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Old May 16th 15, 01:05 PM posted to sci.astro
Pentcho Valev
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Einsteiniana's hoax: Gravitational redshift = gravitational time dilation:

David Morin: "The equivalence principle has a striking consequence concerning the behavior of clocks in a gravitational field. It implies that higher clocks run faster than lower clocks. If you put a watch on top of a tower, and then stand on the ground, you will see the watch on the tower tick faster than an identical watch on your wrist. When you take the watch down and compare it to the one on your wrist, it will show more time elapsed. (...) This GR time-dilation effect was first measured at Harvard by Pound and Rebka in 1960. They sent gamma rays up a 20m tower and measured the redshift (that is, the decrease in frequency) at the top. This was a notable feat indeed, considering that they were able to measure a frequency shift of gh/c^2 (which is only a few parts in 10^15) to within 1% accuracy."

Question: "What is the greatest Physics experiment that has ever been done and why is it so good?" Jim Al-Khalili: "For me it was an experiment carried out by two Americans in the early 1950s and regarded as one of the classic tests of Einstein's General Theory of Relativity. Their names were Robert Pound and Glen Rebka and they proved that gravity really slows time down."

"A new paper co-authored by U.S. Energy Secretary Steven Chu measures the gravitational redshift, illustrated by the gravity-induced slowing of a clock and sometimes referred to as gravitational time dilation (though users of that term often conflate two separate phenomena), a measurement that jibes with Einstein and that is 10,000 times more precise than its predecessor."

"Einstein's relativity theory states a clock must tick faster at the top of a mountain than at its foot, due to the effects of gravity. "Our performance means that we can measure the gravitational shift when you raise the clock just two centimetres (0.78 inches) on the Earth's surface," said study co-author Jun Ye."

Yet clever Einsteinians know (and sometimes admit) that there is no gravitational time dilation, that is, gravitational redshift = variable speed of light:

Cristian Bahrim: "If we accept the principle of equivalence, we must also accept that light falls in a gravitational field with the same acceleration as material bodies."

Robert W. Brehme: "Light falls in a gravitational field just as do material objects."

Banesh Hoffmann: "In an accelerated sky laboratory, and therefore also in the corresponding earth laboratory, the frequence of arrival of light pulses is lower than the ticking rate of the upper clocks even though all the clocks go at the same rate. (...) As a result the experimenter at the ceiling of the sky laboratory will see with his own eyes that the floor clock is going at a slower rate than the ceiling clock - even though, as I have stressed, both are going at the same rate. (...) The gravitational red shift does not arise from changes in the intrinsic rates of clocks. It arises from what befalls light signals as they traverse space and time in the presence of gravitation."

Albert Einstein Institute: "One of the three classical tests for general relativity is the gravitational redshift of light or other forms of electromagnetic radiation. However, in contrast to the other two tests - the gravitational deflection of light and the relativistic perihelion shift -, you do not need general relativity to derive the correct prediction for the gravitational redshift. A combination of Newtonian gravity, a particle theory of light, and the weak equivalence principle (gravitating mass equals inertial mass) suffices. (...) The gravitational redshift was first measured on earth in 1960-65 by Pound, Rebka, and Snider at Harvard University..."

University of Illinois at Urbana-Champaign: "Consider a falling object. ITS SPEED INCREASES AS IT IS FALLING. Hence, if we were to associate a frequency with that object the frequency should increase accordingly as it falls to earth. Because of the equivalence between gravitational and inertial mass, WE SHOULD OBSERVE THE SAME EFFECT FOR LIGHT. So lets shine a light beam from the top of a very tall building. If we can measure the frequency shift as the light beam descends the building, we should be able to discern how gravity affects a falling light beam. This was done by Pound and Rebka in 1960. They shone a light from the top of the Jefferson tower at Harvard and measured the frequency shift. The frequency shift was tiny but in agreement with the theoretical prediction."

Pentcho Valev
Old May 17th 15, 08:10 AM posted to sci.astro
Pentcho Valev
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Posts: 8,078

"In 1960 Pound and Rebka and later, 1965, with an improved version Pound and Snider measured the gravitational redshift of light using the Harvard tower, h=22.6m. From the equivalence principle, at the instant the light is emitted from the transmitter, only a freely falling observer will measure the same value of f that was emitted by the transmitter. But the stationary receiver is not free falling. During the time it takes light to travel to the top of the tower, t=h/c, the receiver is traveling at a velocity, v=gt, away from a free falling receiver. Hence the measured frequency is: f'=f(1-v/c)=f(1-gh/c^2)."

The frequency measured at the bottom of the tower is f=c/λ, where λ is the wavelength. The frequency measured by the stationary receiver at the top of the tower is:

f' = f(1-gh/c^2) = (c/λ)(1-gh/c^2) = c'/λ

where c'=c(1-gh/c^2) is the speed of the light relative to the receiver. From the equivalence principle,

c' = c(1-gh/c^2) = c-v

is also the speed of light relative to an observer/receiver moving, in gravitation-free space, away from the light source with speed v:

"Doppler effect - when an observer moves away from a stationary source. ....the velocity of the wave relative to the observer is slower than that when it is still."

Clearly both general and special relativity are false - the speed of light varies as predicted by Newton's emission theory of light.

Pentcho Valev
Old May 18th 15, 11:58 AM posted to sci.astro
Pentcho Valev
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Posts: 8,078

A javelin graduated in centimeters is thrown downwards from the top of a tower of height h. Initially the centimeter marks pass an observer at the top of the tower with frequency f, speed c (not the speed of light of course) and "wavelength" λ (1cm):

f = c/λ

What are the frequency f', speed c' and "wavelength" λ' as measured by an observer on the ground? Newton's theory gives a straightforward answer (it is assumed that cc'-c):

f' = f(1+gh/c^2) = (c+v)/λ
c' = c(1+gh/c^2) = c+v
λ' = λ

where v=c'-c is the increase in speed.

Now let us answer David Morin's question:

David Morin: "A light source on top of a tower of height h emits flashes at time intervals Ts. A receiver on the ground receives the flashes at time intervals Tr. What is Tr in terms of Ts?"

If we compare the flashes to javelins thrown downwards at time intervals Ts (this comparison is allowed by Newton's emission theory of light), we see that each flash gets blue shifted because its speed at the receiver is c'=c(1+gh/c^2) (now c is the speed of light) and accordingly its frequency is f'=c'/λ=f(1+gh/c^2) - a result confirmed by the Pound-Rebka experiment.

On the other hand, the time intervals between the flashes remain unchanged: Tr=Ts. There is no gravitational time dilation.

Pentcho Valev

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