On Feb 6, 5:33*pm, wrote:
On 6 fév, 02:34, Pentcho Valev wrote:
http://philipball.blogspot.com/2007/...-was-innocent-...
"With the technology then available, measuring the bending of
starlight was very challenging. And contrary to popular belief,
Newtonian physics did not predict that light would remain undeflected
- Einstein himself pointed out in 1911 that Newtonian gravity should
cause some deviation too. So the matter was not that of an all-or-
nothing shift in stars' positions, but hinged on the exact numbers."
Right.
Classical Newtonian mechanics predicts that light will bend with
twice the angle observed.
Relativistic Newtonian mechanics however predicts the correct
angle since it is now understood that only half a photon's energy
is sensitive to transverse interaction.
If you wish your analysis to be complete, you should discuss
Einstein's 1911 equation c'=c(1+V/c^2) showing how the speed of light
varies with the gravitational potential V. Note that c'=c(1+V/c^2) is
consistent with the gravitational redshift factor 1+V/c^2 confirmed
experimentally:
http://www.blazelabs.com/f-g-gcont.asp "The first confirmation of a
long range variation in the speed of light travelling in space came in
1964. Irwin Shapiro, it seems, was the first to make use of a
previously forgotten facet of general relativity theory -- that the
speed of light is reduced when it passes through a gravitational
field....Faced with this evidence, Einstein stated:"In the second
place our result shows that, according to the general theory of
relativity, the law of the constancy of the velocity of light in
vacuo, which constitutes one of the two fundamental assumptions in the
special theory of relativity and to which we have already frequently
referred, cannot claim any unlimited validity. A curvature of rays of
light can only take place when the velocity of propagation of light
varies with position."......Today we find that since the Special
Theory of Relativity unfortunately became part of the so called
mainstream science, it is considered a sacrilege to even suggest that
the speed of light be anything other than a constant. This is somewhat
surprising since even Einstein himself suggested in a paper "On the
Influence of Gravitation on the Propagation of Light," Annalen der
Physik, 35, 1911, that the speed of light might vary with the
gravitational potential. Indeed, the variation of the speed of light
in a vacuum or space is explicitly shown in Einstein's calculation for
the angle at which light should bend upon the influence of gravity.
One can find his calculation in his paper. The result is c'=c(1+V/c^2)
where V is the gravitational potential relative to the point where the
measurement is taken. 1+V/c^2 is also known as the GRAVITATIONAL
REDSHIFT FACTOR."
Note also that, by applying Einstein's equivalence principle, you can
prove that c'=c(1+V/c^2) is equivalent to c'=c+v, an equation given by
Newton's emission theory and showing how the speed of light varies
with v, the relative speed of the light source and the observer, in
the absence of a gravitational field.
Pentcho Valev
However Budding Young Einsteins are taught in a different way:
http://pirsa.org/speaker/Lee_Smolin
Lee Smolin - ISSYP Keynote Session
Speaker(s): Lee Smolin
Abstract:
Date: 01/08/2007 - 1:00 pm
http://streamer.perimeterinstitute.c...?peid=5f32739a....
Lee Smolin: "Newton's theory predicts that light goes in straight
lines and therefore if the star passes behind the sun, we can't see
it. Einstein's theory predicts that light is bent...."
Pentcho Valev
Agreed. Outright falsehood. Probably plain ignorance on the part
of this author.
André Michaud