From Utopian to Genuine Unconventional Computers

223 Pages·2006·2.62 MB·English

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Luniver Press
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Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
From Utopian to Genuine
Unconventional Computers
Splendeurs et mis`eres du calcul peu usuel
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
.
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
Andrew Adamatzky and Christof Teuscher
Editors
From Utopian to Genuine
Unconventional Computers
Splendeurs et mis`eres du calcul peu usuel
Luniver Press
2006
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
Published by Luniver Press
Frome BA11 6TT United Kingdom
British Library Cataloguing-in-Publication Data
A catalogue record for this book is available from the British Library
From Utopian to Genuine Unconventional Computers: Splendeurs et
mis`eres du calcul peu usuel
Copyright (cid:1)c Luniver Press 2006
All rights reserved. This book, or parts thereof, may not be reproduced
in any form or by any means, electronic or mechanical, including photo-
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without permission in writing from the copyright holder.
ISBN-10: 0-9551170-9-7
ISBN-13: 978-0-9551170-9-1
1st edition
While every attempt is made to ensure that the information in this
publication is correct, no liability can be accepted by the authors or
publishersforloss,damageorinjurycausedbyanyerrorsin,oromission
from, the information given.
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
Editorial
“... it is stimulating to realize the mathematical conditions of the prob-
lem by corresponding physical devices, or rather, to consider the math-
ematical problem as an interpretation of a physical phenomenon. The
existenceofthephysicalphenomenonthenrepresentsthesolutionofthe
mathematical problem” — this is how, back in 1941, Richard Courant
andHerbertRobbins1 outlined,yetnotexplicitlynamedunconventional
computing.Nowadaysunconventionalcomputing includes,butisnotlim-
ited to physics of computation, chemical and bio-molecular computing,
cellular automata, non-classical logics, amorphous computing, and me-
chanical computation.
It is a vibrant and interdisciplinary field aimed at developing new
algorithmic paradigms and novel physical computing substrates. While
thelasttwentyyearsweremainlydominatedbyabstractunconventional
machines, there is an increasing effort in building genuine realizations.
Compared to simulations of abstract machines, genuine machines gener-
ally allow to fully and directly exploit the computational capabilities —
including the usually massive parallelism — of the physics or chemistry
of the underlying substrate.
In organising the 2006 workshop From Utopian to Genuine Uncon-
ventionalComputers:Splendeursetmis`eresducalculpeuusuel2,wewere
eager to resurrect decades old ideas on how to embed and to do com-
putation in physical substrates. We wanted to bring to light working
prototypes of unconventional computers akin to Riemann’s experiments
on the flow of electricity in thin metallic sheet, akin to Lord Kelvin’s
analog differential analyzer, and akin to Plateau’s experiments on the
calculation of the surface of the smallest area bounded by a given closed
contour. We did not exactly get what we were hoping for, nevertheless,
the nine contributed papers to this volume are exciting enough to be
flagshipsofthefield.Ourthirstforexperimentalprototypesandgenuine
1 Courant R. and Robbins H. What is Mathematics? (Oxford University
Press, 1941).
2 The workshop was organized as part of the 5th International Conference
on Unconventional Computation, UC 2006, which was held Sep 4–8, 2006,
at the University of York, UK. We would like to express our gratitude to
the members of the workshop program committee, who did a great job in
vigorously reviewing every submission and ensuring an exceptional quality
oftheacceptedpapers.We’realsoverygratefultotheUC’06organizersfor
giving us the opportunity to hold this workshop!
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
VI
implementationsofnon-classicalcomputingdevicesisindeedsatisfiedby
the majority of the contributions in this volume. In addition, we have
alsodecidedtoincludeanumberofmoretheoreticalpapersofparticular
interest.
Intheveryfirstchapter,“OndigitalVLSIcircuitsexploitingcollision-
based fusion gates”, Yamada, Motoike, Asai, and Amemiya propose a
novelmethodtodesignVLSIcircuits,basedonfusiongates,whichitself
was discovered by designing logical circuits in excitable chemical media.
Theyshowanefficientwaytobuildlogicgates,whichwouldatthesame
time allow them to operate at high speed and low power.
The ultimate goal of Larry Bull and his collaborators is to build
a chemical neural network in Belousov-Zhabotinsky media. The first
stage of the project — which consists in controlling and adapting sub-
excitable chemical medium — is addressed in their contribution “To-
wards machine learning control of chemical computers”. They do not
employ geometrically-constraint media but use the light-sensitivity of
thesystemtoimposedynamicalstructuresofquasi-neuronalconnections
instead. They then apply machine learning to direct wave fragments to
an arbitrary position, and thus to solve a specific task.
Nicolas Glade gives us a biochemist’s view on computation. He ex-
plores micro-tubules as a media for in vitro computation. The computa-
tions are based on ”chemical collisions” between micro-tubules. No defi-
nite computation schemes are provided, however, experimental evidence
discussed suggests a huge computational potential with micro-tubules.
Yet another unconventional approach for a potential computing sys-
tem is presented by Greenman, Ieropolous, and Melhuish: the imple-
mentationofPavlovianreflexesinbacterialfilms.Weenvisionthattech-
niques outlined in “Perfusion anodophile biofilm electrodes and their
potentialforcomputing”willbeusedinfuturedesignsofbacteria-based
controllers for autonomous robots, which are powered by bacterial cells.
Finally, in the last more practically-oriented contribution, Murphy
et al. implement physical sorting by using various methods, such as gel
electrophoresis,massspectroscopy,andchromatography.Amongstother
wonderful things, their paper “Implementations of a model of physical
sorting” tells us again that computation in physics and Nature is ubiq-
uitous.
Universal computation is a key concept in computer science since its
beginnings in the early fifties. In his contribution “Conventional or un-
conventional: Is any computer universal?”, Selim Akl discusses different
evolving computational paradigms.
Wiesner and Crutchfield explore the language diversity of quantum
finite-state generators — which occupy the lowest level of the still par-
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
VII
tially unknown hierarchy of quantum computation — and show that
deterministic quantum finite-state generators have a larger language di-
versitythantheirclassicalanalogstochasticfinite-stategenerators.Con-
cepts studied in Wiesner and Crutchfield’s “Language diversity of mea-
sured quantum processes” are currently rather far from any real-world
implementation, however, they do certainly stimulate our brains with
the esthetic of theoretical aspects.
Collision-based computing is a well-known unconventional comput-
ing paradigm, traced back to Conway’s Game of Life, Fredkin-Toffoli’s
conservative logic, and Steiglitz’s particle machines. In “Logic circuits
in a system of repelling particle”, William Stevens develops a kinematic
modelofmovabletilesinatwo-dimensionalenvironmentandshowshow
dual-rail logic gates can be constructed.
Finally, De Vos and Van Rentergem study in “From group theory
to reversible computer” the building-blocks for reversible computing ar-
chitectures and show that a particular set can be used to synthesize
arbitrary reversible circuits. They have also built and tested silicon im-
plementations of adder circuits.
We certainly hope that our readers will enjoy the wide variety of
non-classical computing devices — be it chemical, molecular, electronic,
orquantum—presentedinthistimelyvolume.Thecontributionsattest
that there are almost no limits with regards to what physical substrates
are used and how computations are performed.
“I don’t think God’s a computation. But exactly why not?”, Rudy
Rucker wrote3.
June 2006 Andy Adamatzky and Christof Teuscher
Workshop Chairs,
Bristol and Los Alamos
3 Rudy Rucker, The Lifebox, The Seashell, and The Soul. Thunder’s Mouth
Press, New York, 2006.
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
Referees
Andrew Adamatzky, University of the West of England, UK
Tetsuya Asai, Hokkaido University, Japan
Ben de Lacy Costello, University of the West of England, UK
Peter Dittrich, Friedrich-Schiller-University Jena, Germany
Jerzy Gorecki, Polish Academy of Science, Poland
Norman Margolus, MIT Artificial Intelligence Laboratory, USA
Genaro Martinez, National University of Mexico, Mexico
Julian F. Miller, University of York, UK
Jonathan W. Mills, Indiana University, USA
Kenichi Morita, Hiroshima University, Japan
Ikuko Motoike, Future University Hakodate, Japan
Ferdinand Peper, Kansai Advanced Research Center, Japan
Ken Steiglitz, Princeton University, USA
Susan Stepney, University of York, UK
Christof Teuscher, Los Alamos National Laboratory, USA
Tommaso Toffoli, Boston University, USA
Hiroshi Umeo, Osaka Electro-Communication University, Japan
Damien Woods, University College Cork, Ireland
Thomas Worsch, Universitaet Karlsruhe, Germany
Kenichi Yoshikawa, Kyoto University, Japan
Klaus-Peter Zauner, University of Southampton, UK
.
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091
Table of Contents
From Utopian to Genuine Unconventional
Computers
On digital VLSI circuits exploiting collision-based fusion gates... 1
Kazuhito Yamada, Tetsuya Asai, Ikuko N. Motoike, Yoshihito
Amemiya
Towards machine learning control of chemical computers........ 17
Adam Budd, Christopher Stone, Jonathan Masere, Andrew
Adamatzky, Ben De Lacy Costello, Larry Bull
Existence and persistence of microtubule chemical trails — a
step toward microtubule collision-based computing ............. 37
Nicolas Glade
Perfusion anodophile biofilm electrodes and their potential for
computing ................................................ 67
John Greenman, Ioannis Ieropoulos, Chris Melhuish
Implementations of a model of physical sorting ................ 79
Niall Murphy, Thomas J. Naughton, Damien Woods, Beverley
Henley, Kieran McDermott, Elaine Duffy, Peter J. M. van der
Burgt, Niamh Woods
Conventional or unconventional: Is any computer universal?
Rigueurs et revers du calcul universel ........................ 101
Selim G. Akl
Language diversity of measured quantum processes............. 137
Karoline Wiesner, James P. Crutchfield
Logic circuits in a system of repelling particles................. 157
William M. Stevens
From group theory to reversible computers .................... 183
Alexis De Vos, Yvan Van Rentergem
Index..................................................... 209
Adamatzky A. and Teuscher C. (Eds.) From Utopian to Genuine Unconventional Computers (Luniver Press, 2006)
ISBN-10: 0955117097 ISBN-13: 978-0955117091