Pentcho Valev
In his 1920 "Relativity" Einstein declares that, in a gravitational field, the speed of light "varies with position" and today's hypnotists in Einstein criminal cult find that this declaration "is perfectly valid and makes good physical sense":

http://www.math.ucr.edu/home/baez/physics/...d_of_light.html
"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."

Clearly, apart from being variable in general relativity, an interpretation that "is perfectly valid and makes good physical sense", the speed of light is also constant in general relativity, and this interpretation "is perfectly valid and makes good physical sense" as well. The only problem comes from the formula

frequency = (speed of light)/(wavelength)

which is officially accepted in Einstein criminal cult. The frequency does vary with position in a gravitational field (gravitational redshift) and this is confirmed experimentally. If the formula is correct, and if the speed of light is constant (does not vary with position), then the wavelength must vary with position:

http://www.astronomynotes.com/relativity/s4.htm
"Prediction: light escaping from a large mass should lose energy---the wavelength must increase since the speed of light is constant. Stronger surface gravity produces a greater increase in the wavelength. This is a consequence of time dilation. Suppose person A on the massive object decides to send light of a specific frequency f to person B all of the time. So every second, f wave crests leave person A. The same wave crests are received by person B in an interval of time interval of (1+z) seconds. He receives the waves at a frequency of f/(1+z). Remember that the speed of light c = (the frequency f) (the wavelength L). If the frequency is reduced by (1+z) times, the wavelength must INcrease by (1+z) times: L_atB = (1+z) L_atA. In the doppler effect, this lengthening of the wavelength is called a redshift. For gravity, the effect is called a GRAVITATIONAL REDSHIFT."

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

http://space.newscientist.com/article/dn12...-star-size.html
"But light from the disc also loses energy – and is shifted to longer, redder wavelengths – because it has to work hard to escape the gravitational pull of the dense neutron star. This effect, called gravitational redshift, is predicted by Einstein's theory of general relativity, which posits that gravity bends the fabric of space-time."

So Einsteinians have one last step to make: the interpretation according to which, in a gravitational field, the wavelength "varies with position", an interpretation that "is perfectly valid and makes good physical sense", should be placed next to Einstein's original interpretation according to which, in a gravitational field, the speed of light "varies with position", an interpretation that "is perfectly valid and makes good physical sense" as well. I suggest textbooks should first give Einstein's original interpretation and then the alternative one, e.g. in the following way:

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.

In the 1920 book "Relativity: the special and general theory" he could have written: ". . . 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 [. . .] can claim an unlimited validity. A curvature of rays of light can only take place when the wavelength varies with position." This interpretation is also perfectly valid and makes good physical sense.

Pentcho Valev
pvalev@yahoo.com
Zephir
QUOTE (Pentcho Valev+Sep 7 2007, 11:15 AM)
Speed Or Wavelength Varies With Position?

It depends on the position of observer, i.e. the fact, whether (s)he is influenced by the same gravitational field, which is considered in change of light wave speed or frequency.

Not very bright person is required for understanding of such simple perspective, huh?
Ron
Pentcho,
Please study more GR before stating these absurdities. Space is not constant. If wavelength varies with position in a gravitational field that is distorted, you have to modify your simplistic Frequency = C / wavelength. Try looking it up. (http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html is a good reference).
Peace,
Ron
freethis
No it depends on position.

The origin of the wave is not referred too.

x = frequency times (Length)=(wavelength)
freethis
QUOTE (Zephir+Sep 7 2007, 02:43 PM)
It depends on the position of observer, i.e. the fact, whether (s)he is influenced by the same gravitational field, which is considered in change of light wave speed or frequency.

Not very bright person is required for understanding of such simple perspective, huh?

zeph I like this model a lot, can you make the 2 sets of red dots start in the middle, but go out in both directions? left and right, representing a standing wave?
rpenner
1) Pentcho Valev can quote whatever he wants, but he doesn't have one shred of evidence that the velocity of light or the wavelength of light is a function of position. Experiments in Sophia, Paris, Tokyo and New York all measure the same. In life and in GR, we say that the laws of physics are positionally invariant.

There is just one universe we have access to, so there can be but one physics.

2) But due to the Earth's rotation, Paris and New York are in relative motion. Observing each others clocks and wavelengths they observe a symmetrical time dilation and length contraction. What actually matters is the relative motion of the subject and observer, and this can be demonstrated in the laboratory. In life and in GR, we say that the laws of physics obey local Lorentz invariance.

I like experiments with muons because they show Lorentz invariance has nothing specifically to do with electromagnetism.

3) But between floors of the same building, there is a non-symmetric effect. In life and in GR, we say that the clock at radius R from the center of the Earth obeys a time dilation of factor √( 1 - 2 GM/Rc² ) = √( 1 - R0/R ) relative to a "clock at infinity." We know this, not because we have "clocks at infinity" but for small change in height, h, we can measure √[ ( 1 - R0/R )/( 1 - R0/(R+h) ) ] which for R >> R0 and R >> h >> R0, we approximate as √[ ( 1 - R0/R ) ( 1 + R0/(R+h) ) ] = √[ ( R² + hR - hR0 - R0²) / (R²+hR) ] = √[ 1 - (R0 + h) R0 / (R² + hR) ] ≈ √[ 1 - h R0 / R² ] = √[ 1 - 2 GMh/R²c² ] = √(1 - 2gh/c²) ≈ 1 - gh/c²

Where R0 = 2 GM/Rc², which is the radius of a black hole of mass M (rotating or not) and g = GM/R² is the surface gravity.

This was measured by the Pound-Rebka experiment. It is not something changing with respect to position. It is something that changes as light moves between positions.

So the thesis implied by the title of this thread has no support in experiment or modern theory.
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