title: Alternative paradigm for physical computing.
abstract: We identify a different class of physical systems that are able to form universal logic gates. By analogy with Si(100) surface dimers, we present a model to analyze the trajectories of the fixed points (interpreted as logic states) under variation of the basic parameters. Using the perspective of catastrophe theory, we show that information processing is the result of cycling the parameters of such systems through a path containing a cusp-type catastrophe. We apply this analysis to the construction of an example based on magnetic memory.
authors.affiliation: Department of Physics, Massachusetts Institute of Technology, Cambridge 02139, USA.
authors.forename: Ian
authors.initials: I
authors.lastname: Appelbaum
authors.forename: J D
authors.initials: JD
authors.lastname: Joannopoulos
authors.forename: V
authors.initials: V
authors.lastname: Narayanamurti