http://helios.gsfc.nasa.gov/qa_sp_gr.html
"Is light affected by gravity? If so, how can the speed of light be
constant? Wouldn't the light coming off of the Sun be slower than the
light we make here? If not, why doesn't light escape a black hole?
Yes, light is affected by gravity, but not in its speed. General
Relativity (our best guess as to how the Universe works) gives two
effects of gravity on light. It can bend light (which includes effects
such as gravitational lensing), and it can change the energy of light.
But it changes the energy by shifting the frequency of the light
(gravitational redshift) not by changing light speed. Gravity bends
light by warping space so that what the light beam sees as "straight"
is not straight to an outside observer. The speed of light is still
constant." Dr. Eric Christian

Pentcho Valev

On 8 Aug, 09:15, Pentcho Valev wrote:
http://helios.gsfc.nasa.gov/qa_sp_gr.html
"Is light affected by gravity? If so, how can the speed of light be
constant? Wouldn't the light coming off of the Sun be slower than the
light we make here? If not, why doesn't light escape a black hole?
Yes, light is affected by gravity, but not in its speed. General
Relativity (our best guess as to how the Universe works) gives two
effects of gravity on light. It can bend light (which includes effects
such as gravitational lensing), and it can change the energy of light.
But it changes the energy by shifting the frequency of the light
(gravitational redshift) not by changing light speed. Gravity bends
light by warping space so that what the light beam sees as "straight"
is not straight to an outside observer. The speed of light is still
constant." Dr. Eric Christian

A more developed explanation of the constancy/variability of the speed
of light in a gravitational field that makes bellicose zombies in
Einstein criminal cult go into convulsions, sing "Divine Einstein" and
look for heretics to destroy:

http://math.ucr.edu/home/baez/physic..._of_light.html
Sreve 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 and general 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. The problem here comes from the fact that speed is a
coordinate-dependent quantity, and is therefore somewhat ambiguous.
To determine speed (distance moved/time taken) you must first choose
some standards of distance and time, and different choices can give
different answers. This is already true in special relativity: IF YOU
MEASURE THE SPEED OF LIGHT IN AN ACCELERATED REFERENCE FRAME, THE
ANSWER WILL, IN GENERAL, DIFFER FROM c. In special relativity, the
speed of light is constant when measured in any inertial frame. In
general relativity, the appropriate generalisation is that the speed
of light is constant in any freely falling reference frame (in a
region small enough that tidal effects can be neglected). In this
passage, Einstein is not talking about a freely falling frame, but
rather about a frame at rest relative to a source of gravity. IN SUCH
A FRAME, THE SPEED OF LIGHT CAN DIFFER FROM c, basically because of
the effect of gravity (spacetime curvature) on clocks and rulers."

Pentcho Valev

Et si t'allais faire du sport au lieu de nous faire chier ?

Pentcho Valev a écrit :
un gros tas de conneries.


--
C'est Ã* l'heure du repas
qu'on voit les boules du chat