🚀 go-pugleaf

"Paul B. Andersen" <paul.b.andersen@guesswhatuia.no> wrote in message
news:47B9EB24.9070701@guesswhatuia.no...
> Max Keon wrote:
>> Paul B. Andersen wrote:
---

>>> Do you think the Pound & Rebka experiment would be
>>> considered to be a confirmation of GR if it had
>>> measured the opposite of what GR predicts? :-)
>>
>> GR predicts that clock oscillator frequencies are slower in a
>> gravity well, while the frequency of an inward traveling photon
>> increases.
>>
>> This was the purpose of the Pound and Rebka experiment
>> according to Brittanica;
>> -By Einstein's theory of general relativity a photon produced
>> -near the Earth's surface should be higher in frequency by 1.09
>> -parts in 1016 for each metre above sea level. In 1960 the U.S.
>> -physicists Robert V. Pound and Glen A. Rebka measured the
>> -difference between the frequencies of photons produced at
>> -different elevations and found that it agreed very closely
>> -with what was predicted.
>>
>> Pound and Rebka were not out to prove that an atomic clock runs
>> slower in a gravity well at all, they were out to prove that a
>> photon frequency decreases and wavelength increases as it travels
>> upward from a gravity well.

> What you don't seem to understand is that the (loosely expressed)
> statement "atomic clock runs slower in a gravity well" and the
> (loosely expressed) statement "a photon frequency decreases as
> it travels upward from a gravity well" express the same phenomenon.
> See below.
---

>>> That is, the frequency on the top is _higher_ than
>>> the frequency on the bottom.
>>
>> I know what the clock frequencies will be at the tower base and
>> tower top, but what will be the frequency of a photon that has
>> traveled from the tower base to the top? According to GR, it's
>> going to be _lower_ at the top than it was at the bottom.

> Please read the following carefully.
> We have a tower.
> If em-radiation is emitted from one end of the tower, and received at
> the other end, all frequencies must change by the exactly the same factor.
> That means that if the em-radiation is gamma, the frequency shift
> delta_f/f must be the same as when the em-radiation is RF.
> If the em-radiation is a series of pulses (or flashes),
> the repetition frequency of these flashes must also change by
> the same delta_f/f as above.
> Now, imagine that we have a clock at each end of the tower,
> emitting one flash per second (let the clocks be Cs clocks,
> emitting one flash per SI-second).
> If the em-radiation going up is shifted to lower frequencies,
> then the observer on the top will count fewer flashes from
> clock at the bottom, than from his own clock. While he
> is counting N pulses from his own clock, he will have counted
> only N-n pulses from the bottom clock. This process is cumulative,
> so he will see that the bottom clock is lagging more and more
> behind his own clock. The bottom clock is running slower than
> the top clock.
>
> The (loosely expressed)statement "clocks runs slower in a gravity well"
> and the (loosely expressed) statement "a photon frequency decreases as
> it travels upward from a gravity well" express the same phenomenon.
---

>> The Pound and Rebka experiment is very similar to the gravity
>> probe A experiment, in that a photon emitted from the radioactive
>> iron sample at the tower base is assumed to decrease in frequency
>> on the climb to the tower top. Confirmation of that being the
>> case appears to stem from the fact that resonant absorption of
>> the gamma ray emitted from what was initially the tower base
>> material does not occur until that material has been raised to
>> the same altitude as the receiver. That's the only time when the
>> emitted frequency matches the absorption frequency. So prior to
>> that event, the gamma ray frequency emerging from the tower base
>> material was either faster or slower. As with gravity probe A,
>> the assumption is that it was running faster. But atomic clocks
>> soundly reject that assumption.

> You seem to have grossly misunderstood how the P&R experiment
> was performed.
> Gamma rays were emitted from the bottom of the tower,
> and received at the top. The received frequency was measured,
> and found to be red shifted in accordance with the prediction
> of GR. As explained above, this also confirms the prediction
> of GR that (loosely) "clocks at a higher gravitational potential
> run faster when ."
> (The experiment was also run the other way, with the emitter
> at the top, and the receiver at the bottom.)
>
> What you are referring to above when saying "That's the only
> time when the emitted frequency matches the absorption frequency."
> is _how_ the frequency of the gamma rays was measured.
> The Mossbauer effect is basically the phenomenon that the spectral
> line of gamma from a crystal is very narrow because the whole
> crystal, and not only one atom, absorbs the recoil from the gamma.
> That means that the crystal can only absorb the gamma ray if
> the frequency is exactly the same as the one emitted. So if both
> the the emitting crystal at the bottom of the tower, and the receiving
> crystal at the top were stationary, nothing would be detected because
> the frequency wouldn't match.
> That's why the emitter crystal was mounted on a loudspeaker membrane
> which was driven at a low frequency.
> What was actually measured, was the speed of the crystal when
> the gamma-rays were absorbed at the top of the tower.
> The speed was then exactly right so that the Doppler shift
> cancelled the gravitational red shift. When the speed is known,
> the Doppler shift can be calculated.

That's the most comprehendable brief description I've ever come
across. I appreciate your attempt to enlighten me, but nothing
you have put forward so far has demonstrated how a photon
frequency can vary as a means of losing or gaining energy
depending on its travel direction relative to a gravity well.

Firstly, you state that the process is cumulative, which suggest
to me that the frequency transmitted from a low altitude clock
to a more elevated clock was actually higher than is observed
when it arrives there. Meaning that more ticks have been
transmitted than are actually received. It's not possible for
that to continue on indefinitely unless the space between the
two clocks is expanding. Even if the big bang theory allowed for
local expansion, it would be 1/44 of that required to store the
missing cycles.

The animation at
 http://members.optusnet.com.au/maxkeon/redshft2.html
demonstrates why that is impossible.

Then you infere that the photons have been redshifted according
to the time rate at the higher altitude detection point. That
there is no redshift at all. A picture is worth a thousand words,
so I've added a relevant image to the above web page.

That is the only possible redshift that can occur. It's an
illusionary redshift which only exists in time. There is no
physical redshift at all. According to the time rate at a
specific altitude the observed wavetrain carrying the clock
frequency, generated anywhere at all, is constant forevermore.
The frequency remains exactly as it was created regardless of
the environment through which it's traveling. In a big bang
universe, it will stretch along the expanding space, of course.

On that subject; If an atomic clock is placed centrally between
two i.e. Earth sized planets, it will be slowed according to
GM/r/c^2, by both planets. You know that this is so. Add any
number of similar planets at the same radius and each planet will
affect the clock individually. Then scatter a universe worth of
planets for as far as you like. Every one of those planets will
also affect the clock rate to some degree, but won't reduce or
alter in any way the effect from the local set of planets.

If there was no expansion, a wavetrain generated from the clock
frequency and transmiited into the universe will travel the
universe exactly as it was created. The frequency will be
perceived from anywhere according to the "anywhere" time rate.

Every electronic interaction in the early universe was therefore
extremely redshifted according to present day time. A 4000 K
blackbody spectrum wouldn't appear to us as anything like a
4000 K radiator. Expand what would already appear to us as a very
cold radiator and the big bang theory falls apart.

-----

Max Keon