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From: Tom Roberts on 27 Jun 2010 12:36
Mitchell Jones wrote:
> ***{Time is that which is measured by a standard clock and by every
> other clock which has been designed to match the readings of a standard
> clock. The acceptance of this definition is, for example, why a clock
> intended to be used in a GPS satellite is designed to lose 38
> microseconds per day when at sea level: the goal is that it match the
> readings of a standard clock on the ground, while it is in orbit. Since
> it will speed up by 38 microseconds per day when placed in orbit, it has
> to lose 38 microseconds per day while on the ground.

Some of this is correct. But note that to an observer on a GPS satellite, the
satellite's clock does not measure standard time; nor does a ground clock. You
are implicitly assuming that earth is a VERY special place, in that only clocks
on its surface correctly display "time" -- that's an OUTRAGEOUSLY parochial view.


> The implication: time advances at the same rate throughout the universe,
> by definition.

You will find it impossible to follow through on that notion. In particular,
there is no global notion of "time" in GR. All one can find is the proper times
of individual objects, observers, and trajectories, or time coordinates of
various coordinate charts. NONE of those can be extended to the "entire
universe" [*]. NONE of those has any justification to claim to be "universal
time" -- each is valid only LOCALLY.

[*] Except in exceptionally simple manifolds that cannot possibly
model the world we inhabit.

Your notion of a "universal time" is also in conflict with an important
observation about the world we inhabit: all physics is local. A "universal time"
would be irrelevant -- physical phenomena would progress according to their
usual rates in local conditions, ignoring any sort of "universal time".


> Absolute time--time that advances at the same rate throughout the
> universe--is the only concept of time that works in the real world.

Not true. It may work in YOUR everyday life, and your rather simplistic notions
of how that extends to the rest of the universe, but it does not work in GR. But
then, GR has no need for any such global notions, because all physics is local.


> If
> the relativists don't like that, let 'em howl.

It's not just "relativists" that "don't like" your attempt to do science by
assertion, it is every scientist who ever lived. You must develop a theory, not
just make disconnected statements about how you THINK the world works, or about
how you HOPE it does. And you must then TEST that theory. Such armchair
theorizing worked for Aristotle; nobody accepts it today....


> The reality is that their
> precious GPS would not work, if clocks in the GPS satellites were not
> designed to advance at the same rate as standard clocks on the ground.

This is true (once stated properly, which you did not). Of course that's why the
GPS was designed as it was, with rate offsets in the satellite clocks. But there
is no notion of "absolute time" here, it's just that the GPS approach is the
simplest and most straightforward way to construct locally-Minkowski coordinates
in a region near earth, using atomic clocks both on the ground and in
satellites. It is not the only way....


> Result: they are hoist by their own petard.

No. The problems and inconsistencies are all yours.


Tom Roberts
From: Tom Roberts on 27 Jun 2010 14:46
Robert L. Oldershaw wrote:
> (1) The value of the gravitational coupling factor G' has never been
> measured within an Atomic Scale system [atom, ion or particle].

Yes. There are several efforts to do this, including both hydrogen atoms and
anti-hydrogen atoms. I participated in a Fermilab proposal to do this, but it
has not been approved, and most likely will not be.


> (2) Virtually every physicists will tell you he/she is 100% certain
> that G = 6.67 x 10^-8 cgs applies within Atomic Scale systems and
> everywhere else in the Universe.

Obviously you don't know very many physicists. I work daily with dozens of
physicists, at a lab with hundreds on staff and thousands of visitors. I do not
think that any of them would make such a statement -- "100% certain" is just not
what we would say for something like this.

Say, rather, that at present our best model of gravity is applicable at scales
from centimeters to billions of kilometers; it might be applicable at larger
scales, but the jury is still out (and will be until the puzzles of dark matter
and energy are resolved). This model is, of course, General Relativity. It
simply is not known whether it is valid at atomic scales (the issues of quantum
gravity are quite different from this), though there appears to be no reason to
expect it not to be valid there.


Tom Roberts
From: Androcles on 27 Jun 2010 15:31

"Tom Roberts" <tjroberts137(a)sbcglobal.net> wrote in message
news:huydnXJhRI3qAbrRRVn_vwA(a)giganews.com...
| Robert L. Oldershaw wrote:
| > (1) The value of the gravitational coupling factor G' has never been
| > measured within an Atomic Scale system [atom, ion or particle].
|
| Yes. There are several efforts to do this, including both hydrogen atoms
and
| anti-hydrogen atoms. I participated in a Fermilab proposal to do this, but
it
| has not been approved, and most likely will not be.
|
|
| > (2) Virtually every physicists will tell you he/she is 100% certain
| > that G = 6.67 x 10^-8 cgs applies within Atomic Scale systems and
| > everywhere else in the Universe.
|
| Obviously you don't know very many physicists. I work daily

Bwahahahahahahahaha!
Roberts has delusions of employment!
You haven't worked since Lucent Technologies fired you out for
wasting company time on usenet, Roberts. Oops! Sorry... retired you.



From: waldofj on 27 Jun 2010 15:33
On Jun 27, 2:46 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote:
> Robert L. Oldershaw wrote:
> > (1) The value of the gravitational coupling factor G' has never been
> > measured within an Atomic Scale system [atom, ion or particle].
>
> Yes. There are several efforts to do this, including both hydrogen atoms and
> anti-hydrogen atoms. I participated in a Fermilab proposal to do this, but it
> has not been approved, and most likely will not be.

That's a real shame. I think this is a very important line of
research. Over the decades I have read many "discussions" about things
like: quantum gravity, just what is anti-matter, better tests of the
equivalence principle, and so on. This line of research would go a
long way in reducing the "noise factor"
From: Mitchell Jones on 27 Jun 2010 17:08
In article <S5qdnSfVcpv_7LrR4p2dnAA(a)giganews.com>,
Tom Roberts <tjroberts137(a)sbcglobal.net> wrote:

> Mitchell Jones wrote:
> > In article <Ou2dnSrelu1cer_RRVn_vwA(a)giganews.com>,
> > Tom Roberts <tjroberts137(a)sbcglobal.net> wrote:
> >> Robert L. Oldershaw wrote:
> >>> Can you specify any physical system undergoing any specific physical
> >>> interaction that violates causality.
> >> I'm not sure what "violates causality" means.
> >
> > ***{The notion of an uncaused event violates causality.
>
> Hmmm. that of course presupposes a useful definition of "cause". My main
> point
> is that using the NAIVE notion of causality, this is not possible. You, and
> Oldershaw, have a rather vague notion of what you mean, but have not given
> any
> specific definition. Indeed, given the long history of the subject, it is
> EXTREMELY unlikely that you, or anybody else, can do so.

***{I already did, but you snipped it out. Here it is again:

"(E)verything which happens (every effect) arises out of the interaction
of a specific set of entities, and ... the interaction in question
constitutes the cause of the effect."

When the interactions of the antecedents are understood, the cause is
understood.

As I also indicated in the material you snipped out, the linkage
between cause and effect constitutes a necessary connection across the
time sequence of events of precisely the sort that Hume, and his modern
acolytes, deny.

--Mitchell Jones)***

> > The importance of the law of causality
>
> WHAT "law of causality" ????

***{You snipped it out. Here it is again:

"(E)verything which happens (every effect) arises out of the interaction
of a specific set of entities, and ... the interaction in question
constitutes the cause of the effect."

I can't put sticky labels on everything I say so that you will recognize
what it is. Therefore let me offer you some advice: stop snipping out
virtually everything I say. If you will insert your comments into my
text, immediately after whatever sentence you are responding to, I think
you will be able to recognize what you are seeing without the need for
sticky labels.

--Mitchell Jones}***

> >> Note that classical electrodynamics does indeed have causality in the
> >> modern
> >> sense
> >
> > ***{There is nothing "modern" about equating correlation,
>
> Go back and read what I wrote. This is not at all what causality means in
> modern physical theories like classical electrodynamics. The meaning is VERY
> different from what you are trying to discuss."

***{I said that several different ways in the material which you snipped
out. For example:

"There is nothing "modern" about equating correlation, including
perfect correlation, with 'causation.' David Hume argued more than 200
years ago that perfect correlation, which he termed "constant
conjunction," was the best we could do, and that apprehension of
necessary connections within a time-sequence of events was impossible.
His conclusion was that the principle of scientific induction--that
things will behave in the future as they behaved in the past--was an
article of faith, resting on nothing, and that science, as a
consequence, rested on precisely the same grounds as religion. Your
notion of causation 'in the modern sense' is merely an admission that
the Humian point of view has prevailed, and that the term 'modern
science' has, as a result, become an oxymoron."

There was, of course, no sticky label attached to the above, saying:

"Note that the idea of causation described in this paragraph differs
markedly from the classical concept described elsewhere in this post."

And, I would add, there was also no sticky label attached to the
definition quoted earlier, which you also snipped out, saying:

"Note that this is a description of the classical concept of causality,
and that it involves presumed necessary connections across the
time-sequence of events."

I can't put sticky labels on an electronic transmission, Tom. We could,
I suppose, exchange paper messages via regular mail. That would allow me
to attach sticky labels at various points and lead you by the hand like
a child, but, frankly, I don't have time for that. If, therefore, you
want to discuss this subject, then please stop snipping out virtually
everything I say, and start inserting your comments into my text after
the sentences you are responding to.

--Mitchell Jones}***

> > ***{There is nothing "naive" about the idea that no thing may come into
> > existence out of nothing or vanish into nothing (the principle of
> > continuity),
>
> That is known as conservation of energy and momentum, not "causality". This
> is indeed not naive. But if you confuse this with "causality" the discussion
> becomes hopeless....

***{I didn't say it was "causality," I actually inserted a parenthetical
comment describing it as "the principle of continuity." In effect, there
was a sticky label present, and you simply ignored it. Here is the
entire sentence, most of which you snipped out:

"There is nothing 'naive' about the idea that no thing may come into
existence out of nothing or vanish into nothing (the principle of
continuity), and that, as a consequence, all forces are exerted by
entities in collision, and that, as a further consequence, everything
which happens (every effect) arises out of the interaction of a specific
set of entities, and that the interaction in question constitutes the
cause of the effect."

Here is the sticky label you apparently needed to comprehend the above:

"Note that the latter portion of the above sentence, starting after the
second comma from the end, is a description of the classical concept of
causality."

As for whether the discussion "becomes hopeless...," the answer would
appear to be that it was hopeless from the outset, since an exchange of
messages in which one party snips out and essentially ignores everything
the other person says can hardly be described as a "discussion."

--Mitchell Jones}***

>
> Tom Roberts

*****************************************************************
If I seem to be ignoring you, consider the possibility
that you are in my killfile. --MJ
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