Why Einstein Proposed That Speed Of Light Is Invariable....

On May 13, 5:19*am, Tom Roberts wrote in
sci.physics.rlativity:
xxein wrote:
Source independency does not confer any other
attribute to light except the ability to function apart from the
source.

Hmm. That plus the PoR implies that the vacuum speed of light is
invariant (i.e. has the value c in any inertial frame). It is rather
silly to separate one statement from a theory and attempt to interpret
it apart from the rest of the theory....

As for any physical theory (which is a collection of mathematical
theorems and the interpretations of their symbols), one has many choices
for the set of equations one takes as postulates. Einstein selected his
postulates to accord with then-current theoretical expectations and
prejudices.

Today we can select a rather different set of postulates that completely
avoids criticisms about "assuming the speed of light is constant":
* 1) the PoR
* 2) pion beams exist
These are sufficient to derive all of SR, when combined with:
* * ** the definition of inertial frames
* * ** Einstein's "hidden postulates"
* * * * - clocks and rulers have no memory
* * * * - space is isotropic and homogeneous
* * * * - time is homogeneous and monotonic
* * ** knowledge of what a pion is.
Einstein, of course, had no access to the last of these, nor sufficient
knowledge of group theory to apply them properly.

* * * * Indeed, SR became the first major application of group
* * * * theory in theoretical physics, first as a transformation
* * * * group (Lorentz invariance), and then as angular momentum
* * * * in non-relativistic quantum mechanics (!), and ultimately
* * * * in QED and other QFTs.

Today, with knowledge gained from GR, we can see the limitations of
inertial frames and the PoR. This relegates SR to being merely a LOCAL
theory.

Tom Roberts

Always devising new camouflage Roberts Roberts? Why do Einsteinians
need "a rather different set of postulates that completely avoids
criticisms about "assuming the speed of light is constant"? Are they
afraid of something? Old camouflage:

http://groups.google.com/group/sci.p...b971595bf0fe4?

If I were you Roberts Roberts, I would immediately adopt the
"different set of postulates" that Brother Jean Eisenstaedt offers:

http://ustl1.univ-lille1.fr/culture/...40/pgs/4_5.pdf
Jean Eisenstaedt: "Il n'y a alors aucune raison théorique à ce que la
vitesse de la lumière ne dépende pas de la vitesse de sa source ainsi
que de celle de l'observateur terrestre ; plus clairement encore, il
n'y a pas de raison, dans le cadre de la logique des Principia de
Newton, pour que la lumière se comporte autrement - quant à sa
trajectoire - qu'une particule matérielle. Il n'y a pas non plus de
raison pour que la lumière ne soit pas sensible à la gravitation.
Bref, pourquoi ne pas appliquer à la lumière toute la théorie
newtonienne ? C'est en fait ce que font plusieurs astronomes,
opticiens, philosophes de la nature à la fin du XVIIIème siècle. Les
résultats sont étonnants... et aujourd'hui nouveaux."
IN ENGLISH: "Therefore there is no theoretical reason why the speed of
light should not depend on the speed of the source and the speed of
the terrestrial observer as well; even more clearly, there is no
reason, in the framework of the logic of Newton's Principia, why light
should behave, as far as its trajectory is concerned, differently from
a material particle. Neither is there any reason why light should not
be sensible to gravitation. Briefly, why don't we apply the whole
Newtonian theory to light? In fact, that is what many astronomers,
opticians, philosophers of nature did by the end of 18th century. The
results are surprising....and new nowadays."

Pentcho Valev

The ISM is what it is, a dark medium in which the speed of a photon is
limited to something less than 300,000 km/s.

Get past the local ISM of dark matter and the photon race is on.
Possibly 1,000,000 km/s.
. - Brad Guth


Pentcho Valev wrote:
On May 13, 5:19�am, Tom Roberts wrote in
sci.physics.rlativity:
xxein wrote:
Source independency does not confer any other
attribute to light except the ability to function apart from the
source.

Hmm. That plus the PoR implies that the vacuum speed of light is
invariant (i.e. has the value c in any inertial frame). It is rather
silly to separate one statement from a theory and attempt to interpret
it apart from the rest of the theory....

As for any physical theory (which is a collection of mathematical
theorems and the interpretations of their symbols), one has many choices
for the set of equations one takes as postulates. Einstein selected his
postulates to accord with then-current theoretical expectations and
prejudices.

Today we can select a rather different set of postulates that completely
avoids criticisms about "assuming the speed of light is constant":
� 1) the PoR
� 2) pion beams exist
These are sufficient to derive all of SR, when combined with:
� � �* the definition of inertial frames
� � �* Einstein's "hidden postulates"
� � � � - clocks and rulers have no memory
� � � � - space is isotropic and homogeneous
� � � � - time is homogeneous and monotonic
� � �* knowledge of what a pion is.
Einstein, of course, had no access to the last of these, nor sufficient
knowledge of group theory to apply them properly.

� � � � Indeed, SR became the first major application of group
� � � � theory in theoretical physics, first as a transformation
� � � � group (Lorentz invariance), and then as angular momentum
� � � � in non-relativistic quantum mechanics (!), and ultimately
� � � � in QED and other QFTs.

Today, with knowledge gained from GR, we can see the limitations of
inertial frames and the PoR. This relegates SR to being merely a LOCAL
theory.

Tom Roberts

Always devising new camouflage Roberts Roberts? Why do Einsteinians
need "a rather different set of postulates that completely avoids
criticisms about "assuming the speed of light is constant"? Are they
afraid of something? Old camouflage:

http://groups.google.com/group/sci.p...b971595bf0fe4?

If I were you Roberts Roberts, I would immediately adopt the
"different set of postulates" that Brother Jean Eisenstaedt offers:

http://ustl1.univ-lille1.fr/culture/...40/pgs/4_5.pdf
Jean Eisenstaedt: "Il n'y a alors aucune raison th�orique � ce que la
vitesse de la lumi�re ne d�pende pas de la vitesse de sa source ainsi
que de celle de l'observateur terrestre ; plus clairement encore, il
n'y a pas de raison, dans le cadre de la logique des Principia de
Newton, pour que la lumi�re se comporte autrement - quant � sa
trajectoire - qu'une particule mat�rielle. Il n'y a pas non plus de
raison pour que la lumi�re ne soit pas sensible � la gravitation.
Bref, pourquoi ne pas appliquer � la lumi�re toute la th�orie
newtonienne ? C'est en fait ce que font plusieurs astronomes,
opticiens, philosophes de la nature � la fin du XVIII�me si�cle. Les
r�sultats sont �tonnants... et aujourd'hui nouveaux."
IN ENGLISH: "Therefore there is no theoretical reason why the speed of
light should not depend on the speed of the source and the speed of
the terrestrial observer as well; even more clearly, there is no
reason, in the framework of the logic of Newton's Principia, why light
should behave, as far as its trajectory is concerned, differently from
a material particle. Neither is there any reason why light should not
be sensible to gravitation. Briefly, why don't we apply the whole
Newtonian theory to light? In fact, that is what many astronomers,
opticians, philosophers of nature did by the end of 18th century. The
results are surprising....and new nowadays."

Pentcho Valev