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Relativity without tears

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Zurab Silagadze

unread,
Aug 10, 2007, 10:25:06 PM8/10/07
to
"Relativity without tears" can be found here
http://uk.arxiv.org/abs/0708.0929
I'll appreciate corrections of English. Other comments are also
welcomed.

pel...@london.edu

unread,
Aug 11, 2007, 10:21:52 AM8/11/07
to
On Aug 11, 3:25 am, Zurab Silagadze <silaga...@inp.nsk.su> wrote:
> "Relativity without tears" can be found herehttp://uk.arxiv.org/abs/0708.0929

> I'll appreciate corrections of English. Other comments are also
> welcomed.

As a part-time academic editor (mainly for management science), and
with physics as a hobby (PhD in theoretical chemistry, some time ago),
I'd be happy to do the English correction if you email me for details
at pel...@london.edu

P.

Mal

unread,
Sep 1, 2007, 8:33:39 AM9/1/07
to
On 11 Aug, 03:25, Zurab Silagadze <silaga...@inp.nsk.su> wrote:
> "Relativity without tears" can be found herehttp://uk.arxiv.org/abs/0708.0929

> 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.

robert bristow-johnson

unread,
Sep 1, 2007, 3:54:06 PM9/1/07
to

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.

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?

r b-j

__________________

DRLunsford

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Sep 3, 2007, 9:50:23 PM9/3/07
to
On Aug 10, 10:25 pm, Zurab Silagadze <silaga...@inp.nsk.su> wrote:
> "Relativity without tears" can be found herehttp://uk.arxiv.org/abs/0708.0929

> I'll appreciate corrections of English. Other comments are also
> welcomed.

Simply awful. You took a perfectly easy to understand, physically
motivated theory and made into something grotesque and strange. It was
interesting to bring up projective metrics (see below), but you
totally botched that too.

Light cone: (x-t)(x+t) = 0 -> Minkowski metric (affine, not projective
geometry).
Circular points at infinity: (x+iy)(x-iy) = 0 -> Euclidean metric
(also affine).

Can *anyone* think physically these days?

-drl

J. J. Lodder

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Sep 8, 2007, 1:56:28 PM9/8/07
to
robert bristow-johnson <r...@audioimagination.com> wrote:

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

David Winsemius

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Sep 16, 2007, 1:11:31 PM9/16/07
to
Zurab Silagadze <sila...@inp.nsk.su> wrote in
news:1186757242.3...@z24g2000prh.googlegroups.com:

At the time, 1905, hadn't the constancy of the speed of light been
experimentally demonstrated? Starlight aberration? Michelson-Morley? Wasn't
it the case that the theorists were turning themselves inside out trying to
avoid the contradictions? Einstein just accepted experimental evidence.

J. J. Lodder

unread,
Sep 19, 2007, 10:56:59 PM9/19/07
to
David Winsemius <doe_...@comcast.n0T.de> wrote:

> Zurab Silagadze <sila...@inp.nsk.su> wrote in
> news:1186757242.3...@z24g2000prh.googlegroups.com:
>
> > "Relativity without tears" can be found here
> > http://uk.arxiv.org/abs/0708.0929
> > I'll appreciate corrections of English. Other comments are also
> > welcomed.
> >
>
> At the time, 1905, hadn't the constancy of the speed of light been
> experimentally demonstrated?

How could you possibly demonstrate such a thing -experimentally-?

> Starlight aberration? Michelson-Morley? Wasn't
> it the case that the theorists were turning themselves inside out trying to
> avoid the contradictions? Einstein just accepted experimental evidence.

On the contrary, he postulated the constancy of the speed of light,
and after that all the experimental evidence suddenly made sense,
(with some reinterpretation)

Jan

Message has been deleted

robert bristow-johnson

unread,
Sep 21, 2007, 11:28:25 AM9/21/07
to

i didn't think so, Jan. i start with the *axiom* that the laws of
physics are the same for every inertial observer. there is no
circular path that takes me there. it's an axiom, but one that is
more sensible and consistent than the contrary which would be (as you
describe below) the case that some inertial observers get one set of
laws of physics and some other inertial observers get some other set
of laws (even if the difference between these sets of laws are merely
different coefficients). now, conceivable the latter can sorta make
sense if the coefficients that we're referring to are the
*dimensionless* parameters like the 26 enumerated by John Baez (so one
inertial observer has an alpha of 1/137.036 while another has an alpha
of 1/137.037 and something would be measurably and operationally
different for the two inertial observers). but this doesn't make
sense for a dimensionless parameter like c since different finite
values for c, assuming all the dimensionless parameters remain
constant, would only result in a change in scaling that would be not
"operationally meaningful" as Michael Duff might call it.

> > 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.

but they would be goofy and not consistent.

> 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.

their motion relative to what? why are they moving and the
priviledged observer is not?

> In fact, untill Einstein showed otherwise
> everyone believed this to be the case.

they had to, because they couldn't or didn't comprehend that time was
not observed to be the same thing for every observer everywhere.

> 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.

right. there *is* a difference between not rotating and rotating at a
constant angular speed. there is a difference between no acceleration
and some non-zero acceleration.

> For all other observers there are extra terms.
> (Coriolis and centrifugal)

yup. those other observers are accelerated. they are not inertial.

> 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.

to me, thinking about some of the early thought experiments of the
young Einstien, it certainly does seem less logical and natural that,
in a vacuum where you cannot hook onto any tick marks or reference
points, that one inertial observer has a different experience of life
than another inertial observer. it's only because you're looking
outside the train and referencing points on the ground assumed to be
stationary, that there is any difference between you in the constant
velocity train and the guy standing outside watching the train go by.

i dunno.

r b-j

Uncle Al

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Sep 21, 2007, 3:41:11 PM9/21/07
to
Murray Arnow wrote:
[snip]

> [1] There is a slight bit of irony here. Einstein initially proposed a
> research thesis needed for graduation from ETH that was an experiment to
> measure the the speed of the earth through the aether. Weber disallowed
> the topic because it was done, unknowingly to Einstein, some 13 times
> before. Weber introduced Einstein to a paper by Wien which discussed the
> measurements.

A 2007 study sensitive to 10^(-16) relative employed two simultaneous
interferometers over a year's observation: Optical in Berlin, Germany
at 52°31'N 13°20'E and microwave in Perth, Australia at 31°53'S
115°53E. An aether background could never be at rest relative to both
of them at any moment (local background) and certainly not over a year
(galactic background).

http://arXiv.org/abs/0706.2031
Phys. Rev. Lett. 99 050401 (2007)

All spatial anisotropy measurments (Michelson-Morley experiments) and
astronomical observations (vacuum circular dichroism via rotation of
plane-polarized EM across the spectrum, from quasars and such) are
conducted with photons (massless sector). They always null.

Nobody has conducted a spatial anisotropy experiment in the massed
sector to sufficient sensitivity (~10^(-13) relative). Affine and
teleparallel gravitation theories specifically describe an anisotropic
vacuum background toward chiral mass distribution. It is the only
empirical disagreement between metric and non-metric gravitations. It
is the *only* interesting place to look.

Curiously,

http://scitation.aip.org/prl/covers/99_12.jsp
"these yield a new combined limit (blue ellipse) in good agreement
with the standard model (black star)."

Unless Uncle Al's eyes (and credulity) have gone sour, it looks like
the Standard Model prediction is slightly *outside* observation. That
is "poor agreement." There is a small chiral offset - consistent with
a very dilute anisotropic chiral vacuum background. The vacuum should
be left-handed in the massed sector and diastereotopically interact
with parity-violating experiments beyond Standard Model predictions.

--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/lajos.htm#a2

J. J. Lodder

unread,
Sep 23, 2007, 4:24:35 PM9/23/07
to
robert bristow-johnson <r...@audioimagination.com> wrote:

Your 'why shouldn't they be?' begs the question.
There is no reason at all why they should be,
except that we happen to know from experience that they are.

> > > 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.
>
> but they would be goofy and not consistent.

There is nothing goofy about preferred frame effects.
On the contrary, they can be searched for.
(with null results so far)

> > 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.
>
> their motion relative to what? why are they moving and the
> priviledged observer is not?

To the world aether of course.
Seriously though: the priviledged observer is the one
who doesn't see preferred frame effects.
For the time being we are all priv-ed
but there is (and can be) no -logical- reason
why this happy state of affairs must continue forever,
with increasing precision of the experiments.

> > In fact, untill Einstein showed otherwise
> > everyone believed this to be the case.
>
> they had to, because they couldn't or didn't comprehend that time was
> not observed to be the same thing for every observer everywhere.
>
> > 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.
>
> right. there *is* a difference between not rotating and rotating at a
> constant angular speed. there is a difference between no acceleration
> and some non-zero acceleration.
>
> > For all other observers there are extra terms.
> > (Coriolis and centrifugal)
>
> yup. those other observers are accelerated. they are not inertial.

Round in circles again.
You only know these observers are inertial
-because- they see no inertial forces.
(unless you invoke Mach's principle,
which is another postulate)

Best,

Jan

J. J. Lodder

unread,
Sep 23, 2007, 4:24:35 PM9/23/07
to
Murray Arnow <ar...@iname.com> wrote:

> J. J. Lodder wrote:
> >David Winsemius wrote:
> >
> >> Zurab Silagadze wrote in

> >>
> >> > "Relativity without tears" can be found here
> >> > http://uk.arxiv.org/abs/0708.0929
> >> > I'll appreciate corrections of English. Other comments are also
> >> > welcomed.
> >> >
> >>
> >> At the time, 1905, hadn't the constancy of the speed of light been
> >> experimentally demonstrated?
> >
> >How could you possibly demonstrate such a thing -experimentally-?
> >
> >> Starlight aberration? Michelson-Morley? Wasn't
> >> it the case that the theorists were turning themselves inside out trying to
> >> avoid the contradictions? Einstein just accepted experimental evidence.
> >
> >On the contrary, he postulated the constancy of the speed of light,
> >and after that all the experimental evidence suddenly made sense,
> >(with some reinterpretation)
> >
> >Jan
> >
>

> It also dawned on Einstein that simultaneous events aren't simultaneous to
> all observers: time was not as Newton believed it to be. That's when
> things really made sense. The constancy of the speed of light was an
> outgrowth of that. I believe that was the historical sequence.
>
> The constancy of the speed of light in a vacuum is built into Maxwell's
> Equations. That was known well known at the time; Einstein alludes to that
> in his 1905 paper.

The Maxwell equations say nothing of the kind.
They say so -only with the additional assumption-
that they hold in the same form for every (inertial) observer.

This is what nobody believed before 1905,
and what constituted Einstein's fundamental contribution.
(generalised to the relativity postulate)

Before Einstein it was believed that the Maxwell eqns
would hold in their standard form for one priviledged obverser
(the one at rest with respect to the world aether)
and that for other observers there would be corrections
to Maxwell's eqns. (to be searched for)

Null results such as Michelson's
were explained by various ad-hoc assumptions,
such as a physically real Fitzgerald-Lorentz contraction.

Best,

Jan

Message has been deleted

Tom Roberts

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Sep 24, 2007, 2:20:15 PM9/24/07
to
J. J. Lodder wrote:
> The Maxwell equations say nothing [about constancy of the speed of light].

> They say so -only with the additional assumption-
> that they hold in the same form for every (inertial) observer.
>
> This is what nobody believed before 1905,
> and what constituted Einstein's fundamental contribution.
> (generalised to the relativity postulate)

IMHO you got it backwards here. The Principle of Relativity was well
established long before Einstein (it dates back to Galileo). Einstein's
departure was to consider Maxwell's EQUATIONS to be "laws of physics" in
their own right, INDEPENDENT of the aether theory Maxwell used to derive
them. Then he applied the PoR to the equations and followed where that
led (though his exposition in his 1905 paper is somewhat different).

Today this is almost unknown and rarely (if ever) taught in physics
courses -- we call them "Maxwell's equations", and not "Maxwell's aether
theory", but that's what it was originally. Of course now we also know
several derivations of the Maxwell's equations which do not involve an
aether, so this is really an aspect of history, not physics.

The fact that Einstein's method worked is on the surface quite
remarkable (accepting equations while rejecting their derivation via
physical arguments), but with today's understanding we know that it
happened because of deeper underlying symmetries. It seems that Einstein
"lucked out" here, but I think it was rather an aspect of his particular
insight and genius. After all, SR was the first major step in the modern
era of physics and its emphasis on underlying symmetries.

> Before Einstein it was believed that the Maxwell eqns

> would hold in their standard form for one priviledged obverser [...]

Yes. Because that is now Maxwell obtained them originally.

Tom Roberts

Daryl McCullough

unread,
Sep 24, 2007, 2:20:17 PM9/24/07
to
robert bristow-johnson says...

>On Sep 8, 1:56 pm, nos...@de-ster.demon.nl (J. J. Lodder) wrote:

>> 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.
>
>but they would be goofy and not consistent.

I'm not sure whether this helps, but another way of
looking at things is in terms of what are the
fundamental scalar, vector and tensor
fields of various theories.

Galilean relativity has universal time, which means a scalar
field T(P) associated with every point P in spacetime. It also
has a 3D spatial metric tensor g_ij that applies to submanifolds
consisting of all points P with the same value of T(P).

These fields are non-dynamic. They are God-given and are not
affected by matter or forces.

If you try to include Maxwell's equations, without giving up
the universal time T, then you are forced to introduce a preferred
frame of rest. This amounts to a vector field U^u(P), which is the
4-velocity of a particle at rest in the preferred frame. Again,
this vector is non-dynamic.

Special Relativity gets rid of the nondynamic scalar field T
and also the nondynamic vector field U^u. But it keeps the
nondynamic metric tensor g_uv (extending it to cover arbitrary
vectors in spacetime).

General Relativity, in contrast, has no nondynamic scalar,
vector or tensor fields.

So the "goofy" fact about Maxwell's equations in the context
of Galilean absolute time is just that there is a mysterious
vector field U^u that determines an absolute frame of rest.
But why should a nondynamic vector field be any more mysterious
than a nondynamic scalar field (as in Galilean relativity) or
tensor field (as in Special Relativity)?

--
Daryl McCullough
Ithaca, NY

robert bristow-johnson

unread,
Sep 24, 2007, 2:20:16 PM9/24/07
to
On Sep 23, 4:24 pm, nos...@de-ster.demon.nl (J. J. Lodder) wrote:
> robert bristow-johnson <r...@audioimagination.com> wrote:
> > On Sep 8, 1:56 pm, nos...@de-ster.demon.nl (J. J. Lodder) wrote:
> > > robert bristow-johnson <r...@audioimagination.com> wrote:
..

> > > > given the axiom that the laws of physics are the same for every
> > > > inertial observer (and why shouldn't they be?),
..

>
> Your 'why shouldn't they be?' begs the question.
> There is no reason at all why they should be,
> except that we happen to know from experience that they are.
>
..

> > > 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.
>
> > but they would be goofy and not consistent.
>
> There is nothing goofy about preferred frame effects.

i think there is. besides not being inconsistent with Michaelson-
Morley, there is a preferrence of simplicity for it. i don't think
the fundamental mechanisms of interaction in Nature would bother to
take on a Rube-Goldberg description even if some current descriptions
of reality are still comparable to such. however, i think that
history is consistent with that science advances more rapidly or even
sorta revolutionary when a description of it takes on a much simpler
form and it is still widely encompassing. stuff like Maxwell's
Equations, which literally inspired Einstein - he admired and was
jealous of Maxwell for tying up all of EM in 4 pretty concise
equations. so, if there is currently an icky description of some
physical interaction, i think there is hope and even that it is the
more reasonable expection that this icky description of some
interaction is a result of our lack of depth of understanding of it
rather than that the actual physical reality really *is* this icky
relationship.

> On the contrary, they can be searched for.
> (with null results so far)

so you're expecting not-null results in the future?

> > > 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.
>
> > their motion relative to what? why are they moving and the
> > priviledged observer is not?
>
> To the world aether of course.

:-0

> Seriously though: the priviledged observer is the one
> who doesn't see preferred frame effects.
> For the time being we are all priv-ed
> but there is (and can be) no -logical- reason
> why this happy state of affairs must continue forever,

i think that science is advanced when the fundamental description of
it is understood in a manner that is "as simple as possible, but not
simpler."

> with increasing precision of the experiments.

but there are limits to that too, no? i'm not as sanguine as you that
with some finite increase in limits of some instrumentation that data
points, sufficient in number and confidence, will lie outside the
range that is predicted within the current model (say GR or for little
things, the Standard Model).

..


> > > 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.
>
> > right. there *is* a difference between not rotating and rotating at a
> > constant angular speed. there is a difference between no acceleration
> > and some non-zero acceleration.
>
> > > For all other observers there are extra terms.
> > > (Coriolis and centrifugal)
>
> > yup. those other observers are accelerated. they are not inertial.
>
> Round in circles again.

i don't know why you say so. if you're not inertial, your description
of physics (in your accelerated frame of reference) has more terms on
it. fewer terms in the inertial frame of reference. why is that
circular?

> You only know these observers are inertial
> -because- they see no inertial forces.

i don't know exactly what you're saying here, Jan. i don't think i
disagree with it, but i dunno what is salient in it that i am missing.

> (unless you invoke Mach's principle,
> which is another postulate)

isn't that also the currently-held orthodoxy?

anyway, Jan, i'm not a physicist, i'm just an electrical engineer that
does signal processing for a living - with an interest in some of this
stuff, but i still think it's not philosophically dangerous to expect
more simplicity in the description of nature as science advances.

r b-j

Martin Ouwehand

unread,
Sep 24, 2007, 5:24:04 PM9/24/07
to
Dans l'article <fd7346$hs9$1...@e250.ripco.com>,
ar...@iname.com (Murray Arnow) écrit:

] J. J. Lodder wrote:
]
] >Before Einstein it was believed that the Maxwell eqns


] >would hold in their standard form for one priviledged obverser

] >(the one at rest with respect to the world aether)


] >and that for other observers there would be corrections
] >to Maxwell's eqns. (to be searched for)

]
] I can find no reference that supports this.

see for instance pages 811-812 of Lorentz' 1904 paper, "Electromagnetic
phenomena in a system moving with any velocity smaller than that of light"
available here:

http://www.historyofscience.nl/search/detail.cfm?startrow=3&pubid=615&view=image

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|___________ Email/PGP: http://personnes.epfl.ch/martin.ouwehand ____________
The need for big brains may be what
explains the weakness of gravity [Brandon Carter]

Timo A. Nieminen

unread,
Sep 24, 2007, 5:24:04 PM9/24/07
to
On Mon, 24 Sep 2007, Murray Arnow wrote:

> J. J. Lodder wrote:


>> Murray Arnow wrote:
>>
>>> The constancy of the speed of light in a vacuum is built into Maxwell's
>>> Equations. That was known well known at the time; Einstein alludes to that
>>> in his 1905 paper.
>>
>> The Maxwell equations say nothing of the kind.
>

> Yes, they do. Perhaps stated in another way "Maxwell's equations,...,
> require that the process of the propagation of light in vacuo with the
> velocity c be independent of the frame of reference from which the process
> is observed.", Mechanics, A. Sommerfeld, p.11, Academic Press, 1952.


>
>> They say so -only with the additional assumption-
>> that they hold in the same form for every (inertial) observer.
>

> See above.

The usual 4 Maxwell field equations say nothing of the kind. Assuming that
the constitutive relations are independent of reference frame is another
story. One can say that classical electrodynamics, as understood post 1908
or so, imply special relativity. For Maxwell's electrodynamics, see below.

>> Before Einstein it was believed that the Maxwell eqns
>> would hold in their standard form for one priviledged obverser
>> (the one at rest with respect to the world aether)
>> and that for other observers there would be corrections
>> to Maxwell's eqns. (to be searched for)
>

> I can find no reference that supports this.

How about Maxwell's Treatise, with G, the velocity of a point (relative to
the ether)? Also, Maxwell's posthumously published letter in Proc. R.
Soc. 30, 108, 1880. See also Hertz's theory of electrodynamics in moving
media. Modern electrodynamics is not Maxwell's.

>> Null results such as Michelson's
>> were explained by various ad-hoc assumptions,
>> such as a physically real Fitzgerald-Lorentz contraction.
>

> True. And it was indeed Einstein's "Theory of Relativity" that put an end
> to the aether construct. Strangely, after the General Theory of
> Relativity, Einstein began thinking about the aether again.[1]

Not in England, or in France. Special relativity may well have made the
ether unnecessary, but it didn't put an end to it.

--
Timo Nieminen - Home page: http://www.physics.uq.edu.au/people/nieminen/
E-prints: http://eprint.uq.edu.au/view/person/Nieminen,_Timo_A..html
Shrine to Spirits: http://www.users.bigpond.com/timo_nieminen/spirits.html

Message has been deleted

Martin Ouwehand

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Sep 28, 2007, 6:49:59 AM9/28/07
to
Dans l'article <fdbag8$afh$1...@e250.ripco.com>,
ar...@iname.com (Murray Arnow) écrit:

] My understanding of [excerpt from Lorentz' article] is that at least
] one person was unhappy with the introduction of a privileged reference
] frames.

Lorentz, as most physicists at the time, would have been quite happy
if Michelson and Morley had found evidence of one privileged reference
frame (the Aether's). When they didn't, Lorentz had to face the situation
and try to find an explanation, and I think you should say "compeled to
abandon" instead of "unhappy with".

But I pointed to those two page because they show that it came quite
naturally to Lorentz to start his article by using different forms
of Maxwell's equations in the Aether frame and in the moving frame,
and I thought your remark "I can find no reference that supports
this" was about this.

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|___________ Email/PGP: http://personnes.epfl.ch/martin.ouwehand ____________

I don't want to seem frivolous though
obviously I'm not, because I'm a physicist [Lisa Randall]

Message has been deleted

Martin Ouwehand

unread,
Oct 4, 2007, 11:49:41 AM10/4/07
to
Dans l'article <fdj3lm$5gb$1...@e250.ripco.com>,
ar...@iname.com (Murray Arnow) écrit:

] I was addressing Jan Lodder's statement, "it was believed," that there was
] a preferred reference frame before Einstein's 1905 paper. "Belief" meaning
] to be generally accepted was the point. I haven't seen where it was
] established and accepted that there should be a preferred reference frame.

maybe it wasn't formulated like that, but it was expected/hoped that
it was possible to detect the movement of the earth with respect to
the aether. Otherwise, how do you explain that people were surprised by
the outcome of the Michelson-Morley experience ? But I agree that talking
of a "preferred reference frame" may be a modern reformulation of this
point of view.

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|___________ Email/PGP: http://personnes.epfl.ch/martin.ouwehand ____________

Quantum mechanics raises not a single fresh metaphysical problem [M. Gardner]

robert bristow-johnson

unread,
Oct 4, 2007, 4:01:19 PM10/4/07
to
On Oct 4, 11:49 am, see....@end.of.post.ch (Martin Ouwehand) wrote:
> Dans l'article <fdj3lm$5g...@e250.ripco.com>,

> ar...@iname.com (Murray Arnow) écrit:
>
> ] I was addressing Jan Lodder's statement, "it was believed," that there was
> ] a preferred reference frame before Einstein's 1905 paper. "Belief" meaning
> ] to be generally accepted was the point. I haven't seen where it was
> ] established and accepted that there should be a preferred reference frame.
>
> maybe it wasn't formulated like that, but it was expected/hoped that
> it was possible to detect the movement of the earth with respect to
> the aether. Otherwise, how do you explain that people were surprised by
> the outcome of the Michelson-Morley experience?

it depends on which "people" you are referring to. as i read the
history (i'll find the specifics, if you put me on the spot), Einstein
knew of the M-M result as was utterly unsurprised. i can't remember
the quote, but it was something like "... as if God had any choice in
the matter." (i know that Einstein was not a theist in the
traditional sense of the word, but used such language to illustrate a
point.)

if the M-M experiment was not conceived of or performed until 1904, i
think that Einstein would have confidently predicted the null
outcome. and if it had come out differently Einstein would have been
greatly disconcerted and might possibly have challenged the veracity
of the non-null result. no outcome of M-M, other than "null", ever
made any sense to Einstein.

r b-j

Christophe de Dinechin

unread,
Oct 6, 2007, 6:56:35 AM10/6/07
to
On Aug 11, 4:25 am, Zurab Silagadze <silaga...@inp.nsk.su> wrote:
> "Relativity without tears" can be found herehttp://uk.arxiv.org/abs/0708.0929

> I'll appreciate corrections of English. Other comments are also
> welcomed.

This thread prompted me to re-publish my old page on "relativity for
the 10 years old".

http://cc3d.free.fr/Relativity/Relat1.html

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