J. B. Wood ha scritto:

... Maxwell gets the glory for tying together experiments
performed by Faraday, Gauss, Ampere, Oersted et al. And not to forget the
mathematicians who labored to provide the framework. The point here is
that an individual such as Maxwell or Einstein (who most certainly built
upon the work of Maxwell) tied together the seemingly disparate
observations of others.

I would hardlly qualify Poincare's theory as a set of "seemingly
disparate observations". Personally, I consider Einstein's contribution
to SR conceptually decisive, but I don't see how Poincare's previous
SR work can be regarded otherwise than as fundamental.

A good treatment of the issue is Darrigal's essay ([1]). The paragraph
"Similarities and Differences" is illuminating, as it pinpoints the
originality of Einstein's arguments. Also the timeline at the end of
the paper is very useful.

By the way, Einstein may indeed have been cavalier in (not)
acknowledging other people's contributions, but it's a fact that his
overall approach worked, far beyond SR. I am not sure that his key 1905
SR paper would have had the same impact if he had started it with the
words "We will present here a reinterpretation of Poincare's and
Lorentz's recent work". Einstein's mix of vision, expediency and
rigour shaped modern physics as we know it.

IV

[1] http://www.univ-nancy2.fr/DepPhilo/w...p/DarO2004.pdf

I.Vecchi wrote:

Anyways, there is a good and very recent artcle by Tony Rothman
available online:
"Lost in Einstein's Shadow . Einstein gets the glory, but others
were paving the way" at

http://www.americanscientist.org/tem...baa53KLv5HQuI_

I'm not too impressed by what he says about Poincaré's article,
for instance that because he sets the speed of light c = 1,
at the start, he fails to see the importance of the speed of light
being
the same to all inertial observers.

I don't think that Poincaré ever understood this, as well as
time dilatation, as can be seen in his 1908 article "La dynamique
de l'électron" (not the same as th 1906 one), on pages 565-566:

http://www.soso.ch/wissen/hist/SRT/P-1908.pdf

see my posting of last year:


http://groups.google.com/group/sci.p...8e6bcc7eb9383e

"Murray Arnow" schrieb
Most people who detract from Einstein make the error that SR and Lorentz
transformations are identical. SR is a theory based on two simple
postulates, which no one until Einstein realized their significance.

New sets of postulates are not that much important.

The theory of natural numbers has existed long before Peanos
axioms. And a really complete set of axioms for geometry
has been found only a long time after Euclid.

And I see nothing important for the future development
of physics which was not present in Poicare's paper in
comparison to Einstein's.

De Broglie relied heavily on SR for his theory.

And was, therefore, less successful than the QM founders.

You can still continue being an Einstein fan.

Of course. There is far too much he has done beyond
that SR paper. The other 1905 papers, GR, the EPR
paper.

Ilja

schrieb:
I.Vecchi wrote:

Anyways, there is a good and very recent artcle by Tony Rothman
available online:
"Lost in Einstein's Shadow . Einstein gets the glory, but others
were paving the way" at

http://www.americanscientist.org/tem...baa53KLv5HQuI_

I'm not too impressed by what he says about Poincaré's article,
for instance that because he sets the speed of light c = 1,
at the start, he fails to see the importance of the speed of light
being the same to all inertial observers.

I don't think that Poincaré ever understood this, as well as
time dilatation, as can be seen in his 1908 article "La dynamique
de l'électron" (not the same as th 1906 one), on pages 565-566:

http://www.soso.ch/wissen/hist/SRT/P-1908.pdf

see my posting of last year:


http://groups.google.com/group/sci.p...8e6bcc7eb9383e

You have forgotten to cite the answers of the next days of harry and myself
to this nonsens. From these answers anybody can see, that you have only
found an error done by Poincaré in this paper - more exactly 2 errors, a
physical and a writing one interfering with each other - without
recognizing, that it was only an error:

Ex falso quod libet.

More about the history of the special theory of relativity with important
original papers you find in:

http://www.soso.ch/wissen/hist/SRT/srt.htm

The most important references are [L1], [P2] and [P3]


Homo Lykos

"Murray Arnow" schrieb
Ilja Schmelzer wrote:
Murray Arnow schrieb
Most people who detract from Einstein make the error that SR and
Lorentz
transformations are identical. SR is a theory based on two simple
postulates, which no one until Einstein realized their significance.

New sets of postulates are not that much important.

The theory of natural numbers has existed long before Peanos
axioms. And a really complete set of axioms for geometry
has been found only a long time after Euclid.

And I see nothing important for the future development
of physics which was not present in Poicare's paper in
comparison to Einstein's.


This seems to be a misunderstanding that shows up occasionally in this ng.
I wish to make this statement as emphatically a I can: physics is not
mathematics.

Writing down and solving equations is not as important as understanding
what the equations *mean*. What Einstein provided was a *physical*
understanding of SR.

The physical meaning was not different: There is full agreement
about what can be measured, how, and what the theory
predicts for these measurements.

The Einstein-Minkowski spacetime interpretation is an
interpretation, it should be distinguished from the
physical meaning of the theory.

De Broglie relied heavily on SR for his theory.

And was, therefore, less successful than the QM founders.

He was?

The theory of Schrödinger and Heisenberg was non-relativistic.
The same for Bohmian mechanics.

The unification of GR and QM is still an open problem.

Ilja

wrote:

I'm not too impressed by what he says about Poincaré's article,
for instance that because he sets the speed of light c = 1,
at the start, he fails to see the importance of the speed of light
being
the same to all inertial observers.

I don't think that Poincaré ever understood this, as well as
time dilatation, as can be seen in his 1908 article "La dynamique
de l'électron" (not the same as th 1906 one), on pages 565-566:

Indeed not. Poincare may have been mere steps away, but they were big
steps, and he missed it. Likewise, Klein had some years earlier
published his work on the spinning top, in which he uses a
non-Euclidean (affine) geometry based on a projective metric built on
the fundamental quadric

x^2 + y^2 + z^2 - t^2 = 0

He goes to some lengths to caution the reader about imputing any
metaphysical reality to this quadric and the associated metric. In fact
it is the light cone, and as real as rain. He missed it by a hair, but
a hair may as well have been a light year in this case. Poincare misses
relativity at least as many hairs. This is a case of "getting it right"
- Klein and Poincare, the premiere mathematicians of the day, missed it
(as did Hilbert later) - Einstein, the physicist, got it right.

I am heartily sick of Einstein-bashing. Let the mathematicians eat
cake.

-drl

Ilja Schmelzer wrote:

The physical meaning was not different: There is full agreement
about what can be measured, how, and what the theory
predicts for these measurements.

The Einstein-Minkowski spacetime interpretation is an
interpretation, it should be distinguished from the
physical meaning of the theory.

The concept of spacetime is essential, because the theory is really one
of invariants built there.

-drl

"Murray Arnow" wrote in message
t...
Ilja Schmelzer wrote:

Murray Arnow schrieb

What Einstein provided was a *physical* understanding of SR.

[regarding Poincare]
The physical meaning was not different: There is full agreement
about what can be measured, how, and what the theory
predicts for these measurements.


I don't believe this is correct. Physical measurements require special
attention to simultaneity. Einstein showed how to do this. It is this
detail
regarding time that accounts for, among other things, the Lorentz
contraction.

If I'm not mistaken, it was already mentioned in the before-mentioned thread
that Poincare showed how to do this before Einstein. Please pay also
attention to the difference between accounting and understanding of what is
really going on, physically...

As far as full agreement about predictions is concerned, do the pre-SR
theories give all of SR's predictions? Can you do without SR to
correctly understand the physics of the pre-SR predictions?

It depends on what you mean with "pre-SR". With Lorentz-1904 and
Poincare-1905 (which was published before Einstein-1905 was submitted for
review) SR was basically established. Einstein-1905 provides a nice overview
with useful additions, and so does Poincare-1906 which is the extended
version of his 1905 note.

The Einstein-Minkowski spacetime interpretation is an
interpretation, it should be distinguished from the
physical meaning of the theory.

How do you do that?

It's the physical model of your choice that explains your physical
interpretation - just as in QM.

Harald