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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

Sep 5, 2005, 2:12:40 PM9/5/05

to

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.

> 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

Sep 5, 2005, 3:30:40 PM9/5/05

to

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.

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

Sep 5, 2005, 8:00:53 PM9/5/05

to

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.

> 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

Sep 6, 2005, 10:59:16 AM9/6/05

to

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.

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

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.

http://www.arxiv.org/abs/quant-ph/9609002 . This paper is quite

interesting in other respects, too.

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

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.

<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

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?

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

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.

[...]

> 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.

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.

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.

>

founder of sr, they should look at what Rovelli says.

Regards

--

Charles Francis

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?

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.

>

>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

>

>

Regards

--

Charles Francis

Sep 7, 2005, 7:28:42 PM9/7/05

to

"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

Sep 7, 2005, 7:28:52 PM9/7/05

to

"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

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

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 :

"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

+++

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...

>>

>

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.

> 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

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?

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)

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

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...

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

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

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

Sep 12, 2005, 10:48:35 PM9/12/05

to

In article <1126187763.9...@g44g2000cwa.googlegroups.com>,

"Juan R." <juanrgo...@canonicalscience.com> writes:

"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]

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

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

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

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.

> 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?

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

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'.

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

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

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

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

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’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

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

to

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.

> 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

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

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

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

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

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

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’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

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

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=> 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

nt

> > is not spherical in x' because in Einstein 1905 words:

> >

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)

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

to

news:1127031732.8...@g47g2000cwa.googlegroups.com...

> Homo Lykos wrote:

SNIP

> 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

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.

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

Sep 21, 2005, 4:54:14 PM9/21/05

to

In article <1126626847.8...@g43g2000cwa.googlegroups.com>,

"Juan R." <juanrgo...@canonicalscience.com> writes:

"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]

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

to

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,

> 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

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[...]"

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

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

Sep 27, 2005, 3:37:21 PM9/27/05

to

"Homo Lykos" <ly...@lykos.ch> wrote in message

news:4335d73e$1...@news.bluewin.ch...

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

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]

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).

.....

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

Sep 28, 2005, 10:15:52 PM9/28/05

to

Continuing discussion of :

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

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.

<