Re: SR consistency is crap.
From: J.E. (troubled6man_at_yahoo.com)
Date: 11/25/04
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Date: 24 Nov 2004 21:19:23 -0800
"robert j. kolker" <nowhere@nowhere.net> wrote in message news:<30hqjsF2u641cU1@uni-berlin.de>...
> J.E. wrote:
>
> > I will only discuss the invariant theory, go here, jump coordinates
> > here, and "look Newton's law is the same", that's unnecisarily
> > complicated AND it makes people with Newtonian bagagge bring it into
> > SR. Just use proper time. Just use proper length. Drop all
> > discussion of frames, it isn't necissary and it causes confusion to
> > some people, so do it invariantly. Once I see the letter "t" I know
> > that it's a different theory than the one I use, because I don't use
> > coodinates.
>
> Suppose you need corroberation from another person and to get it you had
> to tell him to look for an event of some sort. How do you specify the
> event (which consists of WHERE and WHEN) without specifying a fiducial
> frame of reference which you both share.
You could describe a series of events and what would happen next. You
could even say that the series of events are laying a meter-stick
end-to-end 500 times and then waiting until the watch he wears goes
off. His "watch" could tick uninformly and the meter stick could have
a battery that heats it up causing it to expand, the point is that if
you take those things into account, then it doesn't matter that the
watch and meter stick aren't a suitable to define an actual frame.
> How do you tell the post office where to deliver your mail without
> giving an address (which is a set of co-ordinates wrt to some standard
> location frame).
You describe events relative to other events. My house is between
Joe's house and Bob's house. If they know Bob's house and Joe's house
and know what a house is and there aren't other houses between them,
then that's sufficient. And these labels don't have to be a "full
frame", you only need two. Inbetweenness is a concept of all frames.
It's like doing elementary geometry, they DID somehow manage to
describe a triangle before Decartes introduced coordinates.
> Bob Kolker
I can't tell you if you are even trying to take me seriously the idea
of a postal address being a "standard frame" is frankly absurd to me.
The point is that a physical model just requires that you predict
events. The events that can be observered all on the world-lines of
future-pointing curves and you COULD inroduce a proper time relative
to that curve, but that'd be equivalent to imaging that the person has
a clock and just saying which clock-ticking EVENTS the new event
happened BETWEEN or coincident with. If you want to fix someone's
motion, then the usual easiest way is to tell them to move such that
they get spectral line A from star A and B from star B and C from star
C, and then you know that they are at rest. If you want them to move
another way you could give the A,B, and C spectras as a fucntion of
proper time. These are all observable. Length and location is not.
In the Gauge Theory of Gravity, physical observables are independant
of arbitrary local smooth minkowski rotations and displacements. Your
location in space doesn't matter, your redshifts do.
- Next message: Patrick Powers: "Re: Wind energy a boon for farmers - tenfold returns !"
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