Re: LET

From: RP (no_mail_no_spam_at_yahoo.com)
Date: 01/20/05 

Date: Wed, 19 Jan 2005 21:47:04 -0600

Tom Roberts wrote:
> RP wrote:
>
>> Tom, your arguments are wholly incorrect. In LET, wrt a frame K' in
>> motion away from the origin of the master frame K, a clock that makes
>> a trip from K' to K and back again to K' will have ticked *more* than
>> the clock that remained stationary in K'.
>
>
> Then what you mean by "LET" is not what everybody else around here means
> by that acronym. Or at least those of us who can actually read Lorentz's
> works.
>
> For the past decade or so around here LET has meant the "Lorentz Ether
> Theory", a theory based on the writings of Lorentz. The essence of LET
> comes from Lorentz's 1904 paper "Electromagnetic Phenomena in a System
> Moving with any Velocity Less than that of Light" and from his 1915
> monograph _Theory_of_Electrons_ (note that what he meant by "electrons"
> is not what we mean today).
>
> [Lorentz made an error in his definition of \rho, which
> is ignored; Poincare' showed how to define it correctly.]
>
> In those works Lorentz derived the equations of electrodynamics in a
> moving frame by asuming:
> 1. a "fixed system of coordinates" in which the ether is at rest.
> 2. a Galilean transform to the moving frame followed by a "further
> change of variables" -- when composed these are merely the
> Lorentz transform.
>
> The result is a theory of electrodynamics in a moving frame that is
> experimentally indistinguishable from SR. It is also mathematically
> equivalent to SR in that any theorem of either is a theorem of both.
>
>
> In particular, your claim above about the elapsed time of a clock is
> incorrect (though I admit to being puzzled by a "trip" from one frame to
> another -- I presume you mean from one location in K' to another and
> back again). Probably you have GUESSED what LET would predict, without
> actually computing it. Do the computation correctly and you will find
> your error.
>
>
>> LET is not SR, sorry, you've not checked this for youself,
>
>
> Yes, LET is not SR. But it si experimentally indistinguishable from SR.
> I have checked this for myself. See above. See the trilogy of posts to
> this newsgroup that includes a discussion of this:
> http://groups.google.com/groups?selm=3838AC00.87B78404%40lucent.com&output=gplain
>
> http://groups.google.com/groups?selm=3838A838.81CE8090%40lucent.com&output=gplain
>
> http://groups.google.com/groups?selm=3838AA2A.829F46AD%40lucent.com&output=gplain
>
>
>
>> Lorentz contracted the rulers only, Einstein contracted the space in
>> which the rulers were located.
>
>
> Yes. Lorentz also dilated the clocks (not "time"). Still, LET is
> experimentally indistinguishable from SR. In essence this is because we
> can measure spatial distances only using rulers, and time intervals only
> using clocks. This is a theoretical distinction without an observable
> difference.
>
>
> Tom Roberts

I understand your arguments in those posts to state that ether
theories can be viable, i.e. experimentally indistinguishable from SR,
while differing in the transform that they use. If however the
transform used is the Lorentz transform, then the theory is SR. No
other postulates can be used to derive the lorentz transform *unless*
they are consistent with the postulates of SR, since the postulates of
SR can be derived directly from the transform. I'll clarify the
necessity of this truth with the following arguments.

If I interpret the transform to mean something like: Pixies bunch up
the molecules of a moving mass, and do it according to the equation
1/sqrt(1 - (v/c)2), then I can account for the MMX null results. Then,
however, I do a little math and discover that in order to remain
mathematically consistent my clocks must vary in ticking rate, well
then Tom, this is no longer my pixie theory, this is pure applied
math. I have introduced symmetry as a postulate, since it was symmetry
that I relied upon in deriving the mathematical system used to in turn
to find what must be required by my initial "mathematical" premise.

Thus it is required that my pixies adhere to principles of symmetry,
in particular all of the laws of mathematics, in their doings, that
is, when they are bunching up those molecules it isn't a random process.

If by similar arguments, I can, by reductio, limit the behaviors of
these pixies to such an infinite extent that they require the lorentz
transform, then once having the transform I can send those pixies
packing since it has become obvious that they have no power to do
anything; it is the math and the symmetry that requires the molecules
to bunch together as they do.

In the OP's paper, he begins exactly as did Lorentz, by postulating
variations in interatomic forces with changes in motion wrt the master
frame (ether). Now I'll make it as clear to you as I possibly can that
if this postulate has any more merit than the pixie postulate above,
then it must follow that two masses that are separated in free space,
and comoving, will be bound by exactly the same sort of forces,
independently of the separation of those masses, since their spacing
must change wrt me whenever they are equally accelerated wrt the
master frame that I've arbitrarily decided that I'm located in.

This is because as the case may be, there is a solid uninterrupted rod
laid alongside these masses, of length equal to the spacing of these
physically separate objects. Lorentz can account for the change in
separation of the masses as nothing other than the contraction of the
space between them, that is, since they are not bound to each other in
their relative position, this being an empirical matter and not
observed. Once having made the required addition to the theory that
the space between the separated masses reduces in the absence of
interatomic forces acting between these masses, then it follows that
it is simply the space itself that is reduced in measure, and thus the
space underlying the rod must equally contract.

It follows that this is the real reason for the contraction of the
rod, i.e. that the space between the molecules has changed. This
discovery negates his original premise, as in directly contradicting
it. As you can see, Lorentz' premise is fully equivalent to pixies,
having no prescriptive potential whatsoever, and turns out to be
incorrect in that it is wholly redundant. Though it may be accepted
that the premises of LET lead to the lorentz transform, it should be
noted that if you accept LET as a theory because of its mathematical
equivalence to SR, then you are logically constrained by this
statement to include a new class of theories summed up as follows: Any
and all possible interpretations of the lorentz transformation
equations, including those invoking pixies, hobgoblins, and even god.

SR correctly frames no hypothesis, i.e. it doesn't address the
question of "why". It is derived by mathematical argumentation alone,
using as premises empirically derived equations, Maxwell, MMX, etc.,
and repeatability (symmetry), and perhaps an unexpressed intuitive
understanding of those shortcomings of the Lorentz interpretation that
I outlined above.

PS, I don't remember ever finding the lorentz transform in Lorentz's
writings, but if you intend to hold that he derived them, then who am
I to argue, you're the expert. Perhaps you can provide the location of
  that derivation for us.

Richard Perry

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