On Mar 27, 10:33 am, critico
> On 16 mar, 20:22, BradGuth
>
>
>
> > On Mar 11, 11:21 pm, Pentcho Valev
>
> > > On Mar 11, 5:27 am, Tom Roberts
> > > sci.physics:
>
> > > > Tom wrote:
> > > > > The speed of light varies depending on the strength of the
> > > > > gravitational field. Einstein said that.
>
> > > > He said that in 1911, early on the then-unfinished journey to Genera=
l
> > > > Relativity. GR itself does not really have this property -- the _LOC=
AL_
> > > > speed of light is everywhere c. When measured over non-local paths t=
he
> > > > speed of light can vary, but there is no definite dependence on
> > > > "strength of the gravitational field", it's rather that one must com=
pute
> > > > an integral over the path to obtain the theoretical value for such a=
> > > > speed measurement.
>
> > > > Yes, as one prolific idiot around here is fixated on,
> > > > in the APPROXIMATION of weak fields and restriction to
> > > > paths at fixed gravitational potential, for Newtonian
> > > > coordinates one can express the non-local COORDINATE
> > > > speed of light in terms of the gravitational potential.
> > > > In 1911 Einstein did not understand all the caveats
> > > > mentioned here, but certainly did by 1915; this idiot
> > > > still does not understand them.
>
> > > The year is 1920 Roberts Roberts and Divine Albert still believes that=
> > > the speed of light "varies with position" in a gravitational field, as=
> > > Superior Brother Steve Carlip explains to you:
>
> > >http://math.ucr.edu/home/baez/physics/Relativity/SpeedOfLight/speed_o..=
.
> > > Superior Brother Steve Carlip: "Einstein went on to discover a more
> > > general theory of relativity which explained gravity in terms of
> > > curved spacetime, and he talked about the speed of light changing in
> > > this new theory. In the 1920 book "Relativity: the special andgeneral=
theory" he wrote: ". . . 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 [. . .] 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." Since
> > > Einstein talks of velocity (a vector quantity: speed with direction)
> > > rather than speed alone, it is not clear that he meant the speed will
> > > change, but the reference to special relativity suggests that he did
> > > mean so. THIS INTERPRETATION IS PERFECTLY VALID AND MAKES GOOD
> > > PHYSICAL SENSE, but a more modern interpretation is that the speed of
> > > light is constant in general relativity."
>
> > > In a sense, Superior Brother Steve Carlip is less dishonest (or more
> > > naive) than you Roberts Roberts.
>
> > > Pentcho Valev
> > > pva...@yahoo.com
>
> > Interesting, but why does light reflect off a mirror, or get refracted
> > by an atmosphere?
>
> > Perhaps photons do not actually bend, but merely interact with other
> > matter, be it regular or dark matter.
> > . - Brad Guth-
>
> Bravo les artistes ! 57 interventions et pas un mot en Fran=E7ais .
> On est bien sur un groupe fr. n'est-ce pas ?
> Alors, pour ceux qui ne ma=EEtrisent pas l'englich, il est tr=E8s
> difficile de rep=E9rer les conneries, car il doit y en avoir un tas , of
> course...
> Sans rancune, mais avec un pointe d'mamertume.
?
Primary photons are not the same as secondary photons, and so forth.
=2E - Brad Guth