[puppypower]

Consider, as an analogy for a photon, a boat traveling on the water. The boat is analogous to the particle, while the wake created by the boat is analogous to the wave aspect of the photon. If we had two tunnels under the bridge, the boat; particle, can only go through one tunnel at a time, while the wake, if spread out, can go through both tunnels.

The boat needs a constant supply of energy to keep moving at velocity V. This energy is needed to overcome friction between the boat and water. If the boat cuts the engines, the particle will slow, coast and then stop, while the wake will decay and finally stop. The speed of light is needed to maintain the wake/wave of the photon particles.

The question becomes how does a photon move through the medium of space-time and not slow down or speed up? What is the source of the propulsion energy?

If we assume the speed of light is the ground state of the universe, this implies all inertial references will be at higher potential. In this case, the constant speed of light would be connected to photons being constantly induced into the ground state ay C. The photons are constantly induced to higher potential; less than C by inertial. They cyclically drop back to the ground state; speed of light, while the energy differential is given off; motor that generates the wake/wave. 

One analogous way to look at this is connected to a house with a variety of electrical circuits, all using the same ground; earth. The ground is common to all the circuits and is at lower potential than any voltage/current configuration we may use. The potential difference between the inertial states, and the ground, is the energy potential used to drive the particle, which creates an analogous wake in space-time. This wake can become modified with the medium of space-time; red and blue shift, but the ground never changes, so the particles are always moving at C.

[marzosia2]

MOD EDIT: please keep your replies clear ,concise and relevant. Large, multiple posts of diagrams and no explanation will be treated as spam and removed.

[timey]

Consider, as an analogy for a photon, a boat traveling on the water. The boat is analogous to the particle, while the wake created by the boat is analogous to the wave aspect of the photon. If we had two tunnels under the bridge, the boat; particle, can only go through one tunnel at a time, while the wake, if spread out, can go through both tunnels.

The boat needs a constant supply of energy to keep moving at velocity V. This energy is needed to overcome friction between the boat and water. If the boat cuts the engines, the particle will slow, coast and then stop, while the wake will decay and finally stop. The speed of light is needed to maintain the wake/wave of the photon particles.

The question becomes how does a photon move through the medium of space-time and not slow down or speed up? What is the source of the propulsion energy?

If we assume the speed of light is the ground state of the universe, this implies all inertial references will be at higher potential. In this case, the constant speed of light would be connected to photons being constantly induced into the ground state ay C. The photons are constantly induced to higher potential; less than C by inertial. They cyclically drop back to the ground state; speed of light, while the energy differential is given off; motor that generates the wake/wave. 

One analogous way to look at this is connected to a house with a variety of electrical circuits, all using the same ground; earth. The ground is common to all the circuits and is at lower potential than any voltage/current configuration we may use. The potential difference between the inertial states, and the ground, is the energy potential used to drive the particle, which creates an analogous wake in space-time. This wake can become modified with the medium of space-time; red and blue shift, but the ground never changes, so the particles are always moving at C.

Fair enough PuppyPower... BUT... in Pound Rebka """Where"" in space time does this wave LENGTH exist if the distance between light source and receiver is held 'static', with respect to each other, on the basis that the oscillations of the speaker are creating a Doppler shift that cancels out the gravitational shift of the light?

[jeffreyH]

Maybe a little mathematics would clear things up... or maybe not.

[timey]

https://en.m.wikipedia.org/wiki/Doppler_effect

Quoted from link above:
"For waves that propagate in a medium, such as sound waves, the velocity of the observer and of the source are relative to the medium in which the waves are transmitted. The total Doppler effect may therefore result from motion of the source, motion of the observer, or motion of the medium. Each of these effects is analyzed separately. For waves which do not require a medium, such as light or gravity in general relativity, only the relative difference in velocity between the observer and the source needs to be considered."

[PmbNEP]

I learned that light travels at the same given speed no matter if a light source is static in a fixed place or the source is moving towards you in that same space.

What is it that decelarates a photon that is emitted from an object moving toward you with say half the speed of light to come back to exactly the fixed speed of light.

That's called the invariance of the speed of light. It's the second postulate of special relativity. It's referred to as a postulate because nobody knows why the speed of light is independent of the speed of source.

However you can think of the reason as due to the properties of spacetime. When you change from one frame of reference, e.g. the frame in which the source is at rest, to one in which the source is moving then you're changing to a frame where, as determined from the rest frame, distances parallel to the motion of the source are shorter and where time intervals are shorter, both in exact proportions so that the speed of light has the same speed in all inertial frames.

[timey]

That's called the invariance of the speed of light. It's the second postulate of special relativity. It's referred to as a postulate because nobody knows why the speed of light is independent of the speed of source.

However you can think of the reason as due to the properties of spacetime. When you change from one frame of reference, e.g. the frame in which the source is at rest, to one in which the source is moving then you're changing to a frame where, as determined from the rest frame, distances parallel to the motion of the source are shorter and where time intervals are shorter, both in exact proportions so that the speed of light has the same speed in all inertial frames.

Very good Pmb!!!

Now could you please tell me how, within the Pound Rebka experiment, a Doppler shift can be identified within the gravitational shift of light when there is no relative motion between the light source and the receiver other than the oscillations of the speaker cone... these oscillations of the speaker cone being the method of measuring the fact of the Doppler shift within the gravitational shift of light via cancellation of redshift blueshift frequencies...

[JoeBrown]

Now could you please tell me how, within the Pound Rebka experiment, a Doppler shift can be identified within the gravitational shift of light when there is no relative motion between the light source and the receiver other than the oscillations of the speaker cone... these oscillations of the speaker cone being the method of measuring the fact of the Doppler shift within the gravitational shift of light via cancellation of redshift blueshift frequencies...

The Pound Rebka experiment used MOTION produced by a speaker cone.  The gamma ray light source was mounted on a MOVING speaker cone, which induced doppler shift.

The argument that doppler shift occurred without motion is flawed.  There was movement.  It didn't require a lot of movement.  Since the distance was in nearly constant flux.  They recorded the phase of the speaker movement to account for doppler shift.

--

Now for my timely wizenhimer remark:  DOH

[NeT-HeaD (OP)]

Guy's
All your chatter about dopler dazzles me but . . .
it seems to me that only aplies to interaction between fotons emmited in a row one after another when emmited from moving source or observed by moving source. i wanted to keep the question simple by observing just the ONE photon and its behaviour when emmited form a source.

But hey. it's still very enlightning to follow your guys arguements
.

[timey]

The Pound Rebka experiment used MOTION produced by a speaker cone.  The gamma ray light source was mounted on a MOVING speaker cone, which induced doppler shift.

The argument that doppler shift occurred without motion is flawed.  There was movement.  It didn't require a lot of movement.  Since the distance was in nearly constant flux.  They recorded the phase of the speaker movement to account for doppler shift.

--

Now for my timely wizenhimer remark:  DOH

Joe - Again you entirely miss even the 'intended' purpose of the experiment itself.

For the last time -  A Doppler shift was created by mounting the light source in the centre of the speaker cone.  It is sooo obvious that the gamma ray source will move as per the vibration of the speaker that I thought it unnecessary of mention.  It's the entire premiss of the experiment!  They created the measuring Doppler effect using hertz and the subsequent vibration of the speaker in order to cancel out the blueshift redshift frequencies of the light undergoing gravitational shift.

Now then - listen very carefully...  For a Doppler shift in vibration to cancel out the frequencies of blueshift redshift, the frequencies of blueshift redshift must resemble exactly the vibration of the Doppler shift.  Therefore the 'motion' you insist is occurring for the light source, this motion 'actually being' the motion of the speaker, is resembled exactly 'in' the gravitational shift.  Note:  The gravitational shift distance in this experiment is 'static'.  There is no relative motion between the 'distance' of the gravitational shift and observation 'with respect' to the gravitational field, and therefore no """obvious"""" relative motion for a Doppler shift for light in this experiment in the gravitational field.

Redshift is synonymous with expanding distances, and blueshift with contracting distances, as per space time considerations!!!  Yet, as per Pound Rebka, we see a Doppler shift in the gravitational shift of light, measured by a vibration, caused by motion of a speaker receiving between 10 and 50 hertz, over a constant distance in the gravitational field between a light source and receiver that are experiencing no relative motion between themselves, other than the forward and 'backward' motion of a speakers vibration acting upon the light source.

How can there be a Doppler shift in the gravitational shift of light over a constant distance when the speed of light is constant?  What exactly is causing the 'motion' of this Doppler shift found within the gravitational shift of light in this instance?

P.S Net-Head, I'm sorry if we have digressed.  I'm not entirely sure what your interest is in one photon, but I'm pretty sure knowing about what happens to light in general can only help

[jeffreyH]

The Pound Rebka experiment used MOTION produced by a speaker cone.  The gamma ray light source was mounted on a MOVING speaker cone, which induced doppler shift.

The argument that doppler shift occurred without motion is flawed.  There was movement.  It didn't require a lot of movement.  Since the distance was in nearly constant flux.  They recorded the phase of the speaker movement to account for doppler shift.

--

Now for my timely wizenhimer remark:  DOH

Joe - Again you entirely miss even the 'intended' purpose of the experiment itself.

For the last time -  A Doppler shift was created by mounting the light source in the centre of the speaker cone.  It is sooo obvious that the gamma ray source will move as per the vibration of the speaker that I thought it unnecessary of mention.  It's the entire premiss of the experiment!  They created the measuring Doppler effect using hertz and the subsequent vibration of the speaker in order to cancel out the blueshift redshift frequencies of the light undergoing gravitational shift.

Now then - listen very carefully...  For a Doppler shift in vibration to cancel out the frequencies of blueshift redshift, the frequencies of blueshift redshift must resemble exactly the vibration of the Doppler shift.  Therefore the 'motion' you insist is occurring for the light source, this motion 'actually being' the motion of the speaker, is resembled exactly 'in' the gravitational shift.  Note:  The gravitational shift distance in this experiment is 'static'.  There is no relative motion between the 'distance' of the gravitational shift and observation 'with respect' to the gravitational field, and therefore no """obvious"""" relative motion for a Doppler shift for light in this experiment in the gravitational field.

Redshift is synonymous with expanding distances, and blueshift with contracting distances, as per space time considerations!!!  Yet, as per Pound Rebka, we see a Doppler shift in the gravitational shift of light, measured by a vibration, caused by motion of a speaker receiving between 10 and 50 hertz, over a constant distance in the gravitational field between a light source and receiver that are experiencing no relative motion between themselves, other than the forward and 'backward' motion of a speakers vibration acting upon the light source.

How can there be a Doppler shift in the gravitational shift of light over a constant distance when the speed of light is constant?  What exactly is causing the 'motion' of this Doppler shift found within the gravitational shift of light in this instance?

P.S Net-Head, I'm sorry if we have digressed.  I'm not entirely sure what your interest is in one photon, but I'm pretty sure knowing about what happens to light in general can only help

Now express that in terms even the most pompous can understand. At the moment it is simply unintelligible.

[timey]

Now express that in terms even the most pompous can understand. At the moment it is simply unintelligible.

Jeff - lol!

And for the pompous:

For a Doppler shift, caused by vibration, to cancel out the frequencies of gravitational blueshift redshift, the frequencies of blueshift redshift must resemble exactly the vibration of the measuring Doppler shift.

The measuring vibration of the speaker, ie: the phase, is 'just measuring' the same effect in the gravitational shift of light.  Except, and this is the important bit, oh pompous one , unlike the speaker cone, the gravitational field is NOT in motion.

Now try relating that back to Hubble's law!

[JoeBrown]

IMO, Hubble's law or constant or parameter is flawed because it simply does not account for gravitational shift.

[timey]

Joe - As far as I understand, and I am prepared to have my understanding called into question, redshift is thought to be indicative of an expansion between bodies of mass, ie: light source and receiver.  The Doppler shift of redshift is indeed an 'increase' in wave'length'.  Unfortunately GR refuses to provide an absolute reference frame for the universe, due to inconsistencies in measurement under the remit of the speed of light being constant.
IMO, the Pound Rebka proves an absolute reference frame within a gravitational field via redshift blueshift frequencies.  BUT... """Warning""" this requires a rethink on the nature of the phenomenon of time, and it's time dilation, contraction tendencies within the gravitational field.
IMO...the Pound Rebka proves inconsistencies in currently held physics theory.  A Doppler shift of light cannot occur in a gravitational field, unless there is relative motion of the observer, the source, or the field.
If you have got your head around the fact that the motion of the speaker creating a Doppler shift to counter and therefore measure a Doppler shift that is already and naturally occurring in the gravitational field, I'll feel like I've got somewhere in our discussion.

[JoeBrown]

Doppler and gravitational shift are two different phenomena we understand cause shift in frequency of light.

Doppler is pretty well understood because it's effects can be heard in sound waves, seen in light waves and works pretty good in radar.

Gravitational shift is a lot harder to detect, which was the purpose of the "Pound Rebka experiment."

They first measured the shift in light between statically separated source and receivers. Took measurements from top and bottom and noted that the shifts were equal and opposite, as predicted by Einstein / gravity shift.

They further metered the change in shift by comparing it to doppler shift produced by the motion of a speaker.  When they compared the phase (of the speaker motion) that canceled the opposing shifts as predicted, the experiment concluded gravity shift is in agreement with the prediction of GR.

GR purposefully does not provide an absolute reference because its premise is that everything is relative, tho the speed of light is about the closest it comes to an absolute frame of reference.

[timey]

Yawn...

Joe - I too can read the Wiki links and a lot more besides, and have been doing so consistently for over 7 years now.

Good luck in your understanding of physics...

Alan?
Pmb?
Jeff?

[alancalverd]

IMO...the Pound Rebka proves inconsistencies in currently held physics theory.

In everyone else's opinion, it shows that gravitational redshift can be measured and is exactly as predicted. But you are entitled to your opinion, which is much less boring.

[timey]

IMO...the Pound Rebka proves inconsistencies in currently held physics theory.

In everyone else's opinion, it shows that gravitational redshift can be measured and is exactly as predicted. But you are entitled to your opinion, which is much less boring.

Alan - you are sooo droll!

Fortunately, being as you are a physicist, and an intelligent one in my non-boring opinion , you will be of the irk to push the boundaries of knowledge in the way that people of true thinking capacity are wont.

https://en.m.wikipedia.org/wiki/Doppler_effect

Quoted from link above:
"For waves which do not require a medium, such as light or gravity in general relativity, only the relative difference in velocity between the observer and the source needs to be considered."

Could you please answer these following questions?

The Doppler shift link above indicates that a Doppler shift cannot be achieved without some relative velocity occurring between observer and source.
Is this true?

The Pound Rebka consists of a man made Doppler shift measuring a naturally occurring Doppler shift within the gravitational shift of light.
Is this true?

The Pound Rebka, apart from the speaker vibration used to create the man made Doppler shift, involves no relative difference in velocity between the observer and the source, and with regards to the phenomenon of natural Doppler shift being measured by the man made Doppler shift, the gravitational field causing the gravitational shift in the light is not experiencing any change in its distance or in its strength of gravitational force other than the changes contained within the remit of the distance of the experiment.
Is this true?

Because if these things are true, then it doesn't matter if the experiment showed that Einstien predicted the gravitational shift correctly, the point of interest is that if a natural Doppler shift of light can occur without any relative motion between observer and source in a gravitational field, then this calls into question the fact of redshift being indicative of an expanding, accelerating universe, because the Pound Rebka has indicated, viewed from this perspective, that there was no expansion or contraction of space time within gravitational shift in light.
If there was no expansion or contraction of the distance, then what has caused the relative motion of the naturally occurring Doppler shift in the gravitationally shifted light?  Both the distance within the gravitational field and the speed of light are constant!

[JoeBrown]

Okay, now I'm starting to understand your reasoning, tho I don't agree.

You've been terming all shift in frequency of light as doppler shift.  Even though doppler shift is only associated with differing in relative velocities.

It would have been clear if you stated that its "interesting that shift occurred in relatively static source/receiver".  But you did not, you called it doppler shift.

It is interesting that they found shift in light frequency to be equal and opposite in static relative motion in a vertical orientation, more so, because it is what evidence for gravitational shift they sought.

Would be less interesting if they also conducted the experiment in a horizontal orientation and produced the same results.  Then it wouldn't be thought to be the effect of gravitational shift or that it invalidates the principle and/or the experiment and wouldn't be considered evidence of gravitational shift.

[PmbNEP]

Very good Pmb!!!

Now could you please tell me how, within the Pound Rebka experiment, a Doppler shift can be identified within the gravitational shift of light when there is no relative motion between the light source and the receiver other than the oscillations of the speaker cone...

Doppler shift is function of the speed of the source and nothing else. The source of gamma rays is mounted in the center of the loudspeaker and is attached to the cone so that as a signal is sent to the speaker  the source moves back and fourth. Therefore there is a relative motion between source and receiver. There can only be a Doppler shift when the source is moving as is the case here.

Note: This has nothing to do with the original question so this is an off-topic discussion.