sci.physics.research

robert bristow-johnson wrote:

> On Sep 1, 8:33 am, Mal wrote:
> > On 11 Aug, 03:25, Zurab Silagadze wrote:
> >
> > > "Relativity without tears" can be found here
> > > /abs/
> > > I'll appreciate corrections of English. Other comments are also
> > > welcomed.
> >
> > You say:
> >
> > Because for Newtonian intuition "to take as a postulate that the speed
> > of light is constant relative to changes in reference frame is to
> > assume an apparent absurdity. It goes against common sense. No wonder,
> > thinks a student, that we can derive other absurdities, such as time
> > dilation and length contraction, from the premises"[5].
> >
> > But is this really so absurd? It may go against common sense
> > initially, but surely it can be accepted with little pain? The rocket
> > ship goes faster, time dilates. Where's the problem in accepting that?
> > It's just a fact like any other. Accepting quantum mechanical
> > paradoxes is much more of a problem.
>
> i think that for Einstein, it there was no non-absurd option other
> than the speed of the same bean of light had to be constant relative
> to different inertial observers.
>
> given the axiom that the laws of physics are the same for every
> inertial observer (and why shouldn't they be?), then it is that
> Maxwell's equations are those laws of physics that, if identical in
> every respect for any and every inertial observer, is the principle
> from where you deduce that the speed of light in vacuo is the same for
> every observer.

You are going round in circles.

> so you have this changing E field that is causing this changing B
> field that is causing this changing E field that is causing this
> changing B field that is causing this changing E field that is causing
> this changing B field and all that changing E and B field is, by
> solving Maxwell's equations, propagating at this speed, c = 1/
> sqrt(eps0*mu0), would not two inertial observers, both moving relative
> to the other and both observing the same little beam of light (doesn't
> matter which of them might be holding the flashlight), measure that
> speed to be the same for each observer? they have the same eps0 and
> mu0, don't they? why should one observer be preferred over the other
> (which is what would have to be the case if one measured c to be
> different than the other) so that this one observer has the more
> "correct" value for c?

There is no reason at all why the laws of physics
have to be the same for every observer.
We have found this to be the case,
but we can imagine other universes
where such would not be the case.

Other possibility:
The privileged observer is the one for whom Maxwell's eqns
hold in their simplest form.
For all others there are extra terms,
related to their motion.
In fact, untill Einstein showed otherwise
everyone believed this to be the case.

Compare for example with Newtonian mechanics under rotation.
There is one priv-ed observer (the non-rotating one)
for whom the planets move under Newtons laws in their simplest form.
For all other observers there are extra terms.
(Coriolis and centrifugal)

There can be no 'logical' or 'natural' reason
why our universe can't be like this
with respect to Maxwell's eqns,
only an empirical one.
And that only within experimental limits
on preferred frame effect.

Best,

Jan