Re: A new SR principle!


"Gerald L. O'Barr" <globarr@xxxxxxxxx> wrote in message
news:1175632791.639011.232260@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Subject: Re: A new SR principle!

harry <harald.vanlintelButNotT...@xxxxxxx> wrote:
Gerald L. O'Barr <globarr...@xxxxxxxxx> wrote:
. . .

<deletes by O'Barr>

O'Barr wrote:
. . . . .
Therefore, if this moving object is a
rotating object, and in its rotation it has a
radius that at one
point of the rotation lies in the direction
of motion, and in another position of its
rotation it lies perpendicular to its motion,
then parts of this rotating object would have to
be going through expansions at one point, and
going through contractions instantly thereafter,
as it rotated.

harry <harald.vanlintelButNotT...@xxxxxxx> wrote:
Sure - so far no problem. The problem starts when
you claim that such will lead to mechanical
(i)nstabilities. That it is known to be correct
*if* only length contraction would occur (as
measured in your frame). However, such is not the
case. As measured in the moving frame, the physics
will be most probably standard physics. In order to
conveniently verify that this is so (at least in
theory) you may consider to do a mapping with -for
example- a Lorentz transformation. :-)

O'Barr comments:
Just to keep the record straight, in my previous
discussions, I did not ever talk about making any
transformations between frames in any way or at any
time. I was only taking about what occurs in your
own SR frame, about objects that moved in your own SR
frame. If in your own SR frame, something happens
that fails to work, then it obviously must also fail
to work in any other SR frame.

Sure. My point is that you did *not* show that such is the case, as you made
a comparison to a fact of experience that does not apply here.

In my deleted portion, you seemed to skip over
what was said about these problems with differences
in sizes.

No, instead I commented on it - and now again here above.

These differences in sizes will cause
failure to occur in those mechanical situations where
sizes are important. I would like to have your
comments (your acceptance) of these size problems
first, before we say too much about these instability
problems.

Again, size variation only implies instability when nothing else changes
that may compensate for it. You could just as well propose a
Kennedy-Thorndike experiment here, predicting a significant fringe shift
based on the erroneous assumption that length contraction occurs without
time dilation.

Whether it is a size problem or an instability
problem, it does not matter, it will cause the
mechanical action to fail. So please, let us keep
straight all the details of the problem. Yes, the
stability concept is only a guess, but it is a good
guess.

The issue is not if, in principle, relativistic rotation speed could lead to
mechanical failure if we neglect the effect of inertial forces - for sure
everyone agrees on that. I now indicated three times that it's for sure a
bad guess that any theoretical mechanical failure must be different when the
system is in inertial motion. And below I see no serious calculation, while
that is *necessary* for such issues.
BTW, the more complex you make it, the more it will become a "David
Seppala". Of course, you could do like him and start a new thread in which
you only present a simple "SRT problem" that you "don't understand".
I don't feel like that now (and I'm running out of time), but it's quite
possible that then a few people will provide you useful answers, which will
be interesting.

Best regards,
Harald

The differences in size is not a guess, we
all can instantly observe these differences in
dimensions which will occur for many standard types
of mechanical designs.
If you are having a problem with these differences
in dimensions, let me state it again: In SR, if at
any time you have a dimensional tolerance requirement
existing in the same direction in which you have a
difference in velocity, you are going to have a
theoretical failure. Let us mention just a couple of
situations. If you have a cylinder inside of a
sleeve, the simple motion of the cylinder up and down
in the sleeve will not normally interfere with the
sleeve, since the changes in the dimensions of the
moving cylinder would be in the thickness of the
head, not in the diameter of the cylinder. And thus,
such a system would probably remain proper even under
relativistic speeds. But if the cylinder were
rotating within the sleeve, then the changes in
dimension (due to the circumference trying to shrink,
will cause a loss of tolerance, and ultimate failure
in the design.
Now the one example I gave, of the perpendicular
crossing of two sets of railroad tracks forming a
square, inclosing a tight fitting square within this
square, is absolutely valid. As these two sets of
tracks are moved at right angles to each other, the
dimensions between each pair of tracks will change by
a different ratio than the square trapped between the
tracks, and the mechanics will fail. No math is
necessary to see this. The tracks individually are
moving at V, but the square within the square is
moving at V*2^0.5. It is obvious what is happening,
and any mechanics that uses such a relationship (and
I know many locomotives use to use such relationships
in controlling the steam valves in entering and
leaving the main drive piston), will fail under
relativistic speeds.
Please tell me you understand how these
differences in sizes occur! This is just as
important as any other thought being put forth! If
you state your agreement with these size problems,
then no more really needs to be said, the contention
that there are mechanical limits to certain
mechanical motions will have been established.
Let me put off for a moment the instability
problem, for it will not occur unless we are sure
that there really are changes in sizes, etc.

Yes, SR is simple in many ways, but we all know we
all make mistakes from time to time. With me being
the least on this net, you can be sure I have made a
few mistakes. But you have not shown any mistakes
that I have made in this post.

Thanks for reading.
Gerald L. O'Barr <globarr...@xxxxxxxxx>
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