# Re: What We Can Know About the World

[RS]
On 7/31/05, Russell Standish <[EMAIL PROTECTED]> wrote:
> On Sat, Jul 30, 2005 at 12:25:48PM -0700, Lee Corbin wrote:
> >
> > This is not to say that progress is impossible. Consider an idea
> > like Aditya has:  what is the real difference between an event
> > and an observer-moment?  In trying to answer that question, many
> > of us may learn something (at least for our own purposes).
> >
>
> Err, 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
> corresponds the the "state" vector \psi of quantum mechanics.
>
> Perhaps you have different definitions of these terms, but it seems
> like chalk and cheese to me.
> 

Lets not constrain an "event" to mean something only in 4-space. Take
any N-Space and you can define it in terms of a set of N-dim. events.
Ofcourse I agree with your definition, am just making it scale over
dimensions.

Now consider an "observer moment" to be exactly what you are defining
it to be: information KNOWN about the world at a moment of time. The
"coming to know" of any information corresponds to an "event". Thus an
"observer moment" is well-defined if and only if "event" is defined.
In other words, an Observer-Moment exists iff it's corresponding
"coming to know" event exists for "some" observer. In terms of light
cones, OMs are the Events at and "after" the crossing over of light
cones.

I think the distinction is not a qualitative one between the two, only
those events which interfere with the set of events "observable" by
"us" (who are also just sets of events) correspond to
"observer-moments" in "our universe". So the set of OMs is simply a
subset of the set of all events.

refer to my previous mail about the multiverse as a partition with
equivalence classes which are maximal sets of connected "observer
moments", in other words, maximal sets of "mutually interfering
events". visualize this as connected components of a graph.

Defining entities in more than one different sets of words does not
rule out their qualitative identity. Every Observer-Moment is an
event. Every event is an Observer-Moment in some universe.

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