* NOTE ROOM CHANGE *


		University of Hertfordshire Algorithms Group

	    Mathematical Computer Science & Applications Seminar

       "Time, Sequential Machines, and Feedback-free Decompositions"

		      Prof. Chrystopher L. Nehaniv
	 (School of Computer Science, University of Hertforshire)

			24 May 2007 (Thursday)
			  Seminar Room C450
		    Hatfield, College Lane Campus
				1-3 pm

	     Coffee/tea and biscuits should be available.

			     All Welcome!



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Abstract:

This seminar explains the notion of sequential machine --- which have
"real-time" on-line behaviour in contrast to the off-line computation
of Turing machines --- and their connection to circuits and
semigroups.  The Krohn-Rhodes Theorem gives a method for constructing
any finite state sequential machine in a feedback-free, series-parallel
manner from certain irreducible components, corresponding to algebraic
invariants of the sequential machine.

Semigroups are models of time and of computation. If time permits, some
of Rhodes' ideas on these algebraic structures in relation to time,
space, science and religion will be presented.

Reference "The Wild Book":

Applications of Automata Theory and Algebra with the Mathematical
Theory of Complexity to Finite-State Physics, Biology, Philosophy, and
Games, by John L. Rhodes, editor: C. L. Nehaniv, foreword by Morris W.
Hirsch, World Scientific Press, to appear 2007.

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Seminar Abstracts:
http://homepages.feis.herts.ac.uk/~nehaniv/mcsa/