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The following paper is available by public ftp.

     Dynamics, Computation, and the ``Edge of Chaos'': A Re-Examination
	
         Melanie Mitchell    James P. Crutchfield    Peter T. Hraber
        Santa Fe Institute        UC Berkeley       Santa Fe Institute  

              Santa Fe Institute Working Paper 93-06-040

                                Abstract

In this paper we review previous work and present new work 
concerning the relationship between dynamical systems theory and computation. 
In particular, we review work by Langton (1990) and Packard (1988) on the 
relationship between dynamical behavior and computational capability in 
cellular automata (CA).  We present results from an experiment similar to 
the one described in Packard (1988), that was cited there as evidence for 
the hypothesis that rules capable of performing complex computations are most 
likely to be found at a phase transition between ordered and chaotic behavioral
regimes for CA (the "edge of chaos").  
Our experiment produced very different results from the original
experiment, and we suggest that the interpretation of the original results is 
not correct.  We conclude by discussing general issues related to dynamics,
computation, and the "edge of chaos" in cellular automata.  

To appear in G. Cowan, D. Pines, and D. Melzner (editors), 
_Integrative Themes_.  Santa Fe Institute Stuides in the
Sciences of Complexity, Proceedings Volume 19.  Reading, MA: Addison-Wesley.  

Note: This paper is a much shorter version of our paper "Revisiting the
Edge of Chaos" (SFI Working Paper 93-03-014, announced previously on this
newsgroup). It contains an expanded review of previous work on relationships 
between dynamical systems theory and computation.  

To obtain an electronic copy:

	ftp santafe.edu
	login: anonymous
	password: <your email address>
	cd /pub/Users/mm
	binary
	get sfi-93-06-040.ps.Z 
	quit

Then at your system:

	uncompress sfi-93-06-040.ps.Z
	lpr -P<printer-name> sfi-93-06-040.ps


To obtain a hard copy (only if you cannot obtain an electronic copy), send a 
request to dlu at santafe.edu.