[Physics] Gravitational Time Dilation and Gravitational Redshift - two separate things?

[Ilja Schmelzer]

Again, my point to replace the wave with hand-waving was to make clear
that the number of wave fronts received, if one looks at them in
absolute background time, does not change.  What changes is the
frequency, because it is measured with clocks, and clocks go slower,
so that the same number of wave fronts during the same absolute time
more means, in clock time, more wave fronts in one second, thus, a
blue shift.

And there is, nonetheless, also a relativistic mechanism for bending
light.  First, because there is also a length contraction, but the
main point is the change in the coordinate speed of light. That a
change in the speed of light causes a bending can be easily seen in a
prism.  And if one looks at GR through the Lorentz ether
interpretation, it is clear that it is the coordinate speed which
matters, and this coordinate speed changes.

In fact, it is a simple rule:  Whenever it seems that SR/GR have
something wrong, use the Lorentz ether interpretation to look at the
problem.  In the Lorentz ether, the problem usually disappears.

This is because the spacetime interpretation is in conflict with
common sense intuitions, the Lorentz ether not. The equations are the
same (see http://ilja-schmelzer.de/ether ) but all that is in conflict
with common sense disappears.

2018-12-05 22:30 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
> Hi Ilja,
>
>     Yes, I agree with you that " the only change in the frequency is
> because of the clocks (which have to be used to measure the frequency of
> the hand-waving", but the red-shift of the light can't be "the same thing"
> in my mind because, as you say, from the "point of view of the background
> time coordinate, there is no change in frequency".
> So if there is no change in frequency from the source to the receiver,
> there is no relativistic mechanism by which the EM wave is made to bend,
> since the bending is supposed to be caused by the progressive change in
> frequency through the gradient. Quite literally, for EM waves approaching
> the earth at an angle, the portion of the wavefront closer to the earth
> must contract compared to the portions further away, eliciting a
> progressive bend towards the surface, and Einstein attributes this to a
> change in frequency of the wave acted upon by the grav. gradient, which is
> something physical independent of the clocks. Einstein's idea also creates
> another paradox, that a receiver on the surface will receive more
> wave-fronts than are emitted by the transmitter at altitude - if this were
> true we would have a free-energy generating device!
>
> I think the only way out of this is to argue that it is the change in the
> speed of light with altitude and the associated change in wavelength that
> causes light to bend in the gradient, and frequency remains preserved.
> Einstein himself said in 1911 that this explanation was equivalent to his
> own (except for the energy change). Then there is only the one frequency
> effect due to the clocks and no problem with free energy. But then the
> black hole theory has to be a fiction.
>
> Doug
>
>
> On Wed, Dec 5, 2018 at 3:52 PM Ilja Schmelzer <ilja.schmelzer at gmail.com>
> wrote:
>
>> No, the signal will be blue-shifted only once.
>>
>> This can be best seen if one replaces the wave by a hand-waving person
>> and looks at the time when the light signal of "hand up" and "hand
>> down" arrive.
>>
>> If we look at this in coordinates which are natural for a stable
>> configuration, thus, a metric of the form g_mn (x^i) dx^m dx^n with
>> the metric coefficients depending only on the spatial coordinates, and
>> assume the handwaving guy as well as the observer at rest, the light
>> rays for "hands up" and for "hands down" are the same trajectories,
>> only with a shift in the time coordinate t.
>>
>> Thus, from point of view of the background time coordinate, there is
>> no change in the frequency.  Thus, the only change in the frequency is
>> because of the clocks (which have to be used to measure the frequency
>> of the hand-waving).   So, they are the same thing.
>>
>> 2018-12-04 22:12 GMT+01:00, Doug Marett <dm88dm at gmail.com>:
>> > Hi All,
>> >
>> >     This just came up in a question I had to my website - it has to do
>> with
>> > the Pound-Rebka experiment and whether gravitational time dilation of
>> > clocks and gravitational redshift of EM are two different things or the
>> > same thing. The problem is set out by L.B. Okun is plain language in an
>> > article here: https://arxiv.org/pdf/hep-ph/0010256.pdf
>> >    The essence of it is that if you take a clock and move it from the
>> > ground to the top of a tower, the clock should speed up in it's rate at
>> the
>> > higher altitude. If you then send an EM signal from this clock back to
>> the
>> > ground, Einstein says that the EM should be blue-shifted. However, this
>> > would mean that the signal sent to the ground has now been blue-shifted
>> > TWICE, once due to the clock speeding up,  and once due to the fall of
>> the
>> > EM through the gravitational gradient.
>> > However, the Pound-Rebka experiment finds that it is blue-shifted only
>> > once. So which effect is redundant, gravitational time dilation of
>> > clocks
>> > or gravitational red-shift of light? They can't be the same thing,
>> > since
>> > the latter is an operation performed on the EM during transit, and is
>> > supposed to make it bend. And the former is something which happens to
>> > clocks independent of EM signals sent between them.
>> > Interestingly, the experiment proposed by Okun to answer the question
>> > was
>> > performed in a slightly different form by Tom Van Baak as described
>> > here:
>> >
>> > http://leapsecond.com/great2005/
>> >
>> > Another link that is useful is the paper here which examines the math
>> used
>> > in the Pound-Rebka experiment and finds it is full of errors!
>> >
>> > http://milesmathis.com/pound.html
>> >
>> > Just wondering if anyone else is aware of this apparent contradiction
>> > in
>> > the relativistic thinking : )
>> >
>> > Doug
>> >
>>
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