Re: What should a theory give us?

On Jun 6, 4:05 pm, "Jeckyl" <n...@xxxxxxxxxxx> wrote:
"harry" <harald.vanlintelButNotT...@xxxxxxx> wrote in message

news:1181134873_1813@xxxxxxxxxxxxxxxxxxx

Hmm... I already explained why it is erroneous to use the word "crush"...

I don't see that it is. They are phsycially shortened in length .. it snot
just an apparent shortening due ot how it is measured .. it is actually
physically shorter .. if something is physically make shorter so it fits in
a smaller space, then it is crushed. That LET (or at least O'Barr's version
of it) doesn't really offer any explanation of how or why that happens ..
except that it is somehow the ether doing it, and this ether applyies some
sort of crushing and slowing 'froce' onto matter that happens to correspond
with lorentz transforms and it applies to all matter and all types of
clocks.

I did explain the difference between crushing and shrinking, and any
phycisist understands that.
However, I probably did not tell you that length contraction follows
from the Maxwell equations, although Maxwell had not realised that
himself. It was first proposed by Fitzgerald based on a paper by
Heaviside. Heaviside showed in 1888 for static fields that they shrink
by a factor gamma in the direction of motion, which made it plausible
that it should be the same for intermolecular fields.

And it sounds as if you are still a bit confused about clock sync.

No. I was only confused by O'Barrs explanation of what he says happens

I can see that the slowing of the clocks would mean that if they are
synchronised in the FoR and then moved apart, the difference in absolute
speed required to do that would result in the clocks going out-of-sync
(wrt the ether frame) .. so the absolute-velocity-related slowing would
have a side-effect of getting the clocks out of sync.

So for my example of three identical objects (when at rest) each moving
at different velocities (0, v, 2v), even though they are all then
actually different absolute lengths as a result of their absolute motiob,
the object moving at speed v will see the other large and small objects
as both being the same size (but shorter by gamma factor)

Congratulations! You now DO understand it. :-)

Yes



It appear the with SR proper length is maintained and space and time
appear different when views from other FoR .. but you see the correct
proper length for the FoR where an object is stationary. Whereas in LET
(at least O'Barr's version), objects actually physicaly shrink when
moving relative to the absolute ether, but it only appears to be the
correct length for the FoR where it is at rest, and it appears to have
other lengths from other frames, and we cannot tell which is the absolute
frame.

It seem the main difference is SR keeps proper length and LET has
physical lengths changed (wrt an ether).

The only difference is that "LET" provides a physical model for SRT.
Minkowski spacetime was meant as another physical model for SRT
(according to that, "time" and "space" can be transformed into each other
by a rotation).
Of course, the use of different models leads to different ways of
expressing the same laws.

Yes .. and that in one (SR) there is no physical crushing and slowing, only
the 'illusion' of it in frames of reference other than the one in which the
object is at rest .. and in the other (LET) there is physical crushing /
slowing in an unknown absolute ether frame, and only the 'illusion' of
things not being crushed / slowed in the FoR in which the object is at rest.
As far as other FoR go, both LET and SR have the 'illusion' of different
lengths and clock rates (ie we measure things differently) .. its only in
the supposed ether frame and the object rest frame that SR and LET have
quite different explanations.

I share the opinion of Lorentz and Einstein for whom SRT is a
principle theory: on purpose there's no explanatory metaphysics
inside. Of course, everyone still plugs his/her own philosophy in, in
order to make sense of it. :-)

Cheers,
Harald

.

Relevant Pages

  • Re: "length contraction" according to Lorentz and Poincare - An example
    ... A correct ether theory would say that both A's ruler and B's ruler will ... The laws of physics based on a clock second and light path ... The laws of physics based on a defined absolute second ... length of a measuring rod is maximum in the rest frame of the aether. ...
    (sci.physics.relativity)
  • Re: Lorentz vs. Einstein
    ... >> measure of length of the same stick can vary from frame to frame, ... >> any more than the measure of masses of the sticks is absolute. ... >> It is possible via arbitrary synchronization procedures to set the pole ... .5C versus the ether. ...
    (sci.physics.relativity)
  • Re: The reasons why SR is an aether theory
    ... The speed of light is a constant math ratio of absolute space and time as ... Einstein's objection to LET was the existence of the absolute rest frame ... 1/ Maxwell's Ether theory showed that light is a wave travelling in the ... at two different speeds to go to A and B respectively through the same ...
    (sci.physics.relativity)
  • Re: What should a theory give us?
    ... physically shorter .. ... except that it is somehow the ether doing it, ... (wrt the ether frame) ... actually different absolute lengths as a result of their absolute motiob, ...
    (sci.physics.relativity)
  • Re: On the physicality of length contraction
    ... The source of this controversy is that peopole are in the habit of ... thinking of velocity as absolute. ... shorter with respect to frame X. ...
    (sci.physics.relativity)