Re: Quantum Gravity Hypothesis

From: Ken S. Tucker (dynamics_at_vianet.on.ca)
Date: 11/25/04 

Date: 25 Nov 2004 00:20:02 -0800

analog57@yahoo.com (Russell E. Rierson) wrote in message news:<c410ffa5.0411242001.1c5656a1@posting.google.com>...
> dynamics@vianet.on.ca (Ken S. Tucker) wrote in message news:<2202379a.0411232316.2a36fac2@posting.google.com>...
> > analog57@yahoo.com (Russell E. Rierson) wrote in message news:<c410ffa5.0411231956.40a52120@posting.google.com>...
...
Russell, I think you did good post.

> > > A metric field can be defined by the primary substratum of events.
> > > Thus the intrinsic geometrical structure of spacetime is predicated on
> > > the pseudo-Riemannian spaces via the affine relationships ? all
> > > physical events are fully reducible to manifestations of the
> > > substratum i. e. the event density generating a metric field.
> >
> > I think the wording is sloppy. An event is a point
> > in 4 coordinates x,y,z,t. The term "event density"
> > *might* refer to spacetime field density, but do I
> > have to guess?
>
> The book "Gravitation" - by Misner, Thorne, and Wheeler[1st chapter],
> says that points in spacetime are characterized by "what happens
> there". Give a point in spacetime the name "event". World lines of
> particles form a criss-crossing very analogous to coordinates.
> Worldlines fill up spacetime. Events relate to other events.

Yes, the universe has many photons following worldlines
for reference, but when you actually measure one, by
aborption or emission, Heisenburg makes us limit our
accuracy to dx,dy,dz,dt,de, which I term an occurance.
  In basic relativity we *simplify* the occurance to be
an event at x,y,z,t, but then we leave the real world
of measurement and go into an imaginary world of continuous
manifolds independent of energy and matter, that is
inconsistent with GR and QT.
  
> > > The overlap of events as ripples- being the wave functions - circular
> > > conic 2D cross sections, generates new "smaller" ripples that are
> > > contained in the outer "past" ripples-cross sections,
> >
> > These so-called ripples imply an "occurance".
> > An occurance is much more complex than an event.
> > An occurance needs dx,dy,dz,dt,de (e=energy) at
> > some fuzzy location x,y,z,t.
> > The "de", usually a photon, proves the existance
> > of matter, which in turn, from the PoV of GR tells
> > spacetime where it is. Hence we survey spacetime
> > using photons, as a result of the occurances.
 
> Yes, an event is a "happening" or an occurance.
>
> http://dictionary.reference.com/search?q=event&r=67
>
> QUOTE:
>
> event
>
> Something that takes place; an occurrence.
>
> A significant occurrence or happening. See Synonyms at occurrence.
>
> A social gathering or activity.
>
> The final result; the outcome.
>
> Sports. A contest or an item in a sports program.
>
> Physics. A phenomenon or occurrence located at a single point in
> space-time, regarded as the fundamental observational entity in
> relativity theory.

Close but if you want to invite Webster to lecture on
physics, well you know what I mean,
 
> END OF QUOTE
>
> > Bilge and I had a discussion about this before,
> > and Bilge pointed out that we should not screw
> > with the definition of what an event is, leave
> > it as x,y,z,t and I agree.
>
> Tensors are coordinate independent. In the real world,
> events[occurances] relate to other events[occurances]. The real world
> doesn't require a superimposing of Cartesian, or other coordinates, on
> it.

Basically that's true. But a tensor must be able to
be specialized as a set of measurements wrt some
arbituary CS. So somewhere in the process one will
need to be *able* to define an event at x,y,z,t, by
an occurance, dx...de, at the point of measurement.
 
> > >thus the
> > > locality principle is not violated and describes non-paradoxically,
> > > what appears as non-local transfer of information.
> > >
> > > [event_2^0_[[[_[_[event 2^n_]___]_]]]]]
> > >
> > > Intersections[the overlapping] of event boundaries
> >
> > You see, the term "event boundaries" is poor
> > vocabulary, (hey I used it and was rightly corrected),
> > and should be termed "occurance" boundaries,
> > because dx,dy,dz,dt,de is fuzzy.
>
> The terms "Event" and "occurance" are interchangable for this purpose.

I'm not sure. It's my impression Smolin is presenting
an analogy for a description of quantizing GR, not an
easy thing to do, understandably. But I object to
*bastardizing* (no offense intended), the definition
of event.

His "ripples" in spacetime are better descibed as the
result of occurances because they involve energy.
 
> > Occurances continually over-lap.
> >
> > >also provides a
> > > better definition for "bits" of physical information, where the
> > > information density of the universe is continually increasing.
> >
> > A non-zero divergence of information. No wonder
> > the universe will always be smarter than us!
> >
> > > Time is defined as an iterative sequence of outer[past] events
> > > including all inner[future] events.
> >
> > I think the ISU has defined "physical" time very
> > well, if one intends to introduce new definitions
> > of time, they must be able to transform that definition
> > to the ISU standard or justify a change in that standard.
>
> The above definition doesn't contradict the ISU standards.

OK, but it seems like a complicated way to describe a Cesium
clock, unless he has something different in mind.
 
> > Did Lee Smolin really say this in all seriousness?
> > Ken S. Tucker
>
> Yes.
>
> http://books.guardian.co.uk/reviews/scienceandnature/0%2C6121%2C438833%2C00.html
>
> QUOTE
>
> But in Einstein's theory, space is something else altogether. It
> arises out of the relationships between objects - planets, galaxies
> and so on. Think of a sentence, says Smolin; it is not simply a
> container into which one puts words. Without any words, there would be
> no sentence; similarly, in Einstein's theory, space has no existence
> apart from the objects that move within it.
>
> END OF QUOTE

Thanks for the ref's.
Regards
Ken S. Tucker