

SCS
DISTINGUISHED LECTURE
13April2000
ED FREDKIN
DIGITAL
MECHANICS (DM)
4:00
pm, Wean Hall 7500
3:45
pm  Refreshments Outside the Auditorium
Contact: Vivian Lee, 2682572
or vl@cs.cmu.edu
ABSTRACT
Digital Mechanics
(DM) is the name we give to models of microscopic physics that are
entirely discrete and finite. We will illustrate the power of DM
models by defining a particular model, assigning a small number
of properties to the elements of the model, and then deriving a
large number of properties from the model that are reminiscent of
Physics. In particular, we will start with a simple binary 3+1D
lattice, where the time dimension has extent 2 and some further
complexity. We then define just one conserved element, the bit;
B. You can think of it as a binary digit: 1 or 0. However the 1's
(and the 0's) are both conserved. Of course, there must be a rule
that determines what happens to the Bs. In this model there are
3 fundamental units, B, Length and Time.
That's it, BL&T; that's
all we put into the model. Here's what we get out: We will show
in simple terms exactly how the model might represent stuff very
similar to what we know in physics. To understand and absorb all
these explanations, the listeners must tolerate an inordinate amount
of hand waving and in addition must be able to temporarily suspend
many of their most cherished beliefs. We will explain the DM version
of space, time, energy, momentum, force, charge, temperature, QCD
color, why (within the model) there are particles and antiparticles,
why conservation laws, how things move, why there is CPT parity,
how angular isotropy and relativity arise despite angular anisotropy
and an absolute reference frame at the most microscopic level. Finally
why so many fundamental numbers (as are found in physics) are bound
to appear from such DM models. If you can force yourself to swallow
a byte of the BL&T theory of physics, you might not like it, but
it might be good for you.
Speaker Biography
Ed Fredkin has had a
long interest in Computer Science and Physics. He has been on the
faculties of MIT in Computer Science, Caltech and Boston University
in Physics. While at MIT he served as the Director of LCS. Fredkin
has also had an association with Carnegie Mellon for a number of
years. His current academic interests are in Digital Mechanics;
the study of discrete models of fundamental process in Physics.

