Re: relativity of simultaneity - real or perceived?

On 22 May 2005 02:45:05 -0700, "Curious" <anthonyroseuk-curious@xxxxxxxxxxx>
wrote:

> Martin, thanks for your surprising patience and efforts, but
> I honestly believe I've absorbed all this stuff correctly now.
> I've realised how it works: the Lorentz transformations simply
> predict how things would look from another inertial frame, by
> working 'backwards' from experimental results,

Absolutely correct. But, reason WHY it's the Lorentz transform
and not, for example, the Galilean Transform, has everything to
do with the physical nature of the medium and its manifestation
in material systems.

> and happily alter time as well as distance in order to arrive at
> the right answer.

Altering time was an arbitrary choice, one predicated on
Einstein's second postulate, namely' the speed of light will
always be defined to have the same value' in any inertial
frame

This in conjunction with the fundamental 'fact' that light
speed IS fixed and a function of the medium, independent of
all motion of emitters and receivers within it, requires us
to use certain conventions. For example, lets use a simple
sonic system and define the one unit of time of a sonic clock
to be the time it takes for a sound pulse to travel from
emission to reception. i.e., emission is tick and reception
is tock, the configuration is as follows:

B
___ (Reflector)
^
|
|
d (Distance, fixed)
|
|
|
_
/ \ (Transmitter/receiver)
A

So, the 'delta' time (t') to go 2d is simply

t' = 2d/c
and is, by our definition, is one unit of time for our system
of measure. Also, since we've DEFINED our unit of time in
terms of c (wave speed), we can also define distance as what
can tbe 'measured' by ranging, D = ct. Given that t is BASED
on 2d/c, in our case, D = 2d, as expected...

___ (Reflector)
^
/|\
/ | \
/ d (Distance, fixed)
d' | d'(actual traveled distance)
/ | \
/ | \
_ _
/ \ / \ (Transmitter/receiver)


Given that we've defined tick-tock as the time it takes a pulse
of sound to make the round trip from A to B back to A it is quite
obvious that in this case,

t' = t/gamma

Where gamma = Sqrt(1 - [v/c]^2)

which is a simple result of the trigonometry of the ray-paths...

We however will find that

2d'/t' = 2d/t

for all cases of v < c. So, this means that for our simple
sound clock, in this configuration, we cannot determine any
change of v in any inertial state, c can remain consistently
one defined value. Now, if we rotate our clock 90° so that
the pulse moves along the axis of travel AND (here's the ONLY
difference) d remains unchanged for the perpendicular case,
then

t' = t/gamma^2

Not

t' = t/gamma

And 2d/t no longer equals 2d'/t' by a factor of gamma. This
of course, was the result expected by Michelson et al.

If d shortens by exactly Sqrt(1 - [v/c]^2) again we get back
to.

2d'/t' = 2d/t

and we cannot effectively detect any changes in speed c.
Further, if all physical processes are limited to propagating
effects & information at c which is independent OF motion then,
all interacting fields, in equilbrium, to remain so must alter
their configurations to adapt to any net motion. Since matter
is an independent 'ponderable' substance but is known now to
complex QM wave structures held together by coulombic fields it
should be of no suprise that its structure is naturally altered
by a Lorentz contraction.

However, as can be seen by the logical progression above the
entire definition is inherently circular, a self-fullfilling
prophecy that WILL match any observation as long as physical
distances are contracted by gamma (Sqrt[1 - (v/c)^2]) EVEN IN
mundane sonic systems.

If you're interested in seeing the acoustic analog of QM wave
contraction due to motion through a medium let me know, I can
e-mail a OCR'd copy of a standard reference.

Paul Stowe
.

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