# Clarification of Terms (was RE: What We Can Know About the World)

Russell submits the following as clarifications:

> An event is a particular set of coordinates (t,x,y,z) in 4D
> spacetime. This is how it is used in GR, anyway.
>
> An observer moment is a set of constraints, or equivalently
> information known about the world (obviously at a moment of time).
> It [the observer moment] corresponds the the "state" vector \psi
> of quantum mechanics.

and Stephen inquires

> Hi Russell,
>     A possibly related question. Given your definition of events and OMs,
> does it not seem that they complement each other, assuming that events have
> more quatities associated, such as 4-momentum-energy?

Well, Russell did also say that OMs and events seemed to him about as
alike as chalk and cheese. It's starting to look that way:

I quote Hal:

Calling them [causal patterns] "observer moments" seems
to be a bit of a stretch, given the enormous number of
orders of magnitude difference between what we would
normally recognize as a conscious OM and one of these
trivial ones [e.g. a 302-neuron nematode OM].

So, alas, it seems that the firmly established meanings of
"event" and "observer moment" can't really be said to be at
all the same thing. (Folks like Russell and Hal have been
using the term "OM" for years and years, and "event" has
a pretty standard meaning in physics.) Observer moments have
to do with something conscious (and, evidently, pretty complex).
And of course, as Hal wrote later on, consciousness exists on
a gray scale.

Lee

P.S. In normal physics an event, as Russell says, is associated
with coordinates. Nonetheless I, for one, had always supposed
that indeed something was happening there, e.g., a photon was
emitted. Well, in familiar physics we may also say that in the
usual three-space there is quantum activity at each point. This,
at least for me, makes the terms a little more meaningful.