Why Einstein is the founder of special relativity

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Charles Francis

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Sep 5, 2005, 10:47:58 AM9/5/05
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I don't think this so much a matter of who found what equation, or of
what property is implied by what they said. Einstein reduced special
relativity to the empirical study of how we actually go about measuring
things. This did not require a prior knowledge of Maxwell's equations,
but an observation about how we use light in the empirical *definition*
of time and space coordinates. The MM experiment was not strictly
required, but had light not behaved in the way it does, it is not just
relativity which would be wrong, but we would have no meaningful
definition of the metre, and would not be able to state Maxwell's
equations.

Regards

--
Charles Francis

cma...@yahoo.com

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Sep 5, 2005, 2:12:40 PM9/5/05
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Charles Francis wrote:
> I don't think this so much a matter of who found what equation, or of
> what property is implied by what they said.

This is in flagrant contradiction with the title of your new thread
which indicates that you purport to show that Einstein is THE founder.

> Einstein reduced special
> relativity to the empirical study of how we actually go about measuring
> things.

As long as we know how to synchronize clocks and we have the Lorentz
transformations, we're equipped for that task. But this was established
before Einstein.

> This did not require a prior knowledge of Maxwell's equations,
> but an observation about how we use light in the empirical *definition*
> of time and space coordinates. The MM experiment was not strictly
> required,

Okay, so Einstein's SR would have been some kind of educated guess.

> but had light not behaved in the way it does, it is not just
> relativity which would be wrong, but we would have no meaningful
> definition of the metre, and would not be able to state Maxwell's
> equations.

Okay, so Einstein's SR would have been some kind of falsified educated
guess. So how does it make him THE founder? He guessed the lottery
numbers right and won the jackpot, sorry Henri no cigar. Welcome to
random science.

Chris

Charles Francis

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Sep 5, 2005, 3:30:40 PM9/5/05
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In message <1125941399.0...@f14g2000cwb.googlegroups.com>,
cma...@yahoo.com writes

>Charles Francis wrote:
>> I don't think this so much a matter of who found what equation, or of
>> what property is implied by what they said.
>
>This is in flagrant contradiction with the title of your new thread
>which indicates that you purport to show that Einstein is THE founder.

No contradiction at all. I am saying that the Einstein's theory of
relativity does not consist so much of the mathematical equations but of
the reasoning on which those equations are founded.


>
>> Einstein reduced special
>> relativity to the empirical study of how we actually go about measuring
>> things.
>
>As long as we know how to synchronize clocks and we have the Lorentz
>transformations, we're equipped for that task.

>From his logical viewpoint Einstein did not start with the Lorentz
transformations. They were established by reason from first principles.
That is the essence of the theory.


>
>> This did not require a prior knowledge of Maxwell's equations,
>> but an observation about how we use light in the empirical *definition*
>> of time and space coordinates. The MM experiment was not strictly
>> required,
>
>Okay, so Einstein's SR would have been some kind of educated guess.

Yes. That is the inspiration required of genius. But it goes deeper than
that. It is only a small step to say that relativity does not depend on
the speed of light (suppose the photon had tiny mass) but depends on the
maximum theoretical speed of information. When you make that step, no
guess is needed.
>

Regards

--
Charles Francis

cma...@yahoo.com

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Sep 5, 2005, 8:00:53 PM9/5/05
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Charles Francis wrote:
> In message <1125941399.0...@f14g2000cwb.googlegroups.com>,
> cma...@yahoo.com writes
> >Charles Francis wrote:
> >> I don't think this so much a matter of who found what equation, or of
> >> what property is implied by what they said.
> >
> >This is in flagrant contradiction with the title of your new thread
> >which indicates that you purport to show that Einstein is THE founder.
>
> No contradiction at all. I am saying that the Einstein's theory of
> relativity does not consist so much of the mathematical equations but of
> the reasoning on which those equations are founded.
> >
> >> Einstein reduced special
> >> relativity to the empirical study of how we actually go about measuring
> >> things.
> >
> >As long as we know how to synchronize clocks and we have the Lorentz
> >transformations, we're equipped for that task.
>
> From his logical viewpoint Einstein did not start with the Lorentz
> transformations. They were established by reason from first principles.
> That is the essence of the theory.

If Poincare didn't establish them by reason from first principles, then
according to your criterion below, that makes him an even greater
genius than Einstein. I'm not trying to claim that, but I couldn't
resist pointing out an absurdity.

All that's required is that the Lorentz transformations constitute the
unique solution that satisfies all constraints. And Poincare solved
that problem. The rest is just didactical stuff for human consumption.
It only gives people the illusion they grasp something about it.

> >> This did not require a prior knowledge of Maxwell's equations,
> >> but an observation about how we use light in the empirical *definition*
> >> of time and space coordinates. The MM experiment was not strictly
> >> required,
> >
> >Okay, so Einstein's SR would have been some kind of educated guess.
>
> Yes. That is the inspiration required of genius.

Amusing... we know that he knew about Michelson-Morley.

Chris

Charles Francis

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Sep 6, 2005, 10:59:16 AM9/6/05
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In message <1125963893....@g49g2000cwa.googlegroups.com>,

cma...@yahoo.com writes
>Charles Francis wrote:
>> In message <1125941399.0...@f14g2000cwb.googlegroups.com>,
>> cma...@yahoo.com writes
>> >Charles Francis wrote:
>> >> I don't think this so much a matter of who found what equation, or of
>> >> what property is implied by what they said.
>> >
>> >This is in flagrant contradiction with the title of your new thread
>> >which indicates that you purport to show that Einstein is THE founder.
>>
>> No contradiction at all. I am saying that the Einstein's theory of
>> relativity does not consist so much of the mathematical equations but of
>> the reasoning on which those equations are founded.
>> >
>> >> Einstein reduced special
>> >> relativity to the empirical study of how we actually go about measuring
>> >> things.
>> >
>> >As long as we know how to synchronize clocks and we have the Lorentz
>> >transformations, we're equipped for that task.
>>
>> From his logical viewpoint Einstein did not start with the Lorentz
>> transformations. They were established by reason from first principles.
>> That is the essence of the theory.
>
>If Poincare didn't establish them by reason from first principles, then
>according to your criterion below, that makes him an even greater
>genius than Einstein. I'm not trying to claim that, but I couldn't
>resist pointing out an absurdity.

Poincare is acknowledged as one of the greatest mathematicians in
history and was a great genius. I don't know precisely where he would be
ranked, but possibly top ten, almost certainly top twenty; definitely a
greater mathematician than Einstein.

>All that's required is that the Lorentz transformations constitute the
>unique solution that satisfies all constraints. And Poincare solved
>that problem. The rest is just didactical stuff for human consumption.
>It only gives people the illusion they grasp something about it.

No. That entirely misses the point of sr. It is understandable given the
way sr is often taught, as though the whole content is contained in the
Lorentz transform. The essential feature of Einstein's theory of
relativity is that it is logically based on the special principle of
relativity.


>
>> >> This did not require a prior knowledge of Maxwell's equations,
>> >> but an observation about how we use light in the empirical *definition*
>> >> of time and space coordinates. The MM experiment was not strictly
>> >> required,
>> >
>> >Okay, so Einstein's SR would have been some kind of educated guess.
>>
>> Yes. That is the inspiration required of genius.
>
>Amusing... we know that he knew about Michelson-Morley.
>

I'm sure he also knew that Maxwell's equations predict the constancy of
the speed of light, and I doubt he expected MM to falsify that.

Regards

--
Charles Francis

thomas_l...@hotmail.com

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Sep 6, 2005, 10:59:17 AM9/6/05
to
Carlo Rovelli discusses the topic in this thread on page 2 of
http://www.arxiv.org/abs/quant-ph/9609002 . This paper is quite
interesting in other respects, too.

Harry

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Sep 6, 2005, 10:59:17 AM9/6/05
to

"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
news:mNz1YzQK...@clef.demon.co.uk...

>
> I don't think this so much a matter of who found what equation, or of
> what property is implied by what they said. Einstein reduced special
> relativity to the empirical study of how we actually go about measuring
> things.

Hmm.. your above statement that "Einstein reduced special relativity" does
not match with your claim that "Einstein is the founder of special
relativity".

If you meant that Einstein founded the modern way of presenting SRT, I think
that most people will agree.

> This did not require a prior knowledge of Maxwell's equations,
> but an observation about how we use light in the empirical *definition*
> of time and space coordinates.

> The MM experiment was not strictly
> required, but had light not behaved in the way it does, it is not just
> relativity which would be wrong, but we would have no meaningful
> definition of the metre,

At that time there was a very meaningful definition of the metre, and we
could have kept it.

> and would not be able to state Maxwell's equations.

I wonder...

Harald


Charles Francis

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Sep 6, 2005, 3:55:00 PM9/6/05
to
In message <431d58e8$1...@epflnews.epfl.ch>, Harry
<harald.v...@epfl.ch> writes

>
>"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
>news:mNz1YzQK...@clef.demon.co.uk...
>>
>> I don't think this so much a matter of who found what equation, or of
>> what property is implied by what they said. Einstein reduced special
>> relativity to the empirical study of how we actually go about measuring
>> things.
>
>Hmm.. your above statement that "Einstein reduced special relativity" does
>not match with your claim that "Einstein is the founder of special
>relativity".
>
>If you meant that Einstein founded the modern way of presenting SRT, I think
>that most people will agree.

You miss my point. The important thing about the special theory of
relativity is not the mathematical equations which are produced, but the
logical order in which they are produced, and from what assumptions.

>
>> This did not require a prior knowledge of Maxwell's equations,
>> but an observation about how we use light in the empirical *definition*
>> of time and space coordinates.
>
>> The MM experiment was not strictly
>> required, but had light not behaved in the way it does, it is not just
>> relativity which would be wrong, but we would have no meaningful
>> definition of the metre,
>
>At that time there was a very meaningful definition of the metre, and we
>could have kept it.

Actually it is not hard to show the equivalence of the definitions, once
you accept the definition of synchronicity.


>
>> and would not be able to state Maxwell's equations.
>
>I wonder...
>

If the photon had a small mass the theory of relativity would still
hold, but c would be a limiting speed, the maximum speed of
information. In this case a modified form of Maxwell's equations could
hold. But if there were no such thing as c, and there was no bound on
the speed of information, then everything would be quite different.

Regards

--
Charles Francis

Perspicacious

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Sep 7, 2005, 2:27:41 AM9/7/05
to
In a culture that believes that Einstein discovered
relativity out of his own unimaginable genius and
fertile imagination, a more relevant question would
be, "What were the contributions to relativity before
and after Einstein?" Was Einstein's idea outrageously
new and original or did he merely take the next logical
baby step beyond previously existing ideas?

http://eprint.uq.edu.au/archive/00002307/01/larmor.pdf
http://philsci-archive.pitt.edu/archive/00000987/00/Michelson.pdf
http://www-cosmosaf.iap.fr/Poincare-RR3A.htm
http://arxiv.org/abs/physics/0408077
http://www.everythingimportant.org/viewtopic.php?t=1094
http://www.everythingimportant.org/viewtopic.php?t=1100


Admral

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Sep 7, 2005, 2:29:36 AM9/7/05
to
Charles Francis wrote:
[...]

> Poincare is acknowledged as one of the greatest mathematicians in
> history and was a great genius. I don't know precisely where he would
> be ranked, but possibly top ten, almost certainly top twenty;
> definitely a greater mathematician than Einstein.

A poll among mathematicians would most probably rank him top five.
Personally, I think he is second after Euler.

Charles Francis

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Sep 7, 2005, 3:11:13 PM9/7/05
to
In message <1125991826....@z14g2000cwz.googlegroups.com>,
thomas_l...@hotmail.com writes

>Carlo Rovelli discusses the topic in this thread on page 2 of
>http://www.arxiv.org/abs/quant-ph/9609002 . This paper is quite
>interesting in other respects, too.
>
Yes. If any one is in any doubt that Einstein is rightly considered the
founder of sr, they should look at what Rovelli says.


Regards

--
Charles Francis

Charles Francis

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Sep 7, 2005, 3:11:13 PM9/7/05
to
In message <1125937378.8...@g14g2000cwa.googlegroups.com>,
Perspicacious <iperspi...@yahoo.com> writes

>In a culture that believes that Einstein discovered
>relativity out of his own unimaginable genius and
>fertile imagination, a more relevant question would
>be, "What were the contributions to relativity before
>and after Einstein?" Was Einstein's idea outrageously
>new and original or did he merely take the next logical
>baby step beyond previously existing ideas?

In my view, very definitely the next logical baby step. But make no
mistake, determining what the next logical baby step is, amid the
confusion of idiots saying different things, and making it, and
explaining it to others, this is the work of genius.

Regards

--
Charles Francis

Harry

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Sep 7, 2005, 7:28:42 PM9/7/05
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"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
news:YWnClXLD...@clef.demon.co.uk...

> In message <431d58e8$1...@epflnews.epfl.ch>, Harry
> <harald.v...@epfl.ch> writes
> >
> >"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
> >news:mNz1YzQK...@clef.demon.co.uk...
> >>
> >> I don't think this so much a matter of who found what equation, or of
> >> what property is implied by what they said. Einstein reduced special
> >> relativity to the empirical study of how we actually go about measuring
> >> things.
> >
> >Hmm.. your above statement that "Einstein reduced special relativity"
does
> >not match with your claim that "Einstein is the founder of special
> >relativity".
> >
> >If you meant that Einstein founded the modern way of presenting SRT, I
think
> >that most people will agree.
>
> You miss my point. The important thing about the special theory of
> relativity is not the mathematical equations which are produced, but the
> logical order in which they are produced, and from what assumptions.

I did get your point, but you missed mine. I'll put it differently:
According to many, modern textbooks present Newton's mechanics better than
he did himself as they reduced it to a description of observables only - he
definitely used different assumptions. Following your reasoning, not Newton
but some other (textbook?) author was the founder of classical mechanics...

> >> This did not require a prior knowledge of Maxwell's equations,
> >> but an observation about how we use light in the empirical *definition*
> >> of time and space coordinates.
> >
> >> The MM experiment was not strictly
> >> required, but had light not behaved in the way it does, it is not just
> >> relativity which would be wrong, but we would have no meaningful
> >> definition of the metre,
> >
> >At that time there was a very meaningful definition of the metre, and we
> >could have kept it.
>
> Actually it is not hard to show the equivalence of the definitions, once
> you accept the definition of synchronicity.

That equivalence is related to the way light behaves. Without that
equivalence we'd still have a standard metre...
Maybe you meant that if one or a few laws of nature would be different, then
our world would be different in often unexpected ways. Sure.

> >> and would not be able to state Maxwell's equations.
> >
> >I wonder...
> >
>
> If the photon had a small mass the theory of relativity would still
> hold, but c would be a limiting speed, the maximum speed of
> information. In this case a modified form of Maxwell's equations could
> hold. But if there were no such thing as c, and there was no bound on
> the speed of information, then everything would be quite different.

I know of a lot of alternative theories, but infinite light speed was out of
the picture by then.

Cheers,
Harald

Harry

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Sep 7, 2005, 7:28:52 PM9/7/05
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"Charles Francis" <cha...@clef.demon.co.uk> wrote in message
news:ReEIs6rR...@clef.demon.co.uk...
> In message <1125963893....@g49g2000cwa.googlegroups.com>,
SNIP

> >All that's required is that the Lorentz transformations constitute the
> >unique solution that satisfies all constraints. And Poincare solved
> >that problem. The rest is just didactical stuff for human consumption.
> >It only gives people the illusion they grasp something about it.
>
> No. That entirely misses the point of sr. It is understandable given the
> way sr is often taught, as though the whole content is contained in the
> Lorentz transform. The essential feature of Einstein's theory of
> relativity is that it is logically based on the special principle of
> relativity.

First of all, I disagree with the idea of a single founder of SRT. And
indeed, the Lorentz transforms were not the cause but the solution. The
main constraint for Poincare was the Principle of Relativity that he
cherished - which Einstein next also called "principle of relativity"
but later "special principle of relativity". According to Poincare, the
new mechanics should be in accordance. Lorentz worked in that direction,
but he didn't notice yet that his theory accomplished that goal. But if
one could identify a single point in time that SRT was borne, for me it
was the day when Poincare announced at a conference that finally a
theory had been found that was PoR-compatible.

Harald

Javier Bezos

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Sep 7, 2005, 7:29:08 PM9/7/05
to

Yes, and I would lament the attempts to "divinize" Poincaré could
damage, as a reaction, his reputation (more or less as with
Einstein).

It would be unfair to think Poincaré was a mediocre physicist,
too. The way he actually applied and gave form to the PoR for all
physical phenomena advanced by Maxwell in 1877, how he reviewed
and analyzed the existing theories of the electron (by then a
fashionable topic with lots of papers) in the light of his PoR
and how he realized an error in all these theories which led him
to introduce the electron stress in the 1906 paper (even if in
contradiction with the statement in the same paper that all mass
had electromagnetical origin), reveal that he had a very good
understanding of physical phenomena.

The fact he was unable to give the step Einstein did only reveals
Poincaré was human and therefore he wasn't perfect--and saying
Eintein gave only a "baby step" won't help Poincaré either, as
this would imply Poincaré was short-minded, something I strongly
disagree.

Javier
-----------------------------
http://www.texytipografia.com

jacque...@neuf.fr

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Sep 7, 2005, 7:33:22 PM9/7/05
to
Charles Francis wrote

"If the photon had a small mass the theory of relativity would still
hold, but c would be a limiting speed, the maximum speed of
information. In this case a modified form of Maxwell's equations could
hold. But if there were no such thing as c, and there was no bound on
the speed of information, then everything would be quite different."
+++
What you are saying is fully compliant with the demo of the existence
of an invariant ( acting as maximum relative speed ) as consequence of
the PoR alone, as described in :

http://www-cosmosaf.iap.fr/Poincare-RR3A.htm#demo

Annex 1 of :

http://www-cosmosaf.iap.fr/Poincare-RR3A.htm

Whether we set this invariant equal to "c" we get the SR, but according
to the demo, it is not mandatory.

We would have other physical theories compliant with PoR with other
values of this invariant ( but I am not sure they would be formaly
different , this invariant beeing the maximum speed, it will play the
part of the speed of light in SR).
Just to notice that, in such a theory, the light would not play the
very special part it does in SR. It would be the physical phenomenon
associated to this "invariant maximum speed" which would play the part.
Just call it "light" and the game is over....

"This just remember me the stoty of the guy who tried to demonstrate
that the Illiad and Odyssey had not been written by Homer but by a guy
who had the same name..".

Note: The purpose of the memo, I wrote about the contribution of
Poincare to SR ( referenced above) , following a "wild" discussion we
had at the SAF, was not to claim that Poincare is the "inventor" of the
SR.

It is just to emphasize how, in a very different way of Einstein, he
tried to find a solution to the crisis of the physics, raised by the MM
experience, especially before and up to the the publication of the
Einstein paper in 1905 ( the details are in the memo).

This is not very well known.
We thought that it was worth to do something for reabilitating the role
of Poincare in this affair, so the memo ( we tried to be fair, and to
rely on facts).
Jacques
+++

Homo Lykos

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Sep 7, 2005, 9:42:05 PM9/7/05
to
"Harry" <harald.v...@epfl.ch> schrieb im Newsbeitrag
news:431d58e8$1...@epflnews.epfl.ch...

>
> "Charles Francis" <cha...@clef.demon.co.uk> wrote in message
> news:mNz1YzQK...@clef.demon.co.uk...
>>
>
> If you meant that Einstein founded the modern way of presenting SRT, I
> think that most people will agree.

What most people believe is no proof.

>
>> This did not require a prior knowledge of Maxwell's equations,
>> but an observation about how we use light in the empirical *definition*
>> of time and space coordinates.
>
>> The MM experiment was not strictly
>> required, but had light not behaved in the way it does, it is not just
>> relativity which would be wrong, but we would have no meaningful
>> definition of the metre,
>
> At that time there was a very meaningful definition of the metre, and we
> could have kept it.
>
>> and would not be able to state Maxwell's equations.
>
> I wonder...

I wonder too and I think that almost nobody knows Poincaré:

To the definition of time and metre Poincaré has written 1905 (view my short
notes about history of SR in http://www.soso.ch/wissen/hist/SRT/srt.htm page
498 in [P3]):

" Comment faisons nous nos mesures? En transportant, les uns sur les autres,
des objets regardés comme des solides invariables, répondrat-on d'abord;
mais cela n'est plus vrai dans la théorie actuelle, si l'on admet la
contraction lorentzienne. Dans cette théorie, deux longueurs égales, ce sont
par définition, deux longueurs que la lumière met le même temps à
parcourir."

And consequently - Poincaré has known, that this only makes sense, if c is
the limiting velocity - he was the first physicist, who was setting c = 1,
as you can see in [P2] (5/11 june 1905) and [P3] (23 july 1905/2 march
1906). This was before Einstein had finished his SR-paper. In [3] Poincaré
also realized that the special Lorentztransformation ist a rotation in the
poincaré/minkowski-spacetime. I think it should be clear from this, that
Poincaré 1905 was very modern. And don't forget: All more philosphical ideas
about space and time came from Poincaré and NOT from Einstein.

But Poincaré was 1905 not sure, if this definition (measuring of lenghts
with "light-time") would be the best definition for all times; Also today
I'm not sure too.

A hint to Poincarés "Lorentz-pressure": It is of course not a pressure
relative to an absolute system (Einsteins Ruhesystem), because such a system
physically ist not prefered in the Lorentztheory and about this point
Poincaré let no doubt in his publications since about 1900; B of a moving
charge also disappears in the "Ruhesystem".


Homo Lykos


Perspicacious

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Sep 8, 2005, 1:36:52 PM9/8/05
to

Carlo Rovelli wrote:
http://www.arxiv.org/PS_cache/quant-ph/pdf/9609/9609002.pdf

"The formal content of special relativity, however,
is coded into the Lorentz transformations, written by
Lorentz, not by Einstein, and before 1905. So, what
was Einstein's contribution? It was to understand
the physical meaning of the Lorentz transformations.
(And more, but this is what is of interest here). We
could say -admittedly in a provocative manner- that
Einstein's contribution to special relativity has been
the interpretation of the theory, not its formalism:
the formalism already existed." p. 2.

Does this mean Max Born deserves full credit for all
of quantum theory because he was the first to interpret
the square of a wave-function as being a probability
density?

Juan R.

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Sep 8, 2005, 1:36:54 PM9/8/05
to
Charles Francis ha escrito:

Precisely Rovelli is supporting modern historical view of Poincaré
priority.

Rovelly states

"Einstein's 1905 paper suddenly clarified the matter by pointing out
the reason for the unease in taking Lorentz transformations
'seriously': the implicit use of a concept (observer-independent time)
inappropriate to describe reality when velocities are high.
Equivalently: a common deep assumption about reality (simultaneity is
observer-independent) which is physically untenable. The unease with
the Lorentz transformations derived from a conceptual scheme in which
an incorrect notion -absolute simultaneity- was assumed, yielding
any sort of paradoxical consequences. Once this notion was removed the
physical interpretation of the Lorentz transformations stood clear, and
special relativity is now considered rather uncontroversial."

Precisely, the abandon of the absolute time and interpretation of LT in
a new mechanical framework with c limiting speed (therefore
relativistic effects observable to high velocities) and t relative was
achieved by Poincaré. It was Poincaré who first introduce the
spacetime (x, ct) concept before Minkoswki did.

I already cited to Poincaré assuring that there is no absolute time.
Now i will cite to Lorentz (1914):

"I had not thought of the straight path leading to them, since I
considered
there was an essential difference between the reference systems x, y,
z, t and x', y', z', t'. In one of them were used - such was my
reasoning - coordinate
axes with a definite position in ether and what could be termed true
time; in the other, on the contrary, one simply dealt with subsidiary
quantities introduced with the aid of a mathematical trick. Thus, for
instance, the variable t' could not be called time in the same sense as
the variable t. Given such reasoning, I did not think of describing
phenomena in the reference
system x', y', z', t' in precisely the same way, as in the reference
system x, y, z, t"

and adds

"I later saw from the article by Poincaré that, if I had acted in a
more systematic manner, I could have achieved an even more significant
simplification. Having not noticed this, I was not able to achieve
total invariance of the equations; my formulae remained cluttered up
with excess terms, that should have vanished. These terms were
too small to influence phenomena noticeably, and by this fact I could
explain their independence of the Earth's motion, revealed by
observations, but I did
not establish the relativity principle as a rigorous and universal
truth. On the contrary, Poincaré achieved total invariance of the
equations of electrodynamics and formulated the relativity postulate
- a term first
introduced by him"

"I am unable to present here all the beautiful results obtained by
Poincaré. Nevertheless let me stress some of them. First, he did not
restrict himself by demonstration that the relativistic transformations
left the form of electromagnetic equations unchangeable. He explained
this success of transformations by the opportunity to present these
equations as a consequence
of the least action principle and by the fact that the fundamental
equation expressing this principle and the operations used in
derivation of the field equations are identical in systems x, y, z, t
and x', y', z', t'."

Poincaré showed that equations were identical in both frames and
formulated the 4D spacetime concept with the invariant ds. For
Poincaré, Lorentz local time was not a mathematical trick, WAS the
"time read from the clocks" [Poincaré (1900) "The theory of Lorentz
and the principle of equal action and reaction"].

Also the Einstein operational definition of time being the reading of a
clock is another of Poincaré achievements.

I do not know basic principle, formalism, postulate, law, concept, or
simlar of SR that was formulated by Einstein like NEW.

"The relativity theory of Poincaré and Lorentz"
Whittaker.


See
http://canonicalscience.blogspot.com/2005/08/what-is-history-of-relativity-theory.html

for further references and data. New extended version in preparation.

Juan R.

Center for CANONICAL |SCIENCE)


Javier Bezos

unread,
Sep 10, 2005, 9:44:26 AM9/10/05
to
Harry:

> I did get your point, but you missed mine. I'll put it differently:
> According to many, modern textbooks present Newton's mechanics better than
> he did himself as they reduced it to a description of observables only - he
> definitely used different assumptions. Following your reasoning, not Newton
> but some other (textbook?) author was the founder of classical mechanics...

The famous three laws were introduced by Newton in his
Principia, but his explanation was essentially geometric
(difficult to follow today and almost even in his own time).
Lagrange and Euler developed new formalisms preserving
the laws and their physical content--the assumptions are
physically the same but not mathematically. This illustrates
the fact a formula and its physical meaning are quite
different things (note I'm saying "meaning" and not
"interpretation").

And Newton was a wise man as he only described reality
without trying to *interpret* it in terms of known
phenomena (in his Principia; Optiks is another matter).
Remember: "Hypothesis non fingo", a maxim which shouldn't
be forgotten.

Javier
-----------------------------
http://www.texytipografia.com

Homo Lykos

unread,
Sep 10, 2005, 10:57:06 AM9/10/05
to
"Javier Bezos" <see_belo...@yahoo.es> schrieb im Newsbeitrag
news:1126082874.8...@g49g2000cwa.googlegroups.com...


> The way he actually applied and gave form to the PoR for all
> physical phenomena advanced by Maxwell in 1877, how he reviewed
> and analyzed the existing theories of the electron (by then a
> fashionable topic with lots of papers) in the light of his PoR
> and how he realized an error in all these theories which led him
> to introduce the electron stress in the 1906 paper

This paper is from 23 july 1905 (appearing at 2 march 1906) and *all*
important final results of this paper you find in his note of 5/11 june 1905
in the Comptes rendus! This note may have been helpful for Einstein to
finish his own SR-paper in a shorter time.


> (even if in
> contradiction with the statement in the same paper that all mass
> had electromagnetical origin),

This is *no* contradiction, because Poincaré and nobody else could know at
that time if there exist non electromagnetic masses or not; but Lorentz and
Poincaré could make some statements about these masses, if PoR is valid.
About this point Poincaré is also speaking in [P3]
(http://www.soso.ch/wissen/hist/SRT/srt.htm).


> reveal that he had a very good
> understanding of physical phenomena.
>
> The fact he was unable to give the step Einstein did

What step, who was not known before?

Some of the most important original papers on the way to SR with short
comments in german you find in http://www.soso.ch/wissen/hist/SRT/srt.htm


Homo Lykos

Javier Bezos

unread,
Sep 11, 2005, 4:32:49 AM9/11/05
to
Homo Lykos wrote:

> This paper is from 23 july 1905 (appearing at 2 march 1906) and *all*

A universal practice in the academic world (in fact, we can
remove "academic") is to refer to papers by their publication
date. Poincaré published three papers with the same title
in 1905, 1906 and 1908, iirc.

> This is *no* contradiction, because Poincaré and nobody else could know at
> that time if there exist non electromagnetic masses or not; but Lorentz and

Read chap. 28 of Feynman's Lectures on Physics to understand
why there is a contradiction. This is a well know fact and it
has been pointed out by several physicist and researchers.

> What step, who was not known before?

For example, that electromagnetical mass and mechanical mass
were unnecessary concepts in this context. Given the huge amount
of literature assuming there were two masses with different
transformation rules, including Poincaré's papers as you just
said, Einstein's step was a bold step and closed definitely
the issue. That opened a new world of discoverings in the
few next years (for that, see for example the very well
documented Pauli's Theory of Relativity).

Javier
-----------------------------
http://www.texytipografia.com

Harry

unread,
Sep 12, 2005, 10:48:33 PM9/12/05
to

"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1126367457.7...@g14g2000cwa.googlegroups.com...
> Homo Lykos wrote:
SNIP

> Given the huge amount
> of literature assuming there were two masses with different
> transformation rules, including Poincaré's papers as you just
> said, Einstein's step was a bold step and closed definitely
> the issue.

Einstein 1905:
"[...] effects on electric or magnetic masses respectively [...]
We remark that these results as to the mass are also valid for ponderable
material points, because a ponderable material point can be made into an
electron (in our sense of the word) by the addition of an electric charge,
no matter how small. "

IMO, his argumentation there was utter nonsense.
In contrast, Lorentz 1904:

"Consequently, the proper relation between the forces and the
accelerations will exist in the two cases, if we suppose that the masses
of all particles are influenced by a translation to the same degree as
the electromagnetic masses of the electrons."

Now that I consider a bold step.

> That opened a new world of discoverings in the
> few next years (for that, see for example the very well
> documented Pauli's Theory of Relativity).

Harald


Martin Ouwehand

unread,
Sep 12, 2005, 10:48:35 PM9/12/05
to
In article <1126187763.9...@g44g2000cwa.googlegroups.com>,
"Juan R." <juanrgo...@canonicalscience.com> writes:

] Now i will cite to Lorentz (1914):


]
] "I had not thought of the straight path leading to them, since I
] considered there was an essential difference between the reference
] systems x, y, z, t and x', y', z', t'. In one of them were used -
] such was my reasoning - coordinate axes with a definite position
] in ether and what could be termed true time; in the other, on the
] contrary, one simply dealt with subsidiary quantities introduced
] with the aid of a mathematical trick. Thus, for instance, the variable
] t' could not be called time in the same sense as the variable t.
] Given such reasoning, I did not think of describing phenomena in
] the reference system x', y', z', t' in precisely the same way, as
] in the reference system x, y, z, t"

I would be grateful if you could give the full reference to this citation,
which I find very interesting because it clearly shows that for Lorentz
himself the transformation bearing his name was *not* relating space-time
measurements of the same event in different inertial frames -- it is a
"mathematical trick" concerning the "subsidiary quantities" x', t'.

Although some people apparently think otherwise, I find it fairly obvious
from reading Lorentz' 1904 article (which the above excerpt seems to be
commenting), that he believes in galilean relativity plus FitzGerald-Lorentz
contraction. I think Poincaré did too: for instance in his 1909 Conference
he explains that a ligth wavefront, spherical in one frame, would *appear*
ellipsoidal in another fame moving with respect to first, because of the
contraction of the measuring rods -- and this is definitely different from
Einstein's prediction that the wavefront would appear spherical in all
inertial frames.

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|_____________ Email/PGP: http://slwww.epfl.ch/info/Martin.html _____________
L'aide d'un parfait guru et l'aide d'une personne pleine de bonnes
intentions paraissent semblables mais gardez-vous de les confondre [Milarepa]

Homo Lykos

unread,
Sep 12, 2005, 10:48:35 PM9/12/05
to
"Javier Bezos" <see_belo...@yahoo.es> schrieb im Newsbeitrag
news:1126367457.7...@g14g2000cwa.googlegroups.com...

> Homo Lykos wrote:
>
>> This paper is from 23 july 1905 (appearing at 2 march 1906) and *all*
>
> A universal practice in the academic world (in fact, we can
> remove "academic") is to refer to papers by their publication
> date.

Not when from this a wrong impression follows. In this context follows the
absolutely wrong impression Poincarés papers to SR would follow the paper of
Einstein.

> Poincaré published three papers with the same title
> in 1905, 1906 and 1908, iirc.

This is not correct so:

1. Exactly the same title have only the papers of 5. june 1905 and of 23
july 1905

2. The paper of 5 june 1905 is only a relatively long "abstract" of the
SR-paper of 23 july 1905 with *all* most important results of the 23
july-paper for priority reasons - as I think - because Poincaré has known of
course that up to the appearance of the mainpaper in the rendiconti one had
to wait a long time. It seems that Poincaré has written his short note to
C.R. after finishing all calculations (otherwise he would not have been
able to list the correct results including the most important errors of
Lorentz) - but before he had written the full text of his july-paper in a
printable version.

>
>> This is *no* contradiction, because Poincaré and nobody else could know
>> at that time if there exist non electromagnetic masses or not; but
>> Lorentz and
>
> Read chap. 28 of Feynman's Lectures on Physics to understand
> why there is a contradiction.

It's very new to me that Feynman is expert in history. After all I know,
he himself never said this. In contrast I remember that somewhere he
explicitely claimed, that he knows history of science not by original
papers.

>
>> What step, who was not known before?
>
> For example, that electromagnetical mass and mechanical mass
> were unnecessary concepts in this context. Given the huge amount
> of literature assuming there were two masses with different
> transformation rules, including Poincaré's papers as you just
> said,

Nonsense:

Poincaré and Lorentz NOT assumed different transformation rules for
electromagnetic and mechanical masses: They claimed that all masses (forces)
have to behave in the same manner; Poincaré especially emphasized that this
has to be so if PoR is valid and such sentences you don't find for the first
time 1905, but you can find similar statements of Poincaré already in 1904,
before he had read the article of Lorentz.

> Einstein's step was a bold step and closed definitely the issue.

Nonsense again: I cite the only sentence in this context I found now in the
SR-paper of Einstein of 30 june 1905:

" Wir bemerken, daß diese Resultate über die [longitudinale und
transversale] Masse auch für die ponderablen materiellen Punkte gilt
[gelten]; denn ein Punkt kann durch Zufügen einer beliebig kleinen
elektrischen Ladung zu einem Elektron (in unserem Sinne) gemacht werden. "
(view [E1], page 919 in http://www.soso.ch/wissen/hist/SRT/srt.htm)

For me a very dark explanation, *extremely* far from a bold step.

On the other hand: For me this is one of the sentences in Einsteins paper,
which seem me to show that Einstein probably has known - before finsishing
his paper - the articles of Poincaré (and Lorentz), where he could find all
most important results of his own paper. But didactically and in writing
style it remains a master work.


Homo Lykos


Harry

unread,
Sep 13, 2005, 2:18:32 AM9/13/05
to
"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1126339829.9...@g14g2000cwa.googlegroups.com...

> Harry:
>
> > I did get your point, but you missed mine. I'll put it differently:
> > According to many, modern textbooks present Newton's mechanics better
than
> > he did himself as they reduced it to a description of observables only -
he
> > definitely used different assumptions. Following your reasoning, not
Newton
> > but some other (textbook?) author was the founder of classical
mechanics...
>
> The famous three laws were introduced by Newton in his
> Principia, but his explanation was essentially geometric
> (difficult to follow today and almost even in his own time).

Reading the introduction to the Principia was a revelation for me: his
explanation was based on the rejection of causal relative motion (of
Descartes) while modern textbooks base themselves on Newton's laws of
relative motion as if that were causal.
The two concepts are fully incompatible.
Following the reasoning of the above posting, the person who removed
Newton's absolute space concept should be called the founder of classical
mechanics, but I don't even know who it was! (Who was it?)
BTW I could follow the explanation of Newton while the textbooks that I know
don't really explain Newton's laws - instead they explain how to work with
them.

> Lagrange and Euler developed new formalisms preserving
> the laws and their physical content--the assumptions are
> physically the same but not mathematically. This illustrates
> the fact a formula and its physical meaning are quite
> different things (note I'm saying "meaning" and not
> "interpretation").

I don't know about that history and thus I don't know what you mean and if
it relates. The disagreement between Lorentz and Einstein as well as between
Newton and I-don't-know-who illustrates the fact that a formula and its
metaphysical interpretation are quite different things.

> And Newton was a wise man as he only described reality
> without trying to *interpret* it in terms of known
> phenomena (in his Principia; Optiks is another matter).
> Remember: "Hypothesis non fingo", a maxim which shouldn't
> be forgotten.

His insistence on distinguishing between appearences and inferred hidden
reality has been long forgotten...

Harald

Javier Bezos

unread,
Sep 13, 2005, 8:59:47 AM9/13/05
to

Harry wrote:

> Einstein 1905:
> "[...] effects on electric or magnetic masses respectively [...]

As usual partial citations. The original reads (English
translations):

"Now the principle of relativity requires that if the
Maxwell-Hertz equations for empty space hold good in system K,
they also hold good in system k; that is to say that the vectors
of the electric and the magnetic force--(Y', Y', Z') and (L', M',
N')--of the moving system k, which are defined by their
ponderomotive effects on electric or magnetic masses
respectively, satisfy the following equations:--"

By then "magnetic mass" and "electric mass" were synonymous for
"magnetic charge" and "electric charge". That can be deduced
easily from the context, as otherwise it would be nonsense, and
Poincaré himself used them with this meaning:

"From this hypothesis he deduced that, in the medium where this
energy is localized, an electromagnetic wave is propagated with a
velocity equal to the relation of the units of electric mass in
the electromagnetic and electrostatic systems."

Namely, c.

Javier
-----------------------------
http://www.texytipografia.com


Juan R.

unread,
Sep 13, 2005, 4:56:16 PM9/13/05
to
Martin Ouwehand wrote:
> In article <1126187763.9...@g44g2000cwa.googlegroups.com>,
> "Juan R." <juanrgo...@canonicalscience.com> writes:
>
> ] Now i will cite to Lorentz (1914):
> ]
> ] "I had not thought of the straight path leading to them, since I
> ] considered there was an essential difference between the reference
> ] systems x, y, z, t and x', y', z', t'. In one of them were used -
> ] such was my reasoning - coordinate axes with a definite position
> ] in ether and what could be termed true time; in the other, on the
> ] contrary, one simply dealt with subsidiary quantities introduced
> ] with the aid of a mathematical trick. Thus, for instance, the variable
> ] t' could not be called time in the same sense as the variable t.
> ] Given such reasoning, I did not think of describing phenomena in
> ] the reference system x', y', z', t' in precisely the same way, as
> ] in the reference system x, y, z, t"
>
> I would be grateful if you could give the full reference to this citation,
> which I find very interesting because it clearly shows that for Lorentz
> himself the transformation bearing his name was *not* relating space-time
> measurements of the same event in different inertial frames -- it is a
> "mathematical trick" concerning the "subsidiary quantities" x', t'.
> Although some people apparently think otherwise, I find it fairly obvious
> from reading Lorentz' 1904 article (which the above excerpt seems to be
> commenting), that he believes in galilean relativity plus FitzGerald-Lorentz
> contraction.

I think that the fact Lorentz failed to obtain relativity but was very
close is a standard. Also Einstein said basically that if one
substitutes Lorentz "local time" by a real time, one obtains SR from
Lorentz theory.

H. A. Lorentz, "Deux memoirs de Henri Poincaré" Acta mathematica 38,
(1921). In

11. Logunov, A. A; Mestvirishvili, M. A; Petrov, V. A. arXiv 2004,
physics/0405075 v3.

it is explained that article was prepared in 1914 but printing delayed
to 1921 due to War.

> I think Poincaré did too: for instance in his 1909 Conference
> he explains that a ligth wavefront, spherical in one frame, would *appear*
> ellipsoidal in another fame moving with respect to first, because of the
> contraction of the measuring rods -- and this is definitely different from
> Einstein's prediction that the wavefront would appear spherical in all
> inertial frames.

This is not correct. In fact, Poincaré clearly stipulates that
Galilean invariance may be abandoned. He clearly states that Lorentz
"local time" is a real time measured by clocks (i already cited this).

In above cited Lorentz article, Lorentz states that PoR was formulated
by Poincaré and also says that first 4D formulation of mechanics was
achieved by Poincaré before Minkowski and Einstein.

Lorentz is very clear but you cannot take part of his quote and
ignoring the rest. Exactly Lorentz says (i repeat again now with
*emphasis* added):

"I had not thought of the straight path leading to them, since I
considered there was an essential difference between the reference
systems x, y, z, t and x', y', z', t'."

"I did not think of describing phenomena in the reference system x',
y', z', t' *in precisely the same way*, as in the reference system x,
y, z, t... I later saw from the article by Poincaré... that..."

"the fundamental equation expressing this principle and the operations

used in derivation of the field equations *are identical* in systems x,


y, z, t and x', y', z', t'."

For me, Lorentz is clearly crediting Poincaré as the true father of
SR. In fact, was Lorenzt who rejected the idea of giving the Nobel
Prize to Einstein for relativity theory claiming that Poincaré did.
Since Poincaré had passed away, the Nobel committe decided to give the
Nobel to Einstein by photoelectric effect. I already noted this in past
posts.

I think that POincaré changed his view partially in 1908-1909, etc.
but does not imply that his writtings of 1902, 1904-1906 are absent
from study.

As already explained in the thread on history of relativity and
Poincaré, also Einstein recognized in posterior years that the LT does
NOT follow from two SR postulates alone, and in a letter to Lorentz
dated 17 June 1916, Einstein wrote (quoted in Miller, A. I. (1986)
Imagery in Scientific Thought: Creating twentieth-Century Physics
(Cambridge: MIT Press).p. 55):

"I agree with you that the general relativity theory admits of an ether
hypothesis as does the special relativity theory."

However, standard mainstream historical knowledge is that "Einstein
main achievement was the total abandon of aether whereas Poincaré
returned".

I am sorry but i cannot see nothing novel or revolutionary on
Einstein's 1905 work that is not available in previous literature. Let
me remark again that Einstein said that newer read Poincaré and 1904
Lorentz paper but two of his colleagues claim that Einstein read
Poincaré 1902 (7. Solovine M. Lettres à Maurice Solovine.
Gauthier-Villars: Paris, 1956.)

And as I already noted in previous posts, Einstein's 1905 paper uses
the same notation that Lorentz 1904 and begins the proof of LT from a
GALILEAN TRANSFORMATION (exactly like Lorentz did). Note that wavefront
is not spherical in x' because in Einstein 1905 words:

"If we place x'=x-vt, it is clear that a point at rest in the system k
must have a system of values x', y, z, independent of time."

Why did Einstein begin with a Galilean transformation?

Javier Bezos

unread,
Sep 15, 2005, 1:39:48 AM9/15/05
to
Perspicacious wrote:

> a more relevant question would
> be, "What were the contributions to relativity before
> and after Einstein?"

This is a good point. From the point of view of historical
research, in order to answer this we need to investigate known
antecedents, like the PoR as used by, say, Huygens, as well as
all the related literature published at the end of the 19th
century and the beginning of the 20th (Kaufmann, Abraham,
Langevin, Bucherer, Voigt, Larmor, etc.). We have to read all
letters written by Poincar=E9 and Einstein, too, and to understand
the methods, the terminology and the way physical phenomena were
understood. Note we need not only to discredit Einstein but the
generalized opinion of his time about the importance and novelty
of his writings (Planck, Lamb, Lorentz, Tolman, etc.)--and that
includes Poincar=E9, who wrote, in a enthusiastic recommendation,
that if only a few of Einstein's ideas turned out to be true he
would be a person of extraordinary importance:

http://www.edge.org/3rd_culture/galison03/galison_print.html

BTW, Einstein got the job (one of the jobs, in fact).

Just comparing only the papers written by Poincar=E9 and Lorentz
with those written by Einstein means to begin from the
conclusions, and this is nonsense as a historical research--may
be clues, but nothing more.

> Was Einstein's idea outrageously
> new and original or did he merely take the next logical
> baby step beyond previously existing ideas?

Why should things be black or white--either all Einstein said was
new or all Einstein said was known?

Javier
-----------------------------
http://www.texytipografia.com

Harry

unread,
Sep 15, 2005, 1:40:14 AM9/15/05
to
"Martin Ouwehand" <see...@end.of.post.ch> wrote in message
news:43254749$1...@epflnews.epfl.ch...

> In article <1126187763.9...@g44g2000cwa.googlegroups.com>,
> "Juan R." <juanrgo...@canonicalscience.com> writes:
>
> ] Now i will cite to Lorentz (1914):
> ]
> ] "I had not thought of the straight path leading to them, since I
> ] considered there was an essential difference between the reference
> ] systems x, y, z, t and x', y', z', t'. In one of them were used -
> ] such was my reasoning - coordinate axes with a definite position
> ] in ether and what could be termed true time; in the other, on the
> ] contrary, one simply dealt with subsidiary quantities introduced
> ] with the aid of a mathematical trick. Thus, for instance, the variable
> ] t' could not be called time in the same sense as the variable t.
> ] Given such reasoning, I did not think of describing phenomena in
> ] the reference system x', y', z', t' in precisely the same way, as
> ] in the reference system x, y, z, t"
>
> I would be grateful if you could give the full reference to this citation,
> which I find very interesting because it clearly shows that for Lorentz
> himself the transformation bearing his name was *not* relating space-time
> measurements of the same event in different inertial frames -- it is a
> "mathematical trick" concerning the "subsidiary quantities" x', t'.

Hi Martin, I'll forward it to you today (I myself received it yesterday, and
it was published in 1921 or so).

- The transformation bearing Lorentz' name is of Poincare, June 1905, and
Lorentz called them later "relativity transformations".
- In the following paragraph, Lorentz stressed that :
"POINCARE, to the contrary, has obtained a perfect invariance of the
electrodynamics equations, and he has formulated the "relativity postulate",
a term that he was the first to work with. In fact, *taking the point of
view that I missed*, he has found the formulas (4) and (7)." (quick
translation and emphasis mine)

> Although some people apparently think otherwise, I find it fairly obvious
> from reading Lorentz' 1904 article (which the above excerpt seems to be
> commenting), that he believes in galilean relativity plus
FitzGerald-Lorentz
> contraction.

I suppose you mean Newtonian relativity and Lorentz contraction as well as
mass increase?
Sure.

> I think Poincaré did too: for instance in his 1909 Conference
> he explains that a ligth wavefront, spherical in one frame, would *appear*
> ellipsoidal in another fame moving with respect to first, because of the
> contraction of the measuring rods -- and this is definitely different from
> Einstein's prediction that the wavefront would appear spherical in all
> inertial frames.

Perhaps it was a mistake, but more likely he meant something else than
Einstein (for example the wavefront as pictured in the other frame).
Anyway, I agree again with you that Poincare adopted Lorentz' point of
view and not that of Einstein: Einstein even dared to claim that
Poincare didn't understand relativity, as Poincare disagreed with his
point of view.

Best regards,
Harald

Javier Bezos

unread,
Sep 15, 2005, 1:40:23 AM9/15/05
to
Homo Lykos wrote:

> > Read chap. 28 of Feynman's Lectures on Physics to understand
> > why there is a contradiction.
>
> It's very new to me that Feynman is expert in history. After
> all I know, he himself never said this. In contrast I remember
> that somewhere he explicitely claimed, that he knows history of
> science not by original papers.

At least he knew Poincar=E9 formulated the PoR, as chapter 29
begins with the PoR by "Poincar=E9 and Einstein". Anyway, the
contradiction is not historical but physical. Chapter 28 helps
to understand how physicists undestood electromagnetic mass
at the beginning of the 20th century.

> Poincar=E9 and Lorentz NOT assumed different transformation rules


> for electromagnetic and mechanical masses: They claimed that

> all masses (forces) have to behave in the same manner; Poincar=E9


> especially emphasized that this has to be so if PoR is valid
> and such sentences you don't find for the first time 1905, but

> you can find similar statements of Poincar=E9 already in 1904,


> before he had read the article of Lorentz.

They assumed different transformation rules, indeed. Poincar=E9,
in the light of his PoR, then said machanical mass _might_ be
equal to electromagnetical mass, but he tried to modify
gravitation so that it behaved like electromagnetism, which, given
how Newton's laws were revered at the time, was a _very bold_ step
(perhaps even bolder than Eintein's) -- unfortunately, that bold
step was a wrong step.

> > Einstein's step was a bold step and closed definitely the issue.
>

> Nonsense again: I cite the only sentence in this context I found now in=


the
> SR-paper of Einstein of 30 june 1905:
>

> " Wir bemerken, da=DF diese Resultate =FCber die [longitudinale und
> transversale] Masse auch f=FCr die ponderablen materiellen Punkte gilt
> [gelten]; denn ein Punkt kann durch Zuf=FCgen einer beliebig kleinen
> elektrischen Ladung zu einem Elektron (in unserem Sinne) gemacht werden=


. "
> (view [E1], page 919 in http://www.soso.ch/wissen/hist/SRT/srt.htm)

(English version, as many people can't read German:

We remark that these results as to the mass are also valid for
ponderable material points, because a ponderable material point
can be made into an electron (in our sense of the word) by the

addition of an electric charge, no matter how small.)


>
>> For me a very dark explanation, *extremely* far from a bold step.

Very dark, indeed. But the fact is that in the paper there
is only a mass, that he showed that electromagnetic mass
can be ignored somehow and that he gave that step.

> On the other hand: For me this is one of the sentences in Einsteins pap=
er,
> which seem me to show that Einstein probably has known - before finsish=
ing
> his paper - the articles of Poincar=E9 (and Lorentz), where he could fi=


nd all
> most important results of his own paper.

I don't see why--this paragraph could show Einstein knew
Abraham's theories. On the other hand, that would mean Poincar=E9's and
Eintein's theories are the same, while
they aren't.

Javier
-----------------------------
http://www.texytipografia.com

Harry

unread,
Sep 15, 2005, 1:41:18 AM9/15/05
to
"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1126595987.0...@g43g2000cwa.googlegroups.com...

Of course I didn't reproduce the whole article. I find your take on
magnetic charge interesting as I never heard of such a thing, what are
the units of magnetic charge? I also notice that you snipped my main
point (about the "bold step") and did not comment on it.

Best regards,
Harald

Igor Khavkine

unread,
Sep 15, 2005, 1:41:39 AM9/15/05
to
Juan R. wrote:

> For me, Lorentz is clearly crediting Poincar=E9 as the true father of


> SR. In fact, was Lorenzt who rejected the idea of giving the Nobel

> Prize to Einstein for relativity theory claiming that Poincar=E9 did.
> Since Poincar=E9 had passed away, the Nobel committe decided to give th=


e
> Nobel to Einstein by photoelectric effect. I already noted this in past
> posts.

Is this documented somewhere? I recall another poster mentioning that
the Nobel committee didn't make their deliberations public.

Igor

Javier Bezos

unread,
Sep 15, 2005, 10:03:28 AM9/15/05
to
Homo Lykos wrote:

>> Poincaré published three papers with the same title
>> in 1905, 1906 and 1908, iirc.
>
> This is not correct so:

Almost:

Poincaré, J. Henri: "Sur la Dynamique de l'Électron". Comptes
rendus de l&#8217;Académie des Sciences 140, 1504-1508 (1905).

Poincaré, J. Henri: "Sur la Dynamique de l'Électron". Rendiconti
del Círcolo matemático di Palermo 21, 129-176 (1906).

Poincaré, J. Henri: "La Dynamique de l'Électron". Revue genérale
des Sciences pures et apliques 19, 386-402 (1908).

I don't see the point for this "correction", as the only
difference in the last paper is the word "Sur" ("On") and their
titles are essentially the same.

>>> This is *no* contradiction, because Poincaré and nobody else

>>> [...]


>>
>> Read chap. 28 of Feynman's Lectures on Physics to understand
>> why there is a contradiction.
>

> It's very new to me that Feynman is expert in history. [...]

The contradiction is not historical but physical, and Poincaré
himself explains it in the paper! (pp. 537-9). Since the
solution Poincaré proposed required a new law of gravitation,
which turned out to be wrong, the contradiction remains. So,
if you think there is no contradiction, clearly you don't
share Poincaré's theories.

> Poincaré and Lorentz NOT assumed different transformation rules
> for electromagnetic and mechanical masses: They claimed that
> all masses (forces) have to behave in the same manner; Poincaré
> especially emphasized that this has to be so if PoR is valid
> and such sentences you don't find for the first time 1905, but
> you can find similar statements of Poincaré already in 1904,
> before he had read the article of Lorentz.

They assumed different transformation rules, indeed. Poincaré,
in the light of his PoR, then stated mechanical mass _might_ be


equal to electromagnetical mass, but he tried to modify

gravitation so that it behaved like electromagnetism (his "new
dynamics"?). Given how Newton's laws were revered at the time
that was a _very bold_ step (perhaps even bolder than Eintein's,
even if he wasn't the first to propose the modification), but
unfortunately that bold step was a wrong step.

> > Einstein's step was a bold step and closed definitely the issue.
>
> Nonsense again: I cite the only sentence in this context I found now in the
> SR-paper of Einstein of 30 june 1905:
>
> " Wir bemerken, daß diese Resultate über die [longitudinale und
> transversale] Masse auch für die ponderablen materiellen Punkte gilt
> [gelten]; denn ein Punkt kann durch Zufügen einer beliebig kleinen
> elektrischen Ladung zu einem Elektron (in unserem Sinne) gemacht werden. "
> (view [E1], page 919 in http://www.soso.ch/wissen/hist/SRT/srt.htm)

(English version, because many people can't read German:

We remark that these results as to the mass are also valid for
ponderable material points, because a ponderable material point
can be made into an electron (in our sense of the word) by the
addition of an electric charge, no matter how small.)
>

>> For me a very dark explanation, *extremely* far from a bold step.

Very dark, indeed. But the true fact is in the paper there is only
a mass, that it showed that electromagnetic mass was unnecessary
and that Einstein gave that step. A real physical issue was over
and converted into just metaphysics -- explanations about several
masses weren't necessary any more and that simplified a lot the
development of new theories.

> On the other hand: For me this is one of the sentences in Einsteins paper,
> which seem me to show that Einstein probably has known - before finsishing
> his paper - the articles of Poincaré (and Lorentz), where he could find all
> most important results of his own paper.

I don't see why--this paragraph could show Einstein knew
Abraham's theories, for example. Even so, that would be relevant
if Poincaré and Eintein were saying the same things, but they
aren't. Einstein's ideas were original--as Poincaré put it:

M. Einstein est un des esprits les plus originaux que j'aie
connus ; malgré sa jeunesse, il a déjà pris un rang très
honorable parmi les premiers savants de son temps.

(http://www.univ-nancy2.fr/poincare/chp/text/weiss3.html)

Javier
-----------------------------
http://www.texytipografia.com


Harry

unread,
Sep 15, 2005, 10:03:32 AM9/15/05
to

"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1126618716.8...@g14g2000cwa.googlegroups.com...
> Homo Lykos wrote:
SNIP

> > Poincar=E9 and Lorentz NOT assumed different transformation rules
> > for electromagnetic and mechanical masses: They claimed that
> > all masses (forces) have to behave in the same manner; Poincar=E9
> > especially emphasized that this has to be so if PoR is valid
> > and such sentences you don't find for the first time 1905, but
> > you can find similar statements of Poincar=E9 already in 1904,
> > before he had read the article of Lorentz.
>
> They assumed different transformation rules, indeed.

SNIP

There may have been a kind of time lapse problem with the messages...
otherwise I can't explain JB's above reply *after* his reply to my posting
in which I had cited:

"Consequently, the proper relation between the forces and the
accelerations will exist in the two cases, if we suppose that the masses
of all particles are influenced by a translation to the same degree as

the electromagnetic masses of the electrons." -Lorentz 1904

Harald


cma...@yahoo.com

unread,
Sep 17, 2005, 12:15:36 PM9/17/05
to
Juan R. wrote:

[snip]

> And as I already noted in previous posts, Einstein's 1905 paper uses
> the same notation that Lorentz 1904 and begins the proof of LT from a
> GALILEAN TRANSFORMATION (exactly like Lorentz did). Note that wavefront
> is not spherical in x' because in Einstein 1905 words:
>
> "If we place x'=x-vt, it is clear that a point at rest in the system k
> must have a system of values x', y, z, independent of time."
>
> Why did Einstein begin with a Galilean transformation?

I find your posts interesting and I agree with you on most points, but
here is mistake. The quantity x' belongs to the system K at rest, not
to the system k in motion. View it this way: you're in system K and you
observe the evolving separation between stationary point x and the
moving origin of system k. The x' quantity is simply that separation,
in fact he could have written it as x'(t) to emphasize that point. To
an observer in k, x'(t) has no direct meaning. In that 1905 paper,
Einstein intends to map an event at x and t in K to an event at
greek_xi and greek_tau in k, but mathematically it's easier to do it by
actually mapping from x'(t) and t to greek_xi and greek_tau, and that's
why he used x' instead of x. That's all there is to it. It's just a
mathematical aid.

Chris

I.Vecchi

unread,
Sep 17, 2005, 12:15:42 PM9/17/05
to
Igor Khavkine ha scritto:

I read that "no official accounts of the meetings exist but a number of
archival sources provide insight into the event" ([3]).

Einstein got the price "for his services to Theoretical Physics, and
especially for his discovery of the law of the photoelectric effect"
([1]).

The claim about Lorentz rejecting "the idea of giving the Nobel Prize
to Einstein for relativity theory" is made in [2], without references.

There is avery readable article on "Einstein and the Nobel
Committee:Authority vs.Expertise" at [3], barely mentioning Lorentz but
telling quite an interesting story.

The following quote may give a flair of those times.

" There is probably no physicist living today whose name has become so
widely known as that of Albert Einstein. Most discussion centres on his
theory of relativity. This pertains essentially to epistemology and has
therefore been the subject of lively debate in philosophical circles. "
([4])

Cheers,

IV

[1] http://nobelprize.org/physics/laureates/1921/index.html
[2] http://www-cosmosaf.iap.fr/Poincare-RR3A.htm
[3] http://www.europhysicsnews.com/full/34/article5.pdf
[4] The Nobel Prize in Physics 1921, Presentation Speech by Professor
S. Arrhenius, Chairman of the Nobel Committee for Physics of the Royal
Swedish Academy of Sciences, on December 10, 1922 at
http://nobelprize.org/physics/laureates/1921/press.html

Javier Bezos

unread,
Sep 17, 2005, 12:15:48 PM9/17/05
to
Harry wrote:

> Of course I didn't reproduce the whole article. I find your take on
> magnetic charge interesting as I never heard of such a thing, what are
> the units of magnetic charge?

The old times of the three CGS systems... Formerly (perhaps
until middle 20th C.), magnetic charge was a customary
way to present the laws of magnetisms, even if considered
ficticiuos. I don't remember right now if the unit had
a name (like the franklin for electric charge), but I
IIRC it had not. One could write a (huge) book on the
history of EM units (BTW, is there such a book?).


> I also notice that you snipped my main
> point (about the "bold step") and did not comment on it.

I've send two similar messages with minor changes in
answer to Homo Lykos, because the first one didn't
arrived after almost two days. The second one, which
is more complete thanks to I had time to verify a few
things and references (in particular to reread the
Poincare's paper as I was pretty sure the contradiction
was explained by Poicare himself), explains one of
the possible reasons why after the Eisteins paper there
were a lot of new developments (Pauli gives lots of
references) -- the real physical issue at the time
about two masses was over and converted into just
metaphysiscs, so that it could be completely ignored.

Javier
-----------------------------
http://www.texytipografia.com

Javier Bezos

unread,
Sep 17, 2005, 12:16:36 PM9/17/05
to
Harry wrote:

> There may have been a kind of time lapse problem with the messages...
> otherwise I can't explain JB's above reply *after* his reply to my posting
> in which I had cited:

Perhaps it's my fault, because I realized I send a couple
of messages as a new thread and without subject. My
apologies, and I'll be more careful in the future.

Javier
-----------------------------
http://www.texytipografia.com

Harry

unread,
Sep 17, 2005, 12:17:55 PM9/17/05
to
"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1126724752.3...@g43g2000cwa.googlegroups.com...
SNIP

Einstein's ideas were original--as Poincaré put it:
>
> M. Einstein est un des esprits les plus originaux que j'aie
> connus ; malgré sa jeunesse, il a déjà pris un rang très
> honorable parmi les premiers savants de son temps.
>
> (http://www.univ-nancy2.fr/poincare/chp/text/weiss3.html)
>

Thanks! There he also specified what Einstein was particularly good at:

" Ce que nous devons surtout admirer en lui, c'est la facilité avec laquelle
il s'adapte aux conceptions nouvelles et sait en tirer toutes les
conséquences. Il ne reste pas attaché aux principes classiques, et, en
présence d'un problème de physique, est prompt à envisager toutes les
possibilités. "

"What we must especially admire in him, is the facility with which he adapts
to the new designs and knows how to obtain all the consequences from them.
He does not remain attached to the classical principles, and, in the
presence of a physics problem, is prompt to consider all the
possibilities." - Altavista, corrected

Harald

Homo Lykos

unread,
Sep 17, 2005, 2:09:46 PM9/17/05
to
"Javier Bezos" <see_belo...@yahoo.es> schrieb im Newsbeitrag
news:1126724752.3...@g43g2000cwa.googlegroups.com...

> Homo Lykos wrote:
>
>>> Poincaré published three papers with the same title
>>> in 1905, 1906 and 1908, iirc.
>>
>> This is not correct so:
>
> Almost:
>
> Poincaré, J. Henri: "Sur la Dynamique de l'Électron". Comptes
> rendus de l&#8217;Académie des Sciences 140, 1504-1508 (1905).
>
> Poincaré, J. Henri: "Sur la Dynamique de l'Électron". Rendiconti
> del Círcolo matemático di Palermo 21, 129-176 (1906).
>
> Poincaré, J. Henri: "La Dynamique de l'Électron". Revue genérale
> des Sciences pures et apliques 19, 386-402 (1908).
>
> I don't see the point for this "correction", as the only
> difference in the last paper is the word "Sur" ("On") and their
> titles are essentially the same.

The important point you have erased:

" The paper of 5 june 1905 is only a relatively long "abstract" of the
SR-paper of 23 july 1905 with *all* most important results of the 23
july-paper for priority reasons - as I think - because Poincaré has known of
course that up to the appearance of the mainpaper in the rendiconti one had
to wait a long time. "

>


> The contradiction is not historical but physical,

See also Harrys answer.

> and Poincaré
> himself explains it in the paper! (pp. 537-9). Since the
> solution Poincaré proposed required a new law of gravitation,
> which turned out to be wrong, the contradiction remains.

Poincaré had "half" success in explaining and not only demanding that
electric and mechanical masses behave in the same way. Einsteins
"explanation" was nothing in comparison with Poincaré, as I showed with my
citation in my last note, and Einsteins sentence shows very clearly that
Einstein had the strong feeling, that he too should explain that electric
and mechanical masses behave in the same way; he has obviously not known at
this time, that he had solved this problem, as you claim.

To gravitation: It was the first attempt to make a lorentz-covariant theory
of gravitation, a really great step, which was not fully correct, but which
could show important features of a special lorentz-covariant gravitational
theory for the first time. And his main-conclusion of 5 june 1905 remained
valid.


> but he tried to modify
> gravitation so that it behaved like electromagnetism (his "new
> dynamics"?). Given how Newton's laws were revered at the time
> that was a _very bold_ step (perhaps even bolder than Eintein's,
> even if he wasn't the first to propose the modification

You speak of the paper of 1908? Who proposed before a lorentz-covariant
gravitation theory? This was the great step of Poincaré of 5 june 1905.
Theories in analogy to electromagnetism (e.g. of Weber) for the explanation
of the perihelion shift existed before, thats correct and this says Poincaré
1908 himself.

), but
> unfortunately that bold step was a wrong step.

It's a pity, that nobody followed this way: Probably it had been possible to
find so in a second step gravitomagnetic field equations.

And don't forget: Einsteins GR on large scales is very probably also (fully)
wrong.

>
>> > Einstein's step was a bold step and closed definitely the issue.
>>
>> Nonsense again: I cite the only sentence in this context I found now in
>> the
>> SR-paper of Einstein of 30 june 1905:
>>
>> " Wir bemerken, daß diese Resultate über die [longitudinale und
>> transversale] Masse auch für die ponderablen materiellen Punkte gilt
>> [gelten]; denn ein Punkt kann durch Zufügen einer beliebig kleinen
>> elektrischen Ladung zu einem Elektron (in unserem Sinne) gemacht werden.
>> "
>> (view [E1], page 919 in http://www.soso.ch/wissen/hist/SRT/srt.htm)
>
> (English version, because many people can't read German:
>
> We remark that these results as to the mass are also valid for
> ponderable material points, because a ponderable material point
> can be made into an electron (in our sense of the word) by the
> addition of an electric charge, no matter how small.)
>>
>>> For me a very dark explanation, *extremely* far from a bold step.
>
> Very dark, indeed. But the true fact is in the paper there is only
> a mass, that it showed that electromagnetic mass was unnecessary
> and that Einstein gave that step.

You may see this step; Einstein in june 1905 did not, as this sentence of
Einstein very clearly proofs.

> Einstein's ideas were original--as Poincaré put it:
>
> M. Einstein est un des esprits les plus originaux que j'aie
> connus ; malgré sa jeunesse, il a déjà pris un rang très
> honorable parmi les premiers savants de son temps.

Your conclusion concerning SR is absolutely wrong:

In connection with SR Poincaré never mentioned Einstein in his papers and
this was on purpose. This text here is the begin of a reference ETH had
asked for, if I correctely remember, before Einstein became professor at the
ETH, and this text shows that Poincaré generally estimated Einstein, but it
sais nothing about Einstein and SR.


Homo Lykos


Javier Bezos

unread,
Sep 19, 2005, 5:55:36 PM9/19/05
to
Homo Lykos wrote:

> >>> Poincar=E9 published three papers with the same title


> >>> in 1905, 1906 and 1908, iirc.

> The important point you have erased:


>
> " The paper of 5 june 1905 is only a relatively long "abstract" of the
> SR-paper of 23 july 1905 with *all* most important results of the 23

[...]

I just said Poincar=E9 published three papers, that's all. If
that's wrong, I'll rectify, but your answer has no relation
with that and it reveals you are mainly interested in contradict.

> he has obviously not known at this time, that he had
> solved this problem, as you claim.

Thanks. So, he solved the problem (even if he was not
aware of that).

> > dynamics"?). Given how Newton's laws were revered at the time
> > that was a _very bold_ step (perhaps even bolder than Eintein's,
> > even if he wasn't the first to propose the modification
>
> You speak of the paper of 1908? Who proposed before a lorentz-covariant
> gravitation theory?

I haven't said that a gravitation theory was proposed before.
What I've said is he proposed the law of gravitation should
be modified (something Lorentz proposed before).

> Your conclusion concerning SR is absolutely wrong:

> In connection with SR Poincar=E9 never mentioned Einstein in his papers

Who did say that?

Javier
-----------------------------
http://www.texytipografia.com

Juan R.

unread,
Sep 19, 2005, 5:55:51 PM9/19/05
to
cma...@yahoo.com wrote:
> Juan R. wrote:
>
> [snip]
>
> > And as I already noted in previous posts, Einstein's 1905 paper uses
> > the same notation that Lorentz 1904 and begins the proof of LT from a
> > GALILEAN TRANSFORMATION (exactly like Lorentz did). Note that wavefro=

nt
> > is not spherical in x' because in Einstein 1905 words:
> >
> > "If we place x'=3Dx-vt, it is clear that a point at rest in the syste=

m k
> > must have a system of values x', y, z, independent of time."
> >
> > Why did Einstein begin with a Galilean transformation?
>
> I find your posts interesting and I agree with you on most points, but
> here is mistake. The quantity x' belongs to the system K at rest, not
> to the system k in motion. View it this way: you're in system K and you
> observe the evolving separation between stationary point x and the
> moving origin of system k. The x' quantity is simply that separation,
> in fact he could have written it as x'(t) to emphasize that point. To
> an observer in k, x'(t) has no direct meaning. In that 1905 paper,
> Einstein intends to map an event at x and t in K to an event at
> greek_xi and greek_tau in k, but mathematically it's easier to do it by
> actually mapping from x'(t) and t to greek_xi and greek_tau, and that's
> why he used x' instead of x. That's all there is to it. It's just a
> mathematical aid.
>
> Chris

Thanks Chris,

Is it true that x' is a mathematical aid or has physical sense? I think
that Einstein uses with full physical sense. Note that x' is defined in
terms of physical quantities. On any case, Einstein is a bit ambiguous
here

"it is clear that a point at rest in the system k must have a system of
values x', y, z, independent of time."

and i wait that people that critiques ambiguity of certain last
Poincar=E9's works recognizes that Einstein is also ambiguous.

However, i think that rest of my comment may be still interesting. He
begins like Lorentz and i find that very curious if Einstein newer read
Lorentz works after 1895. Einstein also use the same notation that
Lorentz in his 1904 paper.

Juan R.

Cetner for CANONICAL |SCIENCE)

Harry

unread,
Sep 20, 2005, 10:35:04 AM9/20/05
to

"Javier Bezos" <see_belo...@yahoo.es> wrote in message
news:1127031732.8...@g47g2000cwa.googlegroups.com...
> Homo Lykos wrote:
SNIP

> > Your conclusion concerning SR is absolutely wrong:
> > In connection with SR Poincar=E9 never mentioned Einstein in his papers
>
> Who did say that?

I also read that but forgot where.
Anyway, I myself also never read a passage of Poincare about the new
mechanics in which he mentioned Einstein. I have no doubt that he did that
purposefully.

Harald


Homo Lykos

unread,
Sep 21, 2005, 3:04:53 AM9/21/05
to
"Harry" <harald.v...@epfl.ch> schrieb im Newsbeitrag
news:432fe5e3$1...@epflnews.epfl.ch...

>
> "Javier Bezos" <see_belo...@yahoo.es> wrote in message
> news:1127031732.8...@g47g2000cwa.googlegroups.com...
>> Homo Lykos wrote:
> SNIP
>
>> > Your conclusion concerning SR is absolutely wrong:
>> > In connection with SR Poincar=E9 never mentioned Einstein in his papers
>>
>> Who did say that?
>
> I also read that but forgot where.

1. Pais, chapter 8, Poincaré and Einstein.

2. Scott Walter, "Minkowski, ... ", pages 56-58, especially page 57 at
bottom and 58 at top with footnote 38 in

http://www.univ-nancy2.fr/DepPhilo/walter/papers/einstd7.pdf

> Anyway, I myself also never read a passage of Poincare about the new
> mechanics in which he mentioned Einstein. I have no doubt that he did that
> purposefully.

There can be no doubt about this.


Homo Lykos

Martin Ouwehand

unread,
Sep 21, 2005, 4:54:14 PM9/21/05
to
In article <1126626847.8...@g43g2000cwa.googlegroups.com>,
"Juan R." <juanrgo...@canonicalscience.com> writes:

] Lorentz is very clear but you cannot take part of his quote and


] ignoring the rest. Exactly Lorentz says (i repeat again now with
] *emphasis* added):
]
] "I had not thought of the straight path leading to them, since I
] considered there was an essential difference between the reference
] systems x, y, z, t and x', y', z', t'."
]
] "I did not think of describing phenomena in the reference system x',
] y', z', t' *in precisely the same way*, as in the reference system x,
] y, z, t... I later saw from the article by Poincaré... that..."
]
] "the fundamental equation expressing this principle and the operations
] used in derivation of the field equations *are identical* in systems x,
] y, z, t and x', y', z', t'."

this alludes to the fact that Lorentz didn't use the "correct" transformation
law for the charge density and the current, while those found by Poincaré
are such that the Maxwell equations after the transformation are indeed
the same as in the ether frame.

It doesn't mean that Lorentz is saying that Poincaré realised that the
transformation relate space-time measurements in two inertial frames,
and there are some internal clues in Poincaré's 1905 and 1906 articles
that indeed he didn't take this point of view, e.g.: "[with the help of
the Lorentz transformation], two systems, one at rest, the other moving,
become exact copies of each other" whereas, if Poincaré had discoverd SR,
he would have said something like "the observations of a given system in
two different frames are related through the Lorentz transformation".
Another example: "the Lorentz transformation replaces the real electron
in motion by an ideal electron at rest."

To me, for Poincaré in his 1905-1906 articles, as for Lorentz in his
1904 article, the Lorentz transformation is an abstract transformation,
a mathematical help to show that the Lorentz contraction will be enough
to explain null results like the Michelson experience to all orders in
v/c.

] I think that Poincaré changed his view partially in 1908-1909, etc.

in the 1908-1909 articles, Poincaré at least expounds a theory of
space-time based on measurements made by obsverers, something that
is missing in the 1905-1906 papers. It is definitely not the same as
Einstein's. For instance in his 1908 article (available from
http://www.soso.ch/wissen/hist/SRT/srt.htm -- BTW thank you Homo Lykos
for the link !), I understand from his arguments around pages 565-566
that he uses the following transformation:

x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz contraction)
t' = t - (v * x) / (c^2 - v^2) ("local time")

(x', t') is what is actually measured by an observer in motion with respect
to the ether, (x, t) are the coordinates in the ether frame (beware that
in his formula for the local time, he expresses x in term of x', resulting
in a slightly different formula). With the help of this transformation, he
is able to explain the null result of the Michelson experience: the time
of travel of a light pulse along a given distance doesn't depend on the
direction. But the transformation rule for the speed of light (last
equation on page 566 -- BTW there is a misprint: t should be replaced
by tau) is:

c' = c * sqrt(1 - v^2/c^2)

which doesn't respect the principle of relativity (by measuring the speed
of light in different frames, it's possible to tell which is moving fastest
whith respect to the ether.)

] but does not imply that his writtings of 1902, 1904-1906 are absent
] from study.

you seem to be saying that after discovering Special Relativity in 1905,
he changed his mind... It is easy to see that what is missing in his 1908
article is time dilatation: do you know of an earlier reference where
Poincaré actually mentions it *in words* and says something like "Hey !
motion has an influence on the *rate* of clocks !" ?

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|_____________ Email/PGP: http://slwww.epfl.ch/info/Martin.html _____________

So please, oh please, we beg, we pray,
Go throw your TV set away [Roald Dahl]

Harry

unread,
Sep 22, 2005, 1:05:07 PM9/22/05
to

"Martin Ouwehand" <see...@end.of.post.ch> wrote in message
news:43313e74$1...@epflnews.epfl.ch...

> In article <1126626847.8...@g43g2000cwa.googlegroups.com>,
> "Juan R." <juanrgo...@canonicalscience.com> writes:
>
> ] Lorentz is very clear but you cannot take part of his quote and
> ] ignoring the rest. Exactly Lorentz says (i repeat again now with
> ] *emphasis* added):
> ]
> ] "I had not thought of the straight path leading to them, since I
> ] considered there was an essential difference between the reference
> ] systems x, y, z, t and x', y', z', t'."
> ]
> ] "I did not think of describing phenomena in the reference system x',
> ] y', z', t' *in precisely the same way*, as in the reference system x,
> ] y, z, t... I later saw from the article by Poincaré... that..."
> ]
> ] "the fundamental equation expressing this principle and the operations
> ] used in derivation of the field equations *are identical* in systems x,
> ] y, z, t and x', y', z', t'."
>
> this alludes to the fact that Lorentz didn't use the "correct"
transformation
> law for the charge density and the current, while those found by Poincaré
> are such that the Maxwell equations after the transformation are indeed
> the same as in the ether frame.
>
> It doesn't mean that Lorentz is saying that Poincaré realised that the
> transformation relate space-time measurements in two inertial frames,

That is correct, but that he realised that it relates distance and duration
measurements in inertial frames is clear from his detailed discussions and
explanations in earlier papers (as was shown in some recent postings).

> and there are some internal clues in Poincaré's 1905 and 1906 articles
> that indeed he didn't take this point of view, e.g.: "[with the help of
> the Lorentz transformation], two systems, one at rest, the other moving,
> become exact copies of each other"

If he meant with that the description of observations in those systems (the
laws of physics), I agree.

> whereas, if Poincaré had discoverd SR,
> he would have said something like "the observations of a given system in
> two different frames are related through the Lorentz transformation".

I also agree with that kind of statement. Thus I demonstrated that your
above assumption about what he would have said is unfounded. What else do
you think he meant?

> Another example: "the Lorentz transformation replaces the real electron
> in motion by an ideal electron at rest."

I also agree with that statement: an electron in motion is easier (ideally)
described by transforming to the rest frame of the electron, after which it
can be described as being in rest.

> To me, for Poincaré in his 1905-1906 articles, as for Lorentz in his
> 1904 article, the Lorentz transformation is an abstract transformation,
> a mathematical help to show that the Lorentz contraction will be enough
> to explain null results like the Michelson experience to all orders in
> v/c.

It's true that Lorentz didn't clearly notice the difference between on the
one hand a transformation as mathematical aid for calculations but in which
nothing happens (as Voigt had done, and as he considered to be the case with
"time"), and on the other hand a real physical change, such as he proposed
with length contraction of everything including the earth.
But if you search between the postings of the last two months you will see
that Poincare was not confused about this distinction.
Evidently, many people still don't understand the difference, and I am
puzzled by the above statement where "an abstract transformation" is put in
the same bucket as a reduction of the earth's diameter in the direction of
motion.

> ] I think that Poincaré changed his view partially in 1908-1909, etc.
>
> in the 1908-1909 articles, Poincaré at least expounds a theory of
> space-time based on measurements made by obsverers, something that
> is missing in the 1905-1906 papers.

There is no need to repeat incessantly what has been expounded before in
detail, and today the same applies -
as Juan R. recently wrote in the thread about the history (but perhaps you
did not see that thread?):

" [...] I already CITED his work where
Poincaré states that local time is a real time and Poincaré even
defined it in terms of clocks, like Einstein did after. I cannot repeat
the cites and references each time that i wrote here. You would read
with care previous posts before reply.".

> It is definitely not the same as
> Einstein's. For instance in his 1908 article (available from
> http://www.soso.ch/wissen/hist/SRT/srt.htm -- BTW thank you Homo Lykos
> for the link !),

BTW, also that german link reminds us of the fact that Poincare spoke about
real clocks and not just about mathematical manipulations:
"Im zweiten Büchlein findet man als Kapitel 2 wieder seine Arbeit von 1898
über die Zeitmessung, wo er das Konzept der Relativität der Gleichzeitigkeit
erstmals deutlich formuliert hat"

> I understand from his arguments around pages 565-566
> that he uses the following transformation:
>
> x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz contraction)
> t' = t - (v * x) / (c^2 - v^2) ("local time")
>
> (x', t') is what is actually measured by an observer in motion with
respect
> to the ether, (x, t) are the coordinates in the ether frame (beware that
> in his formula for the local time, he expresses x in term of x', resulting
> in a slightly different formula). With the help of this transformation, he
> is able to explain the null result of the Michelson experience: the time
> of travel of a light pulse along a given distance doesn't depend on the
> direction. But the transformation rule for the speed of light (last
> equation on page 566 -- BTW there is a misprint: t should be replaced
> by tau) is:
>
> c' = c * sqrt(1 - v^2/c^2)
>
> which doesn't respect the principle of relativity (by measuring the speed
> of light in different frames, it's possible to tell which is moving
fastest
> whith respect to the ether.)

That's amazing - even more as it's in the very paragraph where he advertises
the PoR, and as he ends that paragraph with the words that the compensation
is rigorous (it's the next sentence...)!
I have not studied it yet; but, just looking at the printing:
- I did not see the misprint (duration= t, apparent duration= tau), but the
last AB on the copy certainly was AB'.
- he did not write V' = V * sqrt(1 - v^2/V^2), and obviously he didn't
suggest such a weird thing.

> ] but does not imply that his writtings of 1902, 1904-1906 are absent
> ] from study.
>
> you seem to be saying that after discovering Special Relativity in 1905,
> he changed his mind... It is easy to see that what is missing in his 1908
> article is time dilatation:

I am flabbergasted - "time dilatation" is represented by the tau on page
566.

> do you know of an earlier reference where
> Poincaré actually mentions it *in words* and says something like "Hey !
> motion has an influence on the *rate* of clocks !" ?

I also don't remember having seen that he expressed that in words.
Maybe Einstein was the first to verbally point out that the effect on clocks
implies that "moving clocks" "go more slowly"?

Cheers,
Harald


Juan R.

unread,
Sep 23, 2005, 3:57:50 PM9/23/05
to
Martin Ouwehand wrote:

> this alludes to the fact that Lorentz didn't use the "correct" transformation
> law for the charge density and the current, while those found by Poincaré
> are such that the Maxwell equations after the transformation are indeed
> the same as in the ether frame.

i post before only part of the quote by Lorentz. The total is

"These considerations published by myself in 1904, have stimulated
Poincaré to write his article on the dynamics of electron where he
has given my name to the just mentioned transformation. I have to note
as regards this that a similar transformation have been already given
in an article by Voigt published in 1887 and I have not taken all
possible benefit from it. Indeed I have not given the most appropriate
transformation for some physical quantities encountered in
the formulae. This was done by Poincare and later by Einstein and
Minkowski[...] I had not thought of the straight path leading to them,
since I considered there WAS an essential difference between the
reference systems x, y, z, t and x', y', z', t'. In one of them were


used - such was my reasoning - coordinate axes with a definite
position in ether and what could be termed true time; in the other, on
the contrary, one simply dealt with subsidiary quantities introduced
with the aid of a mathematical trick. Thus, for instance, the variable
t' could not be called time in the same sense as the variable t. Given

such reasoning, I did not think of describing phenomena in the
reference system x', y', z', t' in precisely the SAME WAY, as in the
reference system x, y, z, t[...] I later saw from the article by
Poincare that, if I had acted in a more systematic manner, I could have
achieved an even more significant simplification. Having not noticed
this, I was not able to achieve total invariance of the equations; my
formulae remained cluttered up with excess terms, that should have
vanished. These terms were too small to influence phenomena noticeably,
and by this fact I could explain their independence of the Earth's
motion, revealed by observations, but I did not establish the
relativity principle as a rigorous and universal truth. On the
contrary, Poincare achieved total invariance of the equations of
electrodynamics and formulated the relativity postulate - a term
first introduced by him[...] I may add that, while thus correcting THE
DEFECTS OF MY work [after noted by Einstein -i already cited- that SR
basically follows from Lorentz relativity once corrected Lorentz error
with the concept of time], he never reproached me for them. I am unable
to present here all the beautiful results obtained by Poincare.
Nevertheless let me stress some of them. First, he DID NOT restrict
himself by demonstration that the RELATIVISTIC transformations left the
form of electromagnetic equations unchangeable [i.e. by use of real
time t']. He explained this success of transformations by the
opportunity to present these equations as a CONSEQUENCE of the least
action principle [a physical principle] and by the fact that the
FUNDAMENTAL equation expressing this principle and the OPERATIONS used
in derivation of the FIELD equations are IDENTICAL in SYSTEMS x, y, z,
t and x', y', z', t'[...] There are some NEW notions in this part of
the article, I should especially mark them. Poincare notes, for
example, that in consideration of quantities x, y, z, tsqr(-1) as
COORDINATES of a point in FOUR-dimensional space the relativistic
transformations reduces to rotations in this space. He also comes to
idea to add to the three components X, Y, Z of the force a quantity T =
Xa + Yb + Zc, which is nothing more than the work of the force at a
unit of time, and which may be treated as a fourth component of the
force in some sense. When dealing with the force acting at a unit of
volume of a body the RELATIVISTIC transformations change quantities X,
Y, Z, Tsqr(-1) in a similar way to quantities x, y, z, tsqr(-1). I
remind on these ideas by Poincare because they are closed to methods
LATER used by Minkowski and other
scientists to easing mathematical actions in the theory of relativity."

Lorentz says that error is he tought that local time was a mathematical
tool.

Lorentz clearly stipulates that was Poincaré who corrected this and
obtained full invariance by nothing that equations in both frames were
IDENTICAL ones. Lorentz also said that about Einstein work.

"The main reason of my failure was I always thought that only quantity
t could be treated as a true time and that my local time t' was
considered only as an auxiliary mathematical value. In the Einstein
theory, just opposite, t' is playing the same role as t. If we want to
describe phenomena as dependent on x', y', z', t', then we should
operate with these variables in just the same way as with x, y, z, t"

But the first to show this was Poincare

Also Poincaré proved the invariance of ds of the 4D, and it follows
that t and x cannot be absolute. Poincaré used other notation but

ds^2 = (cdt)^2 - (dx)^2

If ds is an invariant, t is not. Remember Poincaré words "time is
relative" I and other cited here.

I already CITED to Poincaré saying that Lorentz 'local time' was a
real time measured by a clock. Poincaré (1900):

"I assume observers, situated at different points, to compare their
clocks with the aid of light signals [...] The local time tau is the
time READ from the CLOCKS thus controlled."

Poincaré is correcting Lorentz error, and Lorentz noted this. AFTER
Einstein used the same operational definition of time as 'that'
measured by clocks.

> To me, for Poincaré in his 1905-1906 articles, as for Lorentz in his
> 1904 article, the Lorentz transformation is an abstract transformation,
> a mathematical help to show that the Lorentz contraction will be enough
> to explain null results like the Michelson experience to all orders in
> v/c.

for Poincaré the Lorentz transformation was not a mathematical tool
was the basis of a NEW mechanics that he developed: four-velocity,
four-force, new simultaneity, PoR, equations of motion, etc.

> ] I think that Poincaré changed his view partially in 1908-1909, etc.
>
> in the 1908-1909 articles, Poincaré at least expounds a theory of
> space-time based on measurements made by obsverers, something that

> is missing in the 1905-1906 papers. It is definitely not the same as


> Einstein's. For instance in his 1908 article (available from
> http://www.soso.ch/wissen/hist/SRT/srt.htm -- BTW thank you Homo Lykos

> for the link !), I understand from his arguments around pages 565-566


> that he uses the following transformation:
>
> x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz contraction)
> t' = t - (v * x) / (c^2 - v^2) ("local time")
>

> (x', t') is what is actually measured by an observer in motion with res=
pect
> to the ether, (x, t) are the coordinates in the ether frame (beware tha=
t
> in his formula for the local time, he expresses x in term of x', result=
ing
> in a slightly different formula). With the help of this transformation,=
he
> is able to explain the null result of the Michelson experience: the tim=


e
> of travel of a light pulse along a given distance doesn't depend on the
> direction. But the transformation rule for the speed of light (last
> equation on page 566 -- BTW there is a misprint: t should be replaced
> by tau) is:
>
> c' = c * sqrt(1 - v^2/c^2)
>

> which doesn't respect the principle of relativity (by measuring the spe=
ed
> of light in different frames, it's possible to tell which is moving fas=


test
> whith respect to the ether.)

also in posterior years Einstein changed his mind and aknowledge to
Lorentz that SR needs of an aether -I already cited this- If you reject
Poincaré in the basis of posterior work you would also reject Einstein
in the same basis.

Do not forget also that in posterior years Einsten said that c was NOT
a constant for properly studying gravitation (which was already being
studied by Poincaré so early as 1906). Then why if Poincaré was
studying gravitation AND relativity and was not sure about constancy of
c in an unified theory in 1908-09, and Einstein when in posterior years
studied gravity and initially though that c was not a constant that is
not a basis for critizing Einstein.

After Einstein changed AGAIN his view and now c is also constant in GR.
But what if Einstein has passed away in 1910-12? then now we had said
that Einstein thought that c was not constant, remember that Poincaré
died prematurely due to got cancer in 1909.

Other example, Einstein originally obtained GR without the 'trace
term', after receiving copy of Hilbert work submitted the 'final'
version of GR with the 1/2 'trace term'. In posterior years (1919) said
that WAS incorrect and substituted by a (1/4) [Tilman Sauer of the
Einstein Papers Project in arXiv:physics/0405066]. See the new version
of my document for details on this. If in posterior years Einstein said
the correct term was 1/4, why are not those posterior works used
against Einstein?

Again i see a double attitude when people omits many important data.

- Pauli early words are used against Poincaré but Pauli 1955 words
claiming that Poincaré obtained SR ignored.

- Lorentz words supporting Poincaré priority ignored but others
writings used in favor of Einstein.

- Poincaré posterior works used against Poincaré priority, but
Einstein posterior works (e.g. return to aether, non constancy of c)
ignored againt Einstein.

- It is argued that Einstein obtained SR from two postulates but in
posterior years own Einstein aknowledged that is not true (i already
cited additional hypothesis), etc.

- Each time that Poincaré is ambiguous, this is used against Poincaré
but ambiguity of Einstein writtings ignored. For example in Einstein
1905 SR article "If we place x'=x-vt, it is clear that a point at rest


in the system k must have a system of values x', y, z, independent of

time." At the best this is ambigous (a point at rest in moving frame
k?). By less that this Poincaré is attacked.

- Poincaré obtains the character of group but is claimed that do not
understand situation. Einstein claim that LT form a group (probably
read it in Poincaré works that claimed newer read but colleagues said
the contrary -i already cited-) but after do NOT use that character of
group (which implies that do not understand).

- Poincare states that c, light velocity is a universal constant.
Einstein says that c, the velocity of light in empty space, is an
universal constant, and people claim that Poincare said 'constant' but
mean 'non-constant'!

- Einstein: "light (as required by the principle of the constancy of
the velocity of light, in combination with the principle of relativity)
is also propagated with velocity c when measured in the moving system."
Next Einstein writes "But the ray moves relatively to the initial point
of k, when measured in the stationary system, with the velocity c-v"

- I have seen people attacking Lorentz and Poincaré and their ideas of
electron. Einstein write "A rigid body which, measured in a state of
rest, has the form of a sphere, therefore has in a state of
motion--viewed from the stationary system--the form of an ellipsoid of
revolution".

- A guy wrote here time ago that Poincaré had worked 'only' EM whereas
Einstein work was more general, including gravitation. But Poincare was
working in gravitation in 1906!!!!

- Minkowski and others clearly sipulated that v is always LESS than c.
Einstien wrote "For v=c all moving objects--viewed from the
'stationary' system--shrivel up into plane figures. For velocities
greater than that of light our deliberations become meaningless" But
did explcitely says that v = c was meaningless? Again wrote "Thus, when
v=c, W becomes infinite. Velocities greater than that of light have--as
in our previous results--no possibility of existence." But Einstein
said nothing about meaningless of v=c. SR is today explained in books
says that v < c.

That c is a limiting velocity was already said by Poincare -i already
cited-.

- Einstein: "It follows, further, that the velocity of light c cannot
be altered by composition with a velocity less than that of light."
Then, is Einstein claiming that when v is equal to c the velocity of
light c is altered?

- Einstein: "a spherical surface moving with the velocity of light
[...] We may therefore say that this surface permanently encloses the
same light complex [...] The spherical surface--viewed in the moving
system--is an ellipsoidal surface"

- Etc.

You may use the same criterion for all authors.

For instance, you claim that Poincaré wrote "[with the help of the


Lorentz transformation], two systems, one at rest, the other moving,

become exact copies of each other" whereas, if Poincaré had discoverd


SR, he would have said something like "the observations of a given
system in two different frames are related through the Lorentz
transformation".

Einstein said in 1948 (extracted from arXiv physics/0405075)

"With the AID of the Lorentz transformation the special relativity
principle CAN BE formulated as follows: the laws of Nature are
invariant with respect to the Lorentz transformation (i. e. a law of
Nature must not change, if it would be referred to a new inertial
reference system obtained with the AID of Lorentz transformation for x,
y, z, t)."

Compare with above Lorentz quote

"On the contrary, Poincare achieved total invariance of the equations
of electrodynamics and formulated the relativity postulate - a term
first introduced by him[...] First, he DID NOT restrict himself by
demonstration that the RELATIVISTIC transformations left the form of
electromagnetic equations unchangeable [i.e. by use of real time t'].
He explained this success of transformations by the opportunity to
present these equations as a CONSEQUENCE of the least action principle
[a physical principle] and by the fact that the FUNDAMENTAL equation
expressing this principle and the OPERATIONS used in derivation of the
FIELD equations are IDENTICAL in SYSTEMS x, y, z, t and x', y', z',
t'[...]"

where Lorentz recognizes that was Poincaré who showed that laws of
NATURE were invariant to the LT, due to "PoR + least action principle
of physics".

> ] but does not imply that his writtings of 1902, 1904-1906 are absent
> ] from study.
>

> you seem to be saying that after discovering Special Relativity in 1905=
,
> he changed his mind... It is easy to see that what is missing in his 19=
08
> article is time dilatation: do you know of an earlier reference where
> Poincaré actually mentions it *in words* and says something like "Hey=


!
> motion has an influence on the *rate* of clocks !" ?

I already cited his definition of 'local time' as clock rate. Since
Lorentz local time (Poincare's t') is different of t, rates of clocks
are different.

I and many others authors!!!! I have recopiled in the new version of my
previous document on history of relativity a lot of authors claiming
that SR was not obtained by Einstein. For example Pauli 1955 (who i
already cited here several times)

Now read my recent post Sep 21 on 'what is the history of...' thread
for another NEW support of 'my' thesis Poincare did basically all the
work

Jean Mawhin claims

"His books on Maxwell theory contain the germs of special relativity
and led him to analyze, CORRECT, and name the Lorentz transformations."

"[...] the mathematician Poincaré reached relativistic kinematics via
Maxwell's electromagnetic theory[...]"

Homo Lykos

unread,
Sep 24, 2005, 7:21:26 PM9/24/05
to
"Harry" <harald.v...@epfl.ch> schrieb im Newsbeitrag
news:43328457$1...@epflnews.epfl.ch...

>
> "Martin Ouwehand" <see...@end.of.post.ch> wrote in message
> news:43313e74$1...@epflnews.epfl.ch...
>> In article <1126626847.8...@g43g2000cwa.googlegroups.com>,
>> "Juan R." <juanrgo...@canonicalscience.com> writes:
>>
>
>> Another example: "the Lorentz transformation replaces the real electron
>> in motion by an ideal electron at rest."

It seems to me like a debate about words: Einstein also uses "ruhendes
System" (= system at rest) because of didactic reasons, and Poincaré used
ether because of didactic reasons and because he has known, that this is
allowed.

>
>> It is definitely not the same as
>> Einstein's. For instance in his 1908 article (available from
>> http://www.soso.ch/wissen/hist/SRT/srt.htm -- BTW thank you Homo Lykos
>> for the link !),
>
> BTW, also that german link reminds us of the fact that Poincare spoke
> about real clocks and not just about mathematical manipulations:
> "Im zweiten Büchlein findet man als Kapitel 2 wieder seine Arbeit von 1898
> über die Zeitmessung, wo er das Konzept der Relativität der
> Gleichzeitigkeit erstmals deutlich formuliert hat"
>
>> I understand from his arguments around pages 565-566
>> that he uses the following transformation:
>>
>> x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz contraction)
>> t' = t - (v * x) / (c^2 - v^2) ("local time")
>>
>> (x', t') is what is actually measured by an observer in motion with
>> respect to the ether, (x, t) are the coordinates in the ether frame
>> (beware that in his formula for the local time, he expresses x in term of
>> x', resulting in a slightly different formula). With the help of this
>> transformation, he is able to explain the null result of the Michelson
>> experience: the time of travel of a light pulse along a given distance
>> doesn't depend on the direction. But the transformation rule for the
>> speed of light (last equation on page 566 -- BTW there is a misprint: t
>> should be replaced by tau) is:
>>
>> c' = c * sqrt(1 - v^2/c^2)

Such a nonsense you don't find on page 566.

My interpretation (for the present) of this (strange) page 566:

1. This paper is written in a popular manner (almost no equations and
no real proofs, he don't makes use of setting V = 1 as in his papers of
1905)

2. His "popular proof" of Michelson/Morley seems to me with respect to his
own theory of 1905 incorrect. Especially strange for me:

" Supposons que la différence entre le temps vrai et le temp local en un
point quelconque soit égale à l'abscisse de ce point multipliée par la
constante: e/(V sqrt(1-e^2)) "

Poincaré gives no explanation for this (and speaks only of supposons(=we
suppose)) and I - at least in this moment - can't understand it.

3. If it is really only a (strange) error - as I believe now - it's not
possible to derive any conclusions.

>>
>> which doesn't respect the principle of relativity (by measuring the speed
>> of light in different frames, it's possible to tell which is moving
>> fastest whith respect to the ether.)
>

> - I did not see the misprint (duration= t, apparent duration= tau), but
> the last AB on the copy certainly was AB'.

No

>
>> do you know of an earlier reference where
>> Poincaré actually mentions it *in words* and says something like "Hey !
>> motion has an influence on the *rate* of clocks !" ?
>
> I also don't remember having seen that he expressed that in words.
> Maybe Einstein was the first to verbally point out that the effect on
> clocks implies that "moving clocks" "go more slowly"?

I think too, that Einsteins (popular) explanations of all these things were
clearer and more specific then the explanations of Poincaré; but from
Poincaré Einstein had first learned these more philosophical ideas about
space and time. Now I copy older citations of Poincaré in this context:

The strong general statement of 1898 in La Mesure du Temps:

" La simultanéité de deux événements, ou l'ordre de leur succession,
l'égalité de deux durées, doivent être définies de telle sorte que l`énoncé
des lois naturelles soit aussi simple que possible. "

More specifically 1904 in St. Louis (Bull. des Sciences Mathématiques,
deuxième Série, tomé XXVIII):

" .... Pour un observateur, entraîné lui-même dans une translation dont il
ne se doute pas, aucune vitesse apparente ne pourrait non plus dépasser
celle de la lumière; et ce serait là une contradiction, si l'on ne se
rappelait que cet observateur ne se servirait pas des mêmes horloges qu'un
observateur fixe, mais bien d'horloges marquant le "temps local". "


Homo Lykos


Homo Lykos

unread,
Sep 27, 2005, 3:36:43 PM9/27/05
to
Short addition:

"Homo Lykos" schrieb im Newsbeitrag news:4335d73e$1...@news.bluewin.ch...


>
> My interpretation (for the present) of this (strange) page 566:
>
> 1. This paper is written in a popular manner (almost no equations and
> no real proofs, he don't makes use of setting V = 1 as in his papers of
> 1905)
>
> 2. His "popular proof" of Michelson/Morley seems to me with respect to his
> own theory of 1905 incorrect. Especially strange for me:
>
> " Supposons que la différence entre le temps vrai et le temp local en un
> point quelconque soit égale à l'abscisse de ce point multipliée par la
> constante: e/(V sqrt(1-e^2)) "
>
> Poincaré gives no explanation for this (and speaks only of supposons(=we
> suppose)) and I - at least in this moment - can't understand it.
>
> 3. If it is really only a (strange) error - as I believe now - it's not
> possible to derive any conclusions.

4. His error is very probably, that he has written by mistake t instead of
tau in the last equation of page 566. So he believed to have shown the
following relation between true (t) and apparent duration (tau):
tau = t sqrt(1-e^2).
Only so I can understand the first sentence on page 567, which is directly
following the (wrong) equation for the apparent distance AB:

" c'est-à-dire que la durée apparente de transmission est proportionelle à
la distance apparente. "

Without this mistake one would have the following nonsense: tau = tau
sqrt(1-e^2).

Homo Lykos

Harry

unread,
Sep 27, 2005, 3:37:21 PM9/27/05
to
"Homo Lykos" <ly...@lykos.ch> wrote in message
news:4335d73e$1...@news.bluewin.ch...

Indeed.

> My interpretation (for the present) of this (strange) page 566:
>
> 1. This paper is written in a popular manner (almost no equations and
> no real proofs, he don't makes use of setting V = 1 as in his papers of
> 1905)
>
> 2. His "popular proof" of Michelson/Morley seems to me with respect to his
> own theory of 1905 incorrect.

Most likely (in general), that is due to a misunderstanding on your part.
I'll wait with giving my opinion until I understand how he meant it.

> Especially strange for me:
>
> " Supposons que la différence entre le temps vrai et le temp local en un
> point quelconque soit égale à l'abscisse de ce point multipliée par la
> constante: e/(V sqrt(1-e^2)) "
>
> Poincaré gives no explanation for this (and speaks only of supposons(=we
> suppose)) and I - at least in this moment - can't understand it.
>
> 3. If it is really only a (strange) error - as I believe now - it's not
> possible to derive any conclusions.
>
> >>
> >> which doesn't respect the principle of relativity (by measuring the
speed
> >> of light in different frames, it's possible to tell which is moving
> >> fastest whith respect to the ether.)
> >
> > - I did not see the misprint (duration= t, apparent duration= tau), but
> > the last AB on the copy certainly was AB'.
>
> No

Yes! He wrote that AB' was part of that equation. In the copy we only see AB
in that equation. I'm quite sure that AB' isn't AB with a beautiful piece of
dirt next to it at exactly the right spot. Thus the AB in the equation
certainly was AB'.

> >> do you know of an earlier reference where
> >> Poincaré actually mentions it *in words* and says something like "Hey !
> >> motion has an influence on the *rate* of clocks !" ?
> >
> > I also don't remember having seen that he expressed that in words.
> > Maybe Einstein was the first to verbally point out that the effect on
> > clocks implies that "moving clocks" "go more slowly"?
>
> I think too, that Einsteins (popular) explanations of all these things
were
> clearer and more specific then the explanations of Poincaré; but from
> Poincaré Einstein had first learned these more philosophical ideas about
> space and time. Now I copy older citations of Poincaré in this context:
>
> The strong general statement of 1898 in La Mesure du Temps:
>
> " La simultanéité de deux événements, ou l'ordre de leur succession,
> l'égalité de deux durées, doivent être définies de telle sorte que
l`énoncé
> des lois naturelles soit aussi simple que possible. "
>
> More specifically 1904 in St. Louis (Bull. des Sciences Mathématiques,
> deuxième Série, tomé XXVIII):
>
> " .... Pour un observateur, entraîné lui-même dans une translation dont il
> ne se doute pas, aucune vitesse apparente ne pourrait non plus dépasser
> celle de la lumière; et ce serait là une contradiction, si l'on ne se
> rappelait que cet observateur ne se servirait pas des mêmes horloges qu'un
> observateur fixe, mais bien d'horloges marquant le "temps local". "

That's a nice one, but it doesn't show that he understood that this local
time implies a different rate.

Harald

Martin Ouwehand

unread,
Sep 27, 2005, 3:37:28 PM9/27/05
to
In article <43328457$1...@epflnews.epfl.ch>, I wrote:

] I understand from his arguments around pages 565-566


] that he uses the following transformation:
]
] x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz contraction)
] t' = t - (v * x) / (c^2 - v^2) ("local time")

I made a mistake (it should be x-vt in the equation for t'), the full
transformation between ether frame (unprimed [x, y, t]) and moving frame
(primed [x', y', t']) is:

x' = (x - vt) / sqrt(1 - v^2/c^2)
y' = y
t' = t - ((v * (x - vt)) / (c^2 - v^2))
= (t - vx/c^2) / (1 - v^2/c^2)

Let me show how this is consistent with what Poincaré says on pages 565-566
of the article http://www.soso.ch/wissen/hist/SRT/P-1908.pdf. He considers
two events: A (emission of a light wave) and B (detection of the light
on an arbitrary point of the wave front at some later time). Let the
space-time coordinates of A and B in the ether frame be:

x_A = 0
y_A = 0
t_A = 0
and
x_B = ct cos(a)
y_B = ct sin(a)
t_B = t

(the angle a is arbitrary and serves as parameter to denote any point on
the wave front.)

With the help of the above formulas, I find that the space-time coordinates
in the moving frame are:

x_A' = 0
y_A' = 0
t_A' = 0
and
x_B' = (ct cos(a) - vt) / sqrt(1 - v^2/c^2)
y_B' = ct sin(a)
t_B' = (t - (vct cos(a) /c^2)) / (1 - v^2/c^2)

Then I can check that the circular (in the ether frame) wave front goes into
an ellipse

(x_B' * sqrt(1 - v^2/c^2) + vt)^2 + y_B'^2 = (ct)^2

with ellipcity e = v/c and center [-vt * sqrt(1 - v^2/c^2), 0], corresponding
to the picture on page 566.

Next I compute Poincaré's AB and AB':

AB = sqrt(x_B'^2 + y_B'^2) = t * (c - v * cos(a)) / sqrt(1 - v^2/c^2)
AB' = x_B' = t * (c cos(a) - v)/ sqrt(1 - v^2/c^2)

and check that indeed:

AB + v/c * AB' = ct * sqrt(1 - v^2/c^2)

which is the second equation on page 566. Then I can find the next-to-last
equation for the local time by rewriting:

tau = t_B'
= (t - (vct cos(a)/c^2)) / (1 - v^2/c^2)
= (t - t* v^2/c^2 + t * v^2/c^2 - (vct cos(a)/c^2))/(1 - v^2/c^2)
= t - ((ct cos(a) - vt)*v/c^2)/(1 - v^2/c^2)
= t - ((AB' v/c) / c sqrt(1 - v^2/c^2))

Finally, it's easy to check that:

AB = c tau sqrt(1 - v^2/c^2)

which is the last equation (with t corrected to tau -- that this is
a misprint can be seen by comparing the next-to-last and the second
equation).

As AB is the distance travelled by the ligth wave and tau the time of
travel, *as measured by an observer in the moving frame*, I deduce that
the speed of light for that observer is:

c' = AB / tau = c sqrt(1 - v^2/c^2)

While it is true that "you don't find such a nonsense" (as Homo Lykos
says) in the article, it's just a division away :-/

Now I'd like to follow-up to some remarks by Harry and Homo Lykos.

In article <43328457$1...@epflnews.epfl.ch>,
Harry <harald.v...@epfl.ch> writes:

] > you seem to be saying that after discovering Special Relativity in 1905,


] > he changed his mind... It is easy to see that what is missing in his 1908
] > article is time dilatation:
]
] I am flabbergasted - "time dilatation" is represented by the tau on page
] 566.

there is "time delay" but no time dilatation in the equation linking t and
tau: for an observer at rest in the moving frame (hence: constant AB')
a phenomenon won't start at the same time as for an observer in the ether
frame (because of the second term -- that's time delay), but its *duration*
will be the same (t and tau come with the same unit factor in the equation.)
Hence, in Poincaré's theory time durations have an absolute meaning.
Not so in Einstein's theory.

In article <4335d73e$1...@news.bluewin.ch>,
Homo Lykos <ly...@lykos.ch> writes:

] Especially strange for me:


]
] " Supposons que la différence entre le temps vrai et le temp local en un
] point quelconque soit égale à l'abscisse de ce point multipliée par la
] constante: e/(V sqrt(1-e^2)) "
]
] Poincaré gives no explanation for this (and speaks only of supposons(=we
] suppose)) and I - at least in this moment - can't understand it.

if you compute in the ether frame the correction needed to synchronize
moving clocks, you get a term vL/(c^2 - v^2) where L is the distance
between the clocks projected on the direction of the motion measured
in the ether frame -- you get Poincaré's expression if you use the distance
as measured in the moving frame but corrected for the length contraction.

Note that Einstein uses the same synchronisation procedure as Poincaré
(who must indeed be credited for this nice idea) but comes to different
conclusions because he postulates that the speed of light is the same in all
inertial frames.

--
| ~~~~~~~~ Martin Ouwehand ~ Swiss Federal Institute of Technology ~ Lausanne
__|_____________ Email/PGP: http://slwww.epfl.ch/info/Martin.html _____________

The right question to ask is sometimes better
than the right answer to the wrong question [Clifford Truesdell]

Homo Lykos

unread,
Sep 28, 2005, 10:15:51 PM9/28/05
to
"Martin Ouwehand" <see...@end.of.post.ch> schrieb im Newsbeitrag
news:4337fbc2$1...@epflnews.epfl.ch...

>
> Let me show how this is consistent with what Poincaré says on pages
> 565-566
> of the article http://www.soso.ch/wissen/hist/SRT/P-1908.pdf. He considers
> two events: A (emission of a light wave) and B (detection of the light
> on an arbitrary point of the wave front at some later time).
.....

>
> Finally, it's easy to check that:
>
> AB = c tau sqrt(1 - v^2/c^2)
>
> which is the last equation (with t corrected to tau -- that this is a
> misprint

This is no misprint, but Poincarés mistake in his "popular proof" of
Michelson-Morley, as one can see by comparison with the text, what I did in
an other note. So he was incorrectly thinking that his assumption (supposons
..) would be a good one without controlling all this a second time or
carefully enough.


Homo Lykos


Harry

unread,
Sep 28, 2005, 10:15:52 PM9/28/05
to
Continuing discussion of :
http://www.soso.ch/wissen/hist/SRT/P-1908.pdf

"Martin Ouwehand" <see...@end.of.post.ch> wrote in message

news:4337fbc2$1...@epflnews.epfl.ch...


> In article <43328457$1...@epflnews.epfl.ch>, I wrote:
>
> ] I understand from his arguments around pages 565-566
> ] that he uses the following transformation:
> ]
> ] x' = (x - v * t) / sqrt(1 - v^2/c^2) (Lorentz
contraction)
> ] t' = t - (v * x) / (c^2 - v^2) ("local time")
>
> I made a mistake (it should be x-vt in the equation for t'), the full
> transformation between ether frame (unprimed [x, y, t]) and moving frame
> (primed [x', y', t']) is:
>
> x' = (x - vt) / sqrt(1 - v^2/c^2)
> y' = y
> t' = t - ((v * (x - vt)) / (c^2 - v^2))
> = (t - vx/c^2) / (1 - v^2/c^2)

Dear Martin, Poincare certainly didn't abandon the Lorentz transformations.

And pasting here what you concluded with:

> Note that Einstein uses the same synchronisation procedure as
> Poincaré (who must indeed be credited for this nice idea) but
> comes to different conclusions because he postulates that the
> speed of light is the same in all inertial frames.

Note also that Einstein postulated what Poincare had concluded, so that they
could not disagree about that.

According to Poincare, the full transformation between the measured values
in any moving inertial frame and in the ether frame as well as between those
in any set of inertial frames is:

x' = (x + vt) / sqrt(1 - v^2/V^2)
y' = y
z' = z
t' = (t + vx/V^2) / sqrt(1 - v^2/V^2)

The sign depends on the choice of which coordinates one chooses as the
primed ones.
Thus, according to your interpretation, there is an error in the time
calculation of his M-M example. Logically, any interpretation of
explanations by Poincare in the context of Lorentz' theory that disagrees
with the LT must be either due to an interpretation error or an error in the
text.

In order to not contradict his Lorentz transformation, tau must be equal to
t*sqrt(1-v^2/V^2), so that he had to end with the last equation just as it
appeared in print (BTW, I misread that the first time):

AB = V*t*sqrt(1-v^2/V^2)

>From that he concluded that Michelson's experiment will yield an *apparent
transmission duration* that is proportional to the apparent distance
(independent of the angle).

I'll now follow you and also have a closer look at it, to try to spot where
the error is. See below.

> Let me show how this is consistent with what Poincaré says on pages
565-566
> of the article http://www.soso.ch/wissen/hist/SRT/P-1908.pdf. He considers
> two events: A (emission of a light wave) and B (detection of the light
> on an arbitrary point of the wave front at some later time).

I read: the light goes "de B en A", which I think can only mean from B to
A.

Also, I had some difficulty with:

"We choose the contraction law, such that the point S is at the base of the
meridian section of the ellipse."

It's in cursive, thus important.
I think that he meant that we shift the local time such that the contraction
ellipse is apparently centered around the source.
Then, the detector A is located at the source S, and we look at the light
that returns from the apparent position of B back to A.

Note that this apparent position is due to length contraction and time
offset, while still using absolute time.
Apparently, he wanted to illustrate local time measurement by at first not
accounting for it - IMO a bit cumbersome, but typical for him. As he stated:

"How will we then proceed, to evaluate the time that the light takes to go
from B to A?"

Thus IMO he does not, at that point, use his Lorentz transformations, but
instead he illustrates the consequences for local time measurement, taking
the well-known assumption of length contraction for granted.

IOW, fig.2 sketches only half of the Lorentz transformation, as he uses
local (apparent) coordinates A and B with the true duration t (watch out:
this "t" is *not* a time coordinate; it corresponds to duration delta_t of
the Lorentz transformations!).

That is confirmed by his second equation on p.566:

AB + v/V *AB' = V*t*sqrt(1-v^2/c^2)

You overlooked that that would not only contradict everything he said before
but even his conclusion in the next paragraph.

Now I'll do a first attempt to finish following Poincare's reasoning,
instead of yours:

The direction of motion is along PP'.
His first equation is trigonometry with v/V=e, the excentricity.

Next he states that, as there is no effect on lateral dimensions,

OQ = Vt

I first didn't spot his mistake, but here it happened!
Ironically, it's the same mistake that Michelson made in 1881 and that
Lorentz corrected before Michelson repeated it with Morley.
He should have stated:

OQ = Vt *sqrt(1-v^2/V^2)

Overlooking that, follows his second equation,

AB + e *AB' = V*t*sqrt(1-v^2/V^2)

with AB' = x'_B - x'_A
(x' = moving frame coordinates)

It should have been:

AB + e *AB' = V*t*(1-v^2/V^2)

He states in words (no symbols, so I generate them here but it's
inconvenient as the symbol t is already taken, leading to confusing
notation - which is no doubt why he skipped it):

Supposing that the difference between true and local time at a point in time
and space depends on the location of the clock along PP' as well as on a
constant that is a function of the speed, as follows:

tau_p - t_p = x'_p * C

With tau_p and t_p indicating instances,
and C = e/(V*sqrt(1-v^2/V^2))

(Note: here I corrected what looks like sloppy phrasing, as from his words I
first guessed that he meant "t_p - tau_p", but then the sign doesn't come
out right. Thus that would be a little glitch on his part.)

>From that the apparent duration of the transmission from B to A is as
follows:

tau_A - t_A = x'_A * C
tau_B - t_B = x'_B * C
-------------------------- -
tau_A - tau_B - t_A + t_B = (x'_A - x'_B) * C

tau_A - tau_B = t_A - t_B + (x'_A - x'_B ) * C

So that, going back to his notation,

tau = t - AB' * C

He next claims that from that follows that :

AB = V*t*sqrt(1-v^2/V^2)

However, this is in direct contradiction with his second equation, due to
his mistake in that second equation.
Perhaps he was so sure that it would work out (as he knew that it should),
that he didn't bother to verify it.

Concistency check (I won't bother to derive it):

Taking the correct equations and writing g for 1/sqrt(1-v^2/c^2),

AB + e *AB' = V*t/g^2 }
t = tau + e* AB' /(V/g) }

AB + e *AB' = V*t/g^2 }
t *(V/g) = tau*(V/g) + e*AB' }
----------------------------------- -
AB - t *(V/g) = V*t/g^2 - tau * (V/g)

With tau = t/g we get:

AB - t *(V/g) = V*t/g^2 - t/g * (V/g)
AB - t *(V/g) = 0

So that indeed:

AB = V* t/g = V*tau

Which is what he attempted to show.

<