Summary: Modeling Living Systems
School of Computing Science, Newcastle University, Claremont Tower, Claremont Road,
Newcastle upon Tyne, NE1 7RU, United Kingdom
Abstract. A fundamental issue of evolution of life is the emergence and
maintenance of self-referential autocatalytic systems (e.g. living cells). In this
paper the problem is analyzed from a computational perspective. It is proposed
that such systems have to be infinite autocatalytic systems, which can be
considered equivalent to Turing machines. The implication of this is that
searching for finite autocatalytic systems is likely to not be successful, and any
such finite system would be maintainable only in a highly stable environment.
The infiniteness of autocatalytic systems also implies that top-down search for
the simplest living system is likely to stop at relatively complex cells that are
still able to provide a realization of infinite autocatalytic systems.
Keywords: autocatalysis, computation, formal model, self-reference, infinite
The questions of what makes living systems alive and how to create live systems are