Re: Scientifically valid definitions.

From: Patrick Reany (reany_at_asu.edu)
Date: 10/30/04 

Date: 30 Oct 2004 09:38:11 -0700

"AllYou!" <idaman@conversent.net> wrote in message news:<JMSdnVAeGcDj1BzcRVn-ig@conversent.net>...
> "Patrick Reany" <reany@asu.edu> wrote in message
> news:844a1b64.0410281114.28a4e34c@posting.google.com...
> > "AllYou!" <idaman@conversent.net> wrote in message
> news:<wsKdnYHJhPM0nRzcRVn-pg@conversent.net>...
> > > "Patrick Reany" <reany@asu.edu> wrote in message
[snip]
> > > > If you want to declare what time, or anything else "really" is, go to
> > > > metaphysics. In physics, time is what an ideal clock declares it to
> > > > be. There is no other way to view it without a circularity involved.
> > > > Just stop thinking in a metaphysical mode and you'll finally get it.
> > >
> > > I'm not. I'm claiming that time is the quatification of motion.
> > >
> > > > Physics is NOT interested in what time "really" is. Physics is NOT to
> > > > tell us what reality is, but, rather, it is merely to find a minimal
> > > > set of equations that completely describes the behavior of the visible
> > > > realm, using any models or concepts that work.
> > >
> > > Then terms like *visible realm* don't apply. What's the visible realm?
> Do
> > > you mean observable? Are you claiming that time is observable?
> >
> > A given theory tells us what is observable. Rocks, planets, frisbees
> > are visible (by convention). We need a physics by which we can predict
> > what they do (i.e., their behavior). A physics that describes what
> > light does is nice too. Long ago and far away somebody discovered that
> > one way to describe the behavior of rocks and planets, and frisbees is
> > to associate events with the position of hands on a clock. Well, over
> > the years, the look of clocks has changed, but by George, this idea of
> > timing events (associating events with clock readings) is still useful
> > to describe behavior. Get it yet? Time, in physics, is an abstract
> > variable. Clocks are observable.
>
> I get it just fine. If you go back through all of my posts here, you'll see
> that I've only been saying the same thing. All I've ever claimed is that
> time is just the quantification of motion.

Maybe it is, maybe it isn't.

> In fact, I gave a pretty
> detailed narrative that all we do when we use time is to pick a standard
> motion in the universe (e.g., the rotation of the Earth using the Sun as a
> marker) as a reference by which the position of all other particles in the
> universe are referenced. IOW, we use that steady motion as an ruler, and
> index, in the margin of the scroll of history. We record the position of
> all other particles in the universe which are of interest to us and chart
> their position relative to the position of the Earth so that we're able to
> know what the position of each particle was relative to all others at any
> given point in their paths.

See my thought experiment below.

>
> Isn't that consistent with what you're saying? Pretty damn close it seems
> to me. But then I went on to say that if time is just that quantification
> of motion, then it much be the other two properties of motion which are
> fundamental. Speed and distance are fundamental. What's more, I went on to
> say that claiming that time dilates is imprecise and an unnecessary step.
> To say that time dilates is to imply a significance about time which it does
> not have. And so does claiming that time, like other properties of nature,
> cannot be defined except in terms of that which measures it. The concept of
> time is just not that intrinsically significant. Time is easily defined as
> the quantification of motion. It's the ratio of distance to speed. What's
> so difficult about that? Distance is what a ruler measures, speed is what a
> speedometer measures, and we simply derive time from those two.
>
> So there it is. So now you tell me why it was necessary for the three
> stooges here to vilify me for this. Certainly, because I'm uneducated
> (which I've admitted all along), I'm sure my misuse of certain terms and
> conventions of science were annoying. But the vitriol and aggressive
> flaming that's going on is ridiculous. It's laughable that people of
> science would behave thus.
>
> Anyway, please excuse the rant. Just venting.

There's alot of impatient, egomaniacal, and self-righteous posters on
newsgroups. There's nothing that can be done about it.

Now, I admit that I can't think of an example of a real *** that
cannot be explained in terms of some kind of motion, but I still
maintain that:

1) the clock is still the IRREDUCIBLE standard of measuring time
2) it is conceivable that one find a clock that has no explaination in
kinematical terms.
3) Every theory has something irreducible in it. And in most (if not
all) theories in physics, time is one of those irreducibles.

1) To explain the behavior of clock A, say, in mechanical terms,
requires one to have another clock B to do the analysis. But now, to
explain B we need another clock C, etc. The process is an infinite
regress. Do you really have an infinite amount of time jst to explain
clocks?

2) Suppose I find a black box that emits a light pulse every five
seconds in its rest frame. Suppose further that no human being can
break the box to find out how it works. Still, the light pulse is
emitted like, well, like clockwork. Therefore, I am free to use the
box as an actual clock. The nature of what causes the periodicity is
irrelevant to the use of the box as a clock! Although my thought
experiment is counterfactual, it still makes a valid point countering
your obsession for defining time as peridocities of motion.

Patrick