Penny Faulkner Rainford
Algebraic approaches to artificial chemistries
PhD thesis, University of York, 2018


We have developed a new systematic framework, MetaChemisty for the description of artificial chemistries (AChems). It encompasses existing systems. It has the flexibility and complexity to allow for new features and new systems. A joint description language will allow comparisons to be drawn between systems. This will allow us to write metrics and benchmarks for artificial chemistries. It also enables us to combine existing systems in different ways to give a wealth of more complex and varied systems. We will be able to build novel chemistries quicker through reuse of code and features between chemistries allowing new chemistries to start from a more complex base line.We have also developed an algebraic artificial chemistry, Jordan Algebra Artificial Chemistry (JA AChem). This chemistry is based on existing algebra which is leverage to ensure features such as isomers and isotopes are possible in our system. The existence of isotopes leads naturally to the existence of elements for this chemistry. It is a chemistry with both constructive and destructive reactions making it a good candidate for further study as an open-ended system. We analyse the effect of changing probabilistic processes in JA AChem by modifying the probability spawning functions that control them. We also look at the algebraic properties of these probability spawning functions. We have described Swarm Chemistry, Sayama (2009),in the MetaChem showing it is at least more expressive than the previous framework for artificial chemistries, Dittrich et al. (2001).We use the framework to combine two artificial chemistries using a simple environment link structure to produce eight new modular AChems with a modular approach. This link structure requires minimal addition to existing code for artificial chemistry systems and no modification to most modules.

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