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  4. What is the difference between gravity potential, and gravity potential energy?
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What is the difference between gravity potential, and gravity potential energy?

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Offline GoC

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #140 on: 20/03/2017 11:00:06 »
Quote from: timey on 19/03/2017 19:49:18
Colin - In addition to my posts above:

First you say:

Quote from: Colin2B on 20/11/2016 11:54:14
Quote from: timey on 20/11/2016 11:23:56
But the clock IS blue shifted 'at' elevation... (this has been the whole point of the thread)
Not from our point of view. We were trying to convince you that it isn't blue shifted 'at elevation'.

And then you say:

Quote from: Colin2B on 19/03/2017 12:13:53
Quote from: timey on 18/03/2017 15:35:52
Because the equivalence principle states that the caesium atom ground state 'is' the same frequency in each and every gravity potential, and my model states that it's not.
I would say that 'the caesium atom ground state is measured to be the same frequency in each and every gravity potential when measured by an observer at the same location'.  Can't say if there is an absolute frequency for each GP because we can't measure it. I can't see how my view differs from what you are saying:

Quote from: timey on 18/03/2017 16:04:24
...and is it not true that if one observes a caesium atom placed at an elevated position from oneself that it is observed to be of a higher frequency?
Yes, when measured using the local time at the observer's location. But change the observer's location and the measured frequency changes.

As I say, I really don't see a real difference in what you are saying and certainly not one which would result in immense changes. However, you aren't going to change your view, and it isn't significant enough to me, so we will have to agree to differ and leave it at that.
Look forward to seeing the results/proof however.

If you were trying to convince me that the clock is not of higher frequency 'at elevation', then how can you say:
Quote
"I would say that 'the caesium atom ground state is measured to be the same frequency in each and every gravity potential when measured by an observer at the same location"
... ?

This implies that there 'are' frequency changes 'at' elevation, and that if one measures the frequency via the rate of time 'at' that elevation, one arrives at the frequency of ground state atom, therefore a clock 'does' have a higher frequency 'at elevation'!

I would have thought it significant to you that your understanding appears to be somewhat contradictory...and perhaps more significant that this contradictory understanding may not be yours alone.

Although both of you think your positions are contradictory they are not. Its all in the wording. Colin2B uses the word measured to be the same and that follows relativity and his model. You are using the Gods eye definition of frequency change with elevation following your model of relativity. You are both correct. Colin2B cannot say frequency change because that would be a claim of a matrix (Aether type) which main stream follows the MMX as proof there is no matrix in space. Something curves (dilates) so your position appears valid. The frequency seems to follow dilation rather than variable speed of light for GR. Atomic clocks can measure a change in tick rate as small as one foot. The wording is important when following main stream. All frames measure the same frequency but are not the same frequency. From main stream point of view they are correct as far as they are willing to go.
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #141 on: 20/03/2017 11:52:30 »
Quote from: Colin2B on 20/03/2017 08:16:10
Quote from: GoC on 19/03/2017 12:49:54
I do not think he meant that. Wording has to be accurate for the correct meaning. Can you find where that statement was made?
Yes GoC, wording has to be accurate as you say. Given the context of the link provided the wording requires (and deserves) a fuller answer than a simple misleading yes no. Don't have time at the moment, but if have in next couple of days I will write out so we can see where there is common ground and why we try to use very specific wording.

Colin - In the NIST thread of last year that I posted a link to in a post above and copied and pasted that comment from you saying that you and everyone else were trying to convince me that a clock does not have a higher frequency 'at elevation' - you and others posting on that thread ridiculed me for saying that a clock's frequency 'is' higher 'at' elevation.
You all told me that the observation was shifted 'from' that elevation and that when in that coordinate with that clock the clock would be ticking normally.

There is an immense difference in stating that an observation is shifted 'from' another coordinate, and stating that the observation is shifted when you go 'to' that coordinate and measure the observation with the local time of that coordinate.

The first states that the frequency change doesn't really occur it only looks like it's occurring when observed from another coordinate in the gravity potential.

The second states that the frequency change does really occur, and that when measuring that frequency with the local time 'at' that coordinate, that the frequency will be ground state.

Measuring an observed invariant frequency via variable timings will result in differing frequencies.
Measuring the changing frequency in differing gravity potentials via invariant time will result in differing frequencies.
Measuring the observed changed frequency via the observed changed tick rate will result in an invariant frequency, this being ground state for the caesium atom.

If we have cleared up this long standing misunderstanding of an observation of a clock being shifted 'from' another coordinate, then I'd like to talk about the fact that light in the gravity potential is shifting frequency in the opposing direction to a clock...

A clock shifts to a higher frequency in the weaker gravity field.
Light shifts to a higher frequency in the stronger gravity field.
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Offline GoC

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #142 on: 20/03/2017 14:31:16 »
Quote from: timey on 20/03/2017 11:52:30
Quote from: Colin2B on 20/03/2017 08:16:10
Quote from: GoC on 19/03/2017 12:49:54
I do not think he meant that. Wording has to be accurate for the correct meaning. Can you find where that statement was made?
Yes GoC, wording has to be accurate as you say. Given the context of the link provided the wording requires (and deserves) a fuller answer than a simple misleading yes no. Don't have time at the moment, but if have in next couple of days I will write out so we can see where there is common ground and why we try to use very specific wording.

Colin - In the NIST thread of last year that I posted a link to in a post above and copied and pasted that comment from you saying that you and everyone else were trying to convince me that a clock does not have a higher frequency 'at elevation' - you and others posting on that thread ridiculed me for saying that a clock's frequency 'is' higher 'at' elevation.
You all told me that the observation was shifted 'from' that elevation and that when in that coordinate with that clock the clock would be ticking normally.

There is an immense difference in stating that an observation is shifted 'from' another coordinate, and stating that the observation is shifted when you go 'to' that coordinate and measure the observation with the local time of that coordinate.

The first states that the frequency change doesn't really occur it only looks like it's occurring when observed from another coordinate in the gravity potential.

The second states that the frequency change does really occur, and that when measuring that frequency with the local time 'at' that coordinate, that the frequency will be ground state.

Measuring an observed invariant frequency via variable timings will result in differing frequencies.
Measuring the changing frequency in differing gravity potentials via invariant time will result in differing frequencies.
Measuring the observed changed frequency via the observed changed tick rate will result in an invariant frequency, this being ground state for the caesium atom.

If we have cleared up this long standing misunderstanding of an observation of a clock being shifted 'from' another coordinate, then I'd like to talk about the fact that light in the gravity potential is shifting frequency in the opposing direction to a clock...

A clock shifts to a higher frequency in the weaker gravity field.
Light shifts to a higher frequency in the stronger gravity field.

This is the part where main stream will not venture. To say light has momentum down a gravity well is wrong by Relativity. SOL being constant. Light created in a higher energy state remains the same wavelength as it travels down a gravity well and will appear blue shifted by the lower energy state's detector. The measurements change while the physics relationship of energy to timing remain the same in every frame. So when you move a wavelength detector from one position to another down a gravity well the detector changes calibration to the new energy state of measurement (more dilated energy state with a longer measuring stick).

This is why frequency is measured to be the same in every frame. Main stream will not allow any change to the accepted no matrix position. You are arguing for a matrix by your position.

Either you believe light has momentum to be blue shifted down a gravity well as main stream suggests (violating Relativity) or you believe something in space is being curved (dilated) as a physical existence for a photon.

Calling a photon virtual does not excuse it from being physical. If it is physically coming from the electron than it violates relativity. The only choice is energy and mass are two separate fractal masses of density. Energy is the matrix of space or relativity is incorrect. Main stream will not go that step. It would invalidate the BB.

Your position also suggests light changes wavelengths. When you discuss frequency of a clock you are comparing tick rates between frames in SR and dilation gradient in GR for equivalency. The dilation of space energy increases down a gravity well. This means PE decreases because energy is less dense per volume of space (expanded). This increases the electron travel distance in space reducing the tick frequency. The tick rate follows the dilation of energy reducing the PE to the center of mass.

timey you are correct it would have a major impact on physics with a paradigm shift in their model. Their math is correct for observations. It would just be their subjective interpretations that need tweaking. No expansion or contraction of the universe and no BB would be the two losers. GR red shift with SR Universe rotation from galaxies adding red shift.

Once a photon is created it does not change wavelength. The shift is due to the energy level of the position of the detector.
« Last Edit: 20/03/2017 14:35:46 by GoC »
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Offline Colin2B

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #143 on: 21/03/2017 00:03:36 »

Timey, it is entirely possible that there was a misunderstanding and we were all talking at cross purposes. As GOC says, wording is important, but also, context is important.  Before I spend time  describing where we agree and disagree let's look at context and wording to see if there really is an issue.

In the context of the NIST thread, it was our understanding that you thought there was an anomaly in the NIST results compared to the Pound Rebka results which you summed up as:

NIST = upper frame blue shifted
Pound Rebka = lower frame blue shifted.

Your 2 statements do not specify the locations from which the measurements were taken however, we were quite clear that there was no conflict between NIST and Pound Rebka and that both results were predicted by GR.

In terms of blue shift, it is expected in GR and Alan confirmed it e.g.:
Quote from: alancalverd on 20/11/2016 09:13:57
You are almost absolutely correct. To be pedantic, the photon is blue shifted "from", not "at" the top of the tower.
but note the pedantic importance of the relative position of the measurement.

It was also in this same context that my comments were made e.g.:

Quote from: Colin2B on 20/11/2016 11:54:14
Quote from: timey on 20/11/2016 11:23:56
(It may be that Relativity didn't predict that atoms are blue shifted in elevation, but it is most certainly not nonsense that they are because it is proven by the NIST experiment...  And if a cesium atom is blue shifted at elevation, a gamma ray source will be as well.)
NIST did not prove this. The Al ion was not blue shifted in its frame at elevation.
Note I specify frame at elevation, in other words when measured at its elevation.
Note for GoC- Al refers to the new (as of 2010) optical 'clocks' which were used in this experiment, smaller and much more accurate than the caesium std. They were not actual clocks/frequency counters but only frequency sources. Evan & I posted details in the thread if you are interested.

So let's have a look at the areas from your recent post where there could be misunderstanding,

Quote from: timey on 20/03/2017 11:52:30
You all told me that the observation was shifted 'from' that elevation and that when in that coordinate with that clock the clock would be ticking normally.
As explained in that thread the elevated clock frequency was measured as a difference relative to the fixed clock at the lower level. It was not measured in the local time frame at the elevation. This is all explained in the NIST article which was posted in the thread. I don't see any point in going over it again.

Quote from: timey on 20/03/2017 11:52:30
There is an immense difference in stating that an observation is shifted 'from' another coordinate, and stating that the observation is shifted when you go 'to' that coordinate and measure the observation with the local time of that coordinate.
That is true. If you do go to that coordinate and measure in local time you will not get a frequency shift - that's why NIST measured frequency at elevation relative to the time at the lower location.

Quote from: timey on 20/03/2017 11:52:30
The first states that the frequency change doesn't really occur it only looks like it's occurring when observed from another coordinate in the gravity potential.
Not sure I would agree. The frequency shift is real it's just that what value you measure varies according to where you measure from. If I am in a plane at 500mph and chasing another doing 600, I would say relative speed 100. But someone chasing at 400 would say relative 200. Both measurements are real.

Quote from: timey on 20/03/2017 11:52:30
The second states that the frequency change does really occur, and that when measuring that frequency with the local time 'at' that coordinate, that the frequency will be ground state.
i know what you mean, but that's why relativity refers to proper measurements and coordinate measurements - proper frequency is measured locally.
Just a point of clarity, ground state refers to the electron transitions in the atom, which determine the frequency it emits. This does not change when an atom is moved to a higher GP, or when observed from a different elevation, the electron transition do not move to higher energy levels causing higher frequency photons. This is why current physics views the frequency of the atom as constant at all elevations. If it did change you would see a different spectrum of lines at elevation.

Quote from: timey on 20/03/2017 11:52:30
If we have cleared up this long standing misunderstanding of an observation of a clock being shifted 'from' another coordinate,
If we truly have and you are ok that NIST and Pound Rebka are consistent with current physics.
If you disagree, then we have to agree to disagree because this has been done to death in the other thread.

Quote from: timey on 20/03/2017 11:52:30
then I'd like to talk about the fact that light in the gravity potential is shifting frequency in the opposing direction to a clock...

A clock shifts to a higher frequency in the weaker gravity field.
Light shifts to a higher frequency in the stronger gravity field.
Don't see any point in discussing the obvious. Clocks tick faster at elevation (time runs faster) compared to lower, as a consequence of this the measurements of light frequencies vary depending on where they originate from and are measured from.


All my comments are made re current physics and I appreciate that you might have a different view from current physics, and that's ok in this section.
« Last Edit: 21/03/2017 00:11:13 by Colin2B »
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Offline GoC

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #144 on: 21/03/2017 02:42:32 »
Quote from: Colin2B on 21/03/2017 00:03:36

Just a point of clarity, ground state refers to the electron transitions in the atom, which determine the frequency it emits. This does not change when an atom is moved to a higher GP, or when observed from a different elevation, the electron transition do not move to higher energy levels causing higher frequency photons. This is why current physics views the frequency of the atom as constant at all elevations. If it did change you would see a different spectrum of lines at elevation.

Colin2B

   This is a subjective opinion about seeing different spectrum of lines at elevation proving the electron transition do not move to higher energy levels causing higher frequencies. Timey is correct to follow frequency with tick rate. And the ground state transition could be different at different elevations. If they were the same transitions at different elevations that would destroy equivalence between GR and SR.

Follow my reasoning. Dilation is real and as real as tick rate change of clocks. It is the change in the ground state transition at different levels that change the clocks tick rate. Dilation (gamma term) expands the transition in space but the mass also expands when the electron transition increases lower in a gravity well. All detectors are equally expanded to automatically correct for the new dimensions in the gravity well. The detectors remain calibrated to each and every frame. If this were not true the speed of light would not be measured to be the same in every frame or elevation. The electron and the photon both travel through expanded space as confounded in every frame. Energy expands so the electron travels further and the photon travels further. Mechanical and light clocks tick at the same rate in every frame. Your measuring stick increases. Physics is the same in every frame.

How could that happen if the electron transition did not change from frame to frame. Relativity would not work.

You are confusing measured length with a fixed length. Nothing is fixed!!!! Not even the measuring devices.
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #145 on: 21/03/2017 03:09:28 »
Quote Colin:
Quote
All my comments are made re current physics and I appreciate that you might have a different view from current physics, and that's ok in this section.

In answer to your post above GoC's:

No - I do not have a different view from current physics, what I have done is form an alternative view, (lacking the actual maths), of time versus distance within current physics that gives a different and interesting picture that I am trying to describe here because I think it can be mathematically calculated to interesting results.

I do not disagree with the Pound Rebka results, but can see an alternative explanation within same results.

The reason for the discussion of the NIST thread in the first place was born in that I had been trying to discuss my observation that light is shifted to a higher frequency as it gets closer to M, and the atoms frequency is shifted to higher frequency when placed further away from M.

But the pertinent part here is that you say the atom is shifted in frequency, and that the nucleus isn't.
My model examines the possibility that the nucleus is also shifted, that the nucleus does have a higher energy, and that the emitted photon is of higher frequency than it would be if emitted at the lower potential.
The photon viewed 'from' the lower potential 'at' the lower potential, because light can only be viewed when it arrives, will be an observation that the photon has been shifted from the higher potential.
But by how much has it been shifted by the change in gravity potential, and how did it shift?
... Clearly the maths in service are describing the situation adequately, but on the basis that there are still unknowns, is there room for manoeuvre?

If whatever rate the nucleus is doing it's thing at is affected as are the transitions between the electron states at higher gravity potential, then all actions will be increased in rate.
So as an experimental train of thought one could examine the possibility that the rate that photons are emitted at affect the frequency and energy of the photon, but that the relationship is proportional. i.e. that the rate of time increases between the electron transitions are not linear to the energy and frequency increases of the emitted photon.... (not sure if I'm using the maths terms correctly here)
... and that the light is emitted at a higher frequency in the higher gravity potential relative to the frequency that it is emitted at in the lower potential, and is shifted to a higher frequency again by the change in gravity potential when it arrives at the observer in the lower gravity potential...
...And it makes both of these shifts because a) it was emitted by an emitter with higher energy (quicker time) at the higher gravity potential, and b) as a photon it was shifted by the higher energy (quicker time) g-field at lower gravity potential.
The quicker time closer to M being the 3rd time dilation of my model that gives cause to the acceleration of gravity.
It all gets pretty complex then when applying this remit to the Mossbauer receiver, where the temporal rendition of space dilation renders SR as part of the remix, and applied to the frequencies applied to the emitter, and so on.  But I'll stop there on that one.

So really Colin - my model is just a remix of current model maths and a change in interpretation of observation, where I am not disagreeing with current theory, but am instead saying that if you consider this, and look at that like so, that all the same maths will be valid, but for differing reasons that describe the same observations.

So on the basis of an explorative venture.
Question:
What do the electron transitions of an atom have to do with the emission of a photon?
Are electron transitions related to quantum energy levels?

https://brilliant.org/wiki/energy-level-and-transition-of-electrons/

...and if the frequency of the atom's electron transitions is greater at higher gravity potential, then the quantum energy level will be higher, so it would be impossible for it to emit anything other than a higher energy photon, perhaps?

This is the thought process that when applied as +energy = time contraction (shorter seconds) to the blackbody atom's light emissions can result in a continuum in quantum.
This giving Planck's h constant a whole new meaning and function within the maths.
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Offline Colin2B

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #146 on: 21/03/2017 14:49:42 »
Quote from: GoC on 21/09/1974 15:40:15
[/size]This is a subjective opinion about seeing different spectrum of lines at elevation proving the electron transition do not move to higher energy levels causing higher frequencies.
What I was specifically talking about was the ground state vs electrons moving to higher energy levels in the atom.
Quote from: timey on 21/03/2017 03:09:28
What do the electron transitions of an atom have to do with the emission of a photon?
They are the 'cause' of the emission
Quote from: timey on 21/03/2017 03:09:28
Are electron transitions related to quantum energy levels?
Yes. The transitions are the 'moves' between energy levels. The ground state is the lowest level and results in the lowest energy photons. If the electron transitions take place from higher energy levels the photons have higher energy. Note this is a quick and dirty explanation.If the transitions were being made from higher energy levels in an elevated atom that ought to be noticed by an observer at that elevation.However, one thing I didn't mention last night (long post,  very late) is that if you decide in your theory to assume that the energy levels of the ground state are 'lifted' then you could consider that the ground state is emitting higher energy photons.
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Offline jeffreyH

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #147 on: 21/03/2017 18:53:22 »
If the clock is held against gravity then does it radiate simply due to being in a non inertial frame? Not the same as energy transitions but can it be detected? Or is it in a frequency too low to be detected?

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Offline jeffreyH

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #148 on: 21/03/2017 18:55:46 »
Could one component of the CMBR be due to all the mass in the universe that is being held against gravity by electromagnetic and other forces?
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Offline alancalverd

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #149 on: 22/03/2017 17:18:03 »
Quote from: timey on 18/03/2017 16:04:24
...and is it not true that if one observes a caesium atom placed at an elevated position from oneself that it is observed to be of a higher frequency?

Yes, assuming you are talking about the master frequency of a cesium clock. Or indeed any clock that doesn't use a pendulum. The fact is well established.
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Offline alancalverd

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #150 on: 22/03/2017 17:24:42 »
Quote from: timey on 20/03/2017 11:52:30

A clock shifts to a higher frequency in the weaker gravity field.
when observed from a lower gravitational potential than the clock
Quote
Light shifts to a higher frequency in the stronger gravity field.
when observed from a lower gravitational potential than the source.

If you stick to the observed facts and standard terminology, you won't confuse yourself.
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #151 on: 22/03/2017 19:06:40 »
In answer to your post before last:

The reason I asked was because the clock when measured via the rate of time it is ticking at results in atoms ground state frequency, but this suggests that the ground state frequency of the atom is greater in the higher gravity potential.

In reply to post above:

...And when there is no observer to observe the light, does the light shift frequency in the changing gravity potential, or not?
Does light shift in the gravitational field?
Because if it does, then can we 'please' talk about how light is of a lower frequency in the weaker g-field?
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #152 on: 22/03/2017 21:09:30 »
Quote from: alancalverd on 22/03/2017 17:24:42
Quote from: timey on 20/03/2017 11:52:30

A clock shifts to a higher frequency in the weaker gravity field.
when observed from a lower gravitational potential than the clock
Quote
Light shifts to a higher frequency in the stronger gravity field.
when observed from a lower gravitational potential than the source.

If you stick to the observed facts and standard terminology, you won't confuse yourself.

You know - I am actually a little offended by your post Alan.
I am not confusing myself or anyone else.

It's high school physics that light on the outbound shifts frequency in the higher gravity potential.
It's high school physics that one can only view light when it reaches one's eye...
Therefore an observation of the red shifted light would occur only for an observer in the higher gravity potential.
So what?

Quite clearly the light on an outbound trajectory will still shift frequency in the higher gravity potential wether it is observed or not, therefore why are you stating me as confused please?

Light, on the inbound, or the outbound, is of a lower frequency in the higher gravity potential.
If you put an observer in the higher and the lower gravity potential, and ask them to take turns pointing a light source at each other, they will confirm this fact to be the case...

What's the problem?
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Offline alancalverd

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #153 on: 22/03/2017 23:09:24 »
The problem is that your two statements appeared to be mutually contradictory because they were imprecise.
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #154 on: 23/03/2017 00:36:32 »
Ok - so to be precise:

Light on the inbound and on the outbound will have a lower frequency in the weaker gravity field, or higher gravity potential, whichever you prefer.

The clock will have a higher frequency when observed in the weaker gravity field, or higher gravity potential, whichever you prefer, when observed 'from' the lower gravity potential.

When placing oneself in the higher gravity potential, one is measuring the frequency of the clock held relative to the tick rate of the clock at that gravity potential, and the frequency of the clock is ground state.  But if one observes the clock in the lower gravity potential, and in observing that the lower gravity potential clock is running slower than the clock one is with at elevation, one then uses the rate of time of the lower clock to measure the frequency of the elevated clock, the frequency of the elevated clock will again be higher than ground state, as observed when one was with the lower gravity potential clock.

Which means that a clock's frequency is always increased in the weaker gravity field, or the higher gravity potential...
And that lights frequency is always decreased in the weaker gravity field, or higher gravity potential.
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Offline alancalverd

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #155 on: 23/03/2017 08:24:29 »
Best advice, from Physics 101, is to stick to the observed facts and express them clearly, precisely and unambiguously, using a common vocabulary. (That's why I hate priests, politicians and philosophers, and don't have much time for economists either.)

"Inbound" and "outbound" are meaningless without reference points. To and from where? Where observed?

Don't confuse  field strength, which is the differential of potential, with potential.

Don't misappropriate "ground state".

Whatever the source, its frequency appears to be higher when observed from a lower gravity potential, as predicted and observed.  That's all there is.
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Offline timey (OP)

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #156 on: 23/03/2017 12:58:19 »
Inbound and outbound is clearly towards or away from M.
What else would it be?
How else could I say it?
...light>>M, light<<M?

If one knows the value of M there is no need for an observer.  The maths are there to understand what light and the clock are doing in the space surrounding M.

I haven't been directly discussing field strength in relation to gravity potential, yet, but if you look at the wiki link for gravity potential there is a diagram that shows quite clearly that the higher potential is in the weaker field.

Go to the moon where the value of M is lesser, the gravity potential at h from M(moon) will also be higher in the weaker gravity field of the moon.

Why am I misappropriating 'ground state'?
If one measures the frequency of the caesium atom at any gravity potential using the tick rate of a clock at that gravity potential, then the frequency of the atom is always 9,192,631,770Hz, and that 'is' ground state.

Observed and predicted - and yes, that is all there is - because no physical cause/s are given for the mechanics of the phenomenon...
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Offline GoC

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #157 on: 23/03/2017 14:22:48 »
Timey,

    You were not being precise in your wording leading to ambiguity. A trained physicist uses well defined wording in order to remove the ambiguity.

Quote from: timey on 23/03/2017 00:36:32
Ok - so to be precise:

Light on the inbound and on the outbound will have a lower frequency in the weaker gravity field, or higher gravity potential, whichever you prefer.


 Where was the light created? In a higher or lower PE? It will have the same frequency on the return destination.

Quote


The clock will have a higher frequency when observed in the weaker gravity field, or higher gravity potential, whichever you prefer, when observed 'from' the lower gravity potential.

You can only use measured to be.

Quote

When placing oneself in the higher gravity potential, one is measuring the frequency of the clock held relative to the tick rate of the clock at that gravity potential, and the frequency of the clock is ground state. 


In that position.

Quote

But if one observes the clock in the lower gravity potential, and in observing that the lower gravity potential clock is running slower than the clock one is with at elevation, one then uses the rate of time of the lower clock to measure the frequency of the elevated clock, the frequency of the elevated clock will again be higher than ground state, as observed when one was with the lower gravity potential clock.

There is no standard of time and there is no standard ground state to measure against. All observations are relative. Physics is the same in every frame because every measurement has the same ratio of relativity. There is no rest frame.

Quote

Which means that a clock's frequency is always increased in the weaker gravity field, or the higher gravity potential...
And that lights frequency is always decreased in the weaker gravity field, or higher gravity potential.


Frequency is decreased is ambiguous as to what decreased is being referred. Light is energy and speed. The photon is measured to be blue shifted down a gravity well.

The real question is whether the PE changes measurements or momentum of light causes the measurement. To strictly follow the relativity postulates it would be the PE as being dilated rather than light changing speed. There is observation for dilation in GR. The position of the sun is behind the horizon but we still observe the sun as not having set by observation. This proves the observed position is not the actual position in space. It is also accurate for SR observations where we never have a perpendicular view.
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Offline alancalverd

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #158 on: 23/03/2017 17:32:08 »
Quote from: timey on 23/03/2017 12:58:19
If one measures the frequency of the caesium atom at any gravity potential using the tick rate of a clock at that gravity potential, then the frequency of the atom is always 9,192,631,770Hz, and that 'is' ground state.
No. It isn't the "frequency of the atom". There are umpteen frequencies associated with an atom. It's the frequency of the photon that is associated with the  transition between the two hyperfine ground states of the electrons in the  cesium  atom.

Apropos fields, imagine a small source  subject to two gravitational field vectors at right angles, say  midway between Earth and Mars and offset from the line joining them. The  blue shift we observe depends only on which planet we are standing on, not the net field vector at the source. That is to say that it depends on gravitational potential difference, not field. 

This is the sort of pedantry that get Galileo into trouble, and without which we would still be stuck in the dark ages of superstition.

"The observer" is a convenient fiction who turns up all over physics, but without that irritating little man on Google Earth, we wouldn't know which way we are looking, and therefore would have no idea what we are looking at.
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Offline Ethos_

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Re: What is the difference between gravity potential, and gravity potential energy?
« Reply #159 on: 23/03/2017 18:44:45 »
Quote from: GoC on 23/03/2017 14:22:48

There is no standard of time and there is no standard ground state to measure against. All observations are relative. Physics is the same in every frame because every measurement has the same ratio of relativity. There is no rest frame.

I completely agree with you GoC, and the study of  Relativity concerns the measure of (t,l, and m) of one frame "Relative"to another frame and is not meant to be relative to any proposed "universal common now". No such "universal common now" or universal present can be used as a standard. The expression "universal common now" is IMHO, virtually meaningless to the Physicist.
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