Computational complexity

[John Kineman <***>]

Hi, The following link is to a Windows executable that installs SWARM
demos. This is the sytem Chris Langton developed at SFI.

ftp://ftp.swarm.org/pub/swarm/binaries/w32/swarmdemos-2.1.1.exe

I thought the 'dynamicgraph' demo gives a good idea of what is meant by
computational complexity in reference to the earlier discussion about
SFI, Langton, and von Neumann's approach. Some of the other demos don't
run on my machine and none are documented, so it wasn't clear what they
were about.

In the dynamicgraph simulation you see nodes moving by some ruleset and
forming relationships. From these rules various patterns form. The
patterns that form cannot be predicted by any calculation other than
running the iterative process, like a fractal.

I think the way to describe the difference between this kind of
simulation of what a "living" system behaves "like", i.e., similar
patterns, and what Rosen was saying is required to get at what it is
really doing, are several:
1. in how the probabilities are handled. Here they are assumed to be
random variations within some constraint - there is no "function" that
biases them.
2. in the rule set. While the agent-based approach takes a rule set and
derives unpredictable behavior and patterns from it, it is still
deterministic. The Rosennean approach suggests (requires) that the
organism is also capable of changing the rule set. This is a level of
functional feedback that isn't captured, of if it were, would also have
to be treated as a random change.

JJK

PS I tested this file in Windows XP and it installs OK. Not all the
demos work properly, but the dynamicgraph does. It does not contain any
virusus or worms. It may not run correctly on all systems, but it should
be safe to install. It can be uninstalled from the Windows Control
Panel, Add/Remove Programs menu.