 2013, Milan, Italy, July 2013. LNCS 7956:209-219. Springer, 2013

Abstract:

Many diverse substrates are proposed for unconventional computation, from relativistic and quantum systems, to chemical reactions and slime moulds. But what does it mean to say that such substrates are specifically computing, as opposed to merely performing the physical processes of that substrate?

@inproceedings(SS-UCNC14,
  author = "C. Horsman and Susan Stepney and Viv Kendon",
  title = "When does an unconventional substrate compute?",           
  crossref = "UCNC14"
)

@proceedings(UCNC14,
  title = "13th International Conference on Unconventional Computation and Natural Computation 
            UCNC 2014), London, Ontario, Canada, July 2014, Poster Proceedings",
  booktitle = "13th International Conference on Unconventional Computation and Natural Computation 
            UCNC 2014), London, Ontario, Canada, July 2014, Poster Proceedings",
  series = "Technical Report",
  volume = 758,
  publisher = "University of Western Ontario",
  year = 2014
)