Reaction-Diffusion Computers


  • Andrew Adamatzky, Faculty of Computing, Engineering and Mathematical Sciences, University of the West of England, Bristol, UK
  • Benjamin De Lacy Costello, Faculty of Applied Sciences, University of the West of England, Bristol, UK
  • Tetsuya Asai, School of Information Science and Technology, Hokkaido University, Sapporo, Japan

The book introduces a hot topic of novel and emerging computing paradigms and architectures -computation by travelling waves in reaction-diffusion media. A reaction-diffusion computer is a massively parallel computing device, where the micro-volumes of the chemical medium act as elementary few-bit processors, and chemical species diffuse and react in parallel. In the reaction-diffusion computer both the data and the results of the computation are encoded as concentration profiles of the reagents, or local disturbances of concentrations, whilst the computation per se is performed via the spreading and interaction of waves caused by the local disturbances. The monograph brings together results of a decade-long study into designing experimental and simulated prototypes of reaction-diffusion computing devices for image processing, path planning, robot navigation, computational geometry, logics and artificial intelligence. The book is unique because it gives a comprehensive presentation of the theoretical and experimental foundations, and cutting-edge computation techniques, chemical laboratory experimental setups and hardware implementation technology employed in the development of novel nature-inspired computing devices.

Key Features:

- Non-classical and fresh approach to theory of computation.
- In depth exploration of novel and emerging paradigms of nature-inspired computing.
- Simple to understand cellular-automata models will help readers/students to design their own computational experiments to advance ideas and concepts described in the book .
- Detailed description of receipts and experimental setups of chemical laboratory reaction-diffusion processors will make the book an invaluable resource in practical studies of non-classical and nature-inspired computing architectures .
- Step by step explanations of VLSI reaction-diffusion circuits will help students to design their own types of wave-based processors.

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Academics and researchers and graduate students in computer science, chemistry, physics, electrical engineering, artificial intelligence, mathematics, software engineering. Professionals in computer architectures and high-performance computing, smart materials and structues, nature-inspired robotics. The book is aimed to be a valuable supplementary reading for graduate students.


Book information

  • Published: October 2005
  • Imprint: ELSEVIER
  • ISBN: 978-0-444-52042-5


"(The authors) plans for a chemical brain might be over-ambitious - but not completely crazy. (...) (they are) likely to uncover new ideas that could help create better processors or reveal something about the way our brain works." New Scientist, 26 march 2005, p. 33

Table of Contents

1 Non-linear chemistry meets non-classical computation.
1.1 What is a chemical processor?.
1.2 Overview of chemical processors.
1.3 Other chemical.
1.4 Current state of reaction diffusion.
2 Geometrical computation: Voronoi diagram and skeleton.
2.1 Voronoi diagram.
2.2 Time-to-space mapping .
2.3 Cellular-automaton Voronoi diagram.
2.4 Chemical Processors for Voronoi diagram computation .
2.5 Voronoi diagrams in chemical processors.
2.6 When computations go wrong!
2.7 Unstable processors .
2.8 Secondary Voronoi diagrams.
2.9 Controllability of secondary Voronoi diagrams.
2.10 Skeleton of planar shape.
2.11 Chemical processors for skeleton computation.
2.12 Mechanics of skeletonization.
2.13 Computing skeletons of geometric shapes.
2.14 Multi-tasking in chemical processors.
2.15 Conclusion.
3 Logical circuits in chemical media.
3.1 Logical gates in precipitating medium.
3.2 Collision-based computing in excitable media.
3.3 Laboratory prototype of collision-based computer.
3.4 Hexagonal reaction-diffusion automaton.
3.5 Conclusion.
4 Reaction-diffusion controllers for robots.
4.1 Robot taxis controlled by a Belousov-Zhabotinsky medium.
4.2 Path planning.
4.3 Controlling a robotic hand.
4.4 Conclusion.
5 Programming reaction-diffusion processors.
5.1 How to program reaction-diffusion computers?
5.2 Programming with reaction rates.
5.3 Programming with excitability.
5.4 Conclusion.
6 Silicon Reaction-Diffusion Processors.
6.1 Modelling Reaction-Diffusion LSI circuits.
6.2 Digital Reaction-Diffusion Chips.
6.3 Analog Reaction-Diffusion Chips.
7 Minority-Carrier Reaction-Diffusion Device.
7.1 RD Computing Device with p-n-p-n Diode.
7.2 Numerical Simulation Results.
7.3 Computing in RD semiconductor devices.
7.4 Conclusion.
8 Single-Electron Reaction-Diffusion Devices.
8.1 Constructing electrical analog of reaction-diffusion systems.
8.2 Spatiotemporal dynamics produced by the single-electron RD system.
8.3 Toward actual RD devices.
9 Non-constructibility: From Devil's Advocate.
9.1 Computing with singularities .
9.2 Voronoi diagram is not invertible.
9.3 Conclusion.