[comp.ai] Boolean Cube

firth@sei.cmu.edu (Robert Firth) (10/13/89)

Friends

Would you kindly permit an interloper to ask a
question that is beyond his expertise.  In a
recent publication, I found this

	"...the Boolean cube, a geometric
	 model for computer processing in
	 the field of artificial intelligence."

Unfortunately, I've never heard of the 'Boolean
cube', and have so far been unable to find any
reference to it.

Couls one of you more familiar with AI be so
kind as to email me a definition, or a reference,
or anything else helpful?

Thanks in advance.

cjoslyn@bingvaxu.cc.binghamton.edu (Cliff Joslyn) (10/13/89)

In article <4469@bd.sei.cmu.edu> you write:
>	"...the Boolean cube, a geometric
>	 model for computer processing in
>	 the field of artificial intelligence."

Check any text on discrete structures or algebra theory.  A cube of
dimension n, denoted Cn, is the cross product of the set { 0, 1 } n
times.  For example, 

C3 = { ( 0, 0, 0 ), ( 0, 0, 1 ), ( 0, 1, 0 ), ... , ( 1, 1, 1 ) }

This is the simple three dimensional cube we're used to (plot the points
in 3-space).  C2 is just the unit square, C1 the unit interval.  C4 is a
4-d hypercube, etc. 

I believe that the reference to AI is that in multiprocessing systems
cubes are useful architectures.  The "Hypercube" computer is built with
this architecture.  Also, check out Penti Kanerva, _Sparse Distributed
Memory_, an excellent book on the geometry of { 0, 1 }^n spaces for
large n and their significance not only for AI, but many complex systems
with strings composed of symbols with limitted variation but long length
(like genes). 

-- 
O---------------------------------------------------------------------->
| Cliff Joslyn, Cybernetician at Large
| Systems Science, SUNY Binghamton, cjoslyn@bingvaxu.cc.binghamton.edu
V All the world is biscuit shaped. . .