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  4. Is there a discrepancy with the equivalence principle?
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Is there a discrepancy with the equivalence principle?

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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1120 on: 22/05/2018 00:01:16 »
@Colin2B, I am just making use of this thread here to further discuss under the freedom of 'New Theories' a subject that I started on Physics board that @Janus was participating in here:

https://www.thenakedscientists.com/forum/index.php?topic=73266.msg541684#msg541684

Where I am trying to get to grips with the equatorial bulge. (Back to Shapiro Effect with you as and when you are up for it)

----------------------------
So repeating the consideration from that thread:

+relative speed, or centripetal speed = time going slower.

-minus relative speed, or centripetal speed = time going faster

+centrifugal force = time goes faster
-centrifugal force = time goes slower

higher GP = +centrifugal force + centripetal speed = time going faster

lower GP = -centrifugal force -centripetal speed = time going slower

+mass = time goes slower
-mass = time goes faster

Equatorial bulge sea level - Conventionally:

1: +mass = time goes slower
2: +height = +centrifugal force = time goes faster
3: + mass = -centrufugal force = time goes slower**
4: +centripetal speed = time goes slower
= same rate of time at sea level each longitude.

=slower, faster, slower, slower

= 3 slower + 1 faster


without bulge

+height = +centrifugal force = time goes faster
+ centripetal speed = time goes slower
= time goes faster

So +mass of equatorial bulge = time goes slower cancelling time going faster = same rate of time at sea level each longitude

Here we are saying that +mass is the same as -centrifugal force.

------------------------


Now under my theory everything is the same except:

+mass = time goes faster
-mass = time goes slower

Equatorial bulge sea level:

1: +mass = time goes faster
2: +height = +centrifugal force = time goes faster
3: + mass = -centrifugal force = time goes slower**
4: +centripetal speed = time goes slower
= same rate of time at sea level each longitude.

= faster, faster, slower, slower

= 2 faster, 2 slower.

without bulge

+height = +centrifugal force = time goes faster + centripetal speed = time goes slower
= 'time goes faster'

So +mass = time goes faster and +mass = -centrifugal force = time goes slower
= 'time goes slower'.

Add the above two together and 'time goes faster' and 'time goes slower' cancel
= same rate of time at sea level each longitude.

Here I am saying that + mass and -centrifugal force are NOT the same thing!

Now because where there is more mass/gravity, 'time goes faster', this gives a physical cause and effect description of why GRACE moves faster over the mountain than over the valley.
(This theory can be tested by placing a precision clock at LIGO to see how the clock ticks when a gravity wave hits.)
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1121 on: 23/05/2018 19:09:19 »
So going up a mountain:

1: +height = +centrifugal force = time goes faster
2: +mass = - centrifugal force = time goes slower
3: + mass = time goes faster
4: + centripetal speed = time goes slower

= 2 faster, 2 slower

Time running faster up a mountain (compared to sea level) being (as per my theory) due to:
less additional mass per extra height = less -centrifugal force
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Offline Janus

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1122 on: 26/05/2018 01:12:07 »
Quote from: timey on 22/05/2018 00:01:16
@Colin2B, I am just making use of this thread here to further discuss under the freedom of 'New Theories' a subject that I started on Physics board that @Janus was participating in here:

https://www.thenakedscientists.com/forum/index.php?topic=73266.msg541684#msg541684

Where I am trying to get to grips with the equatorial bulge. (Back to Shapiro Effect with you as and when you are up for it)

----------------------------
So repeating the consideration from that thread:

+relative speed, or centripetal speed = time going slower.

-minus relative speed, or centripetal speed = time going faster

+centrifugal force = time goes faster
-centrifugal force = time goes slower

higher GP = +centrifugal force + centripetal speed = time going faster

lower GP = -centrifugal force -centripetal speed = time going slower

+mass = time goes slower
-mass = time goes faster

Equatorial bulge sea level - Conventionally:

1: +mass = time goes slower
2: +height = +centrifugal force = time goes faster
3: + mass = -centrufugal force = time goes slower**
4: +centripetal speed = time goes slower
= same rate of time at sea level each longitude.

=slower, faster, slower, slower

= 3 slower + 1 faster


without bulge

+height = +centrifugal force = time goes faster
+ centripetal speed = time goes slower
= time goes faster

So +mass of equatorial bulge = time goes slower cancelling time going faster = same rate of time at sea level each longitude

Here we are saying that +mass is the same as -centrifugal force.

------------------------


Now under my theory everything is the same except:

+mass = time goes faster
-mass = time goes slower

Equatorial bulge sea level:

1: +mass = time goes faster
2: +height = +centrifugal force = time goes faster
3: + mass = -centrifugal force = time goes slower**
4: +centripetal speed = time goes slower
= same rate of time at sea level each longitude.

= faster, faster, slower, slower

= 2 faster, 2 slower.

without bulge

+height = +centrifugal force = time goes faster + centripetal speed = time goes slower
= 'time goes faster'

So +mass = time goes faster and +mass = -centrifugal force = time goes slower
= 'time goes slower'.

Add the above two together and 'time goes faster' and 'time goes slower' cancel
= same rate of time at sea level each longitude.

Here I am saying that + mass and -centrifugal force are NOT the same thing!

Now because where there is more mass/gravity, 'time goes faster', this gives a physical cause and effect description of why GRACE moves faster over the mountain than over the valley.
(This theory can be tested by placing a precision clock at LIGO to see how the clock ticks when a gravity wave hits.)
Sorry for taking so long to reply to this but I've been away on vacation. 
You cannot have +/- Relative speed If a clock is moving relative to you, you measure it as running slow. 
As far as tangential speed and "centrifugal force" go you can calculate time dilation using either one, but not both.  If you are calculating it from an inertial frame, then you use tangential speed, If you are calculating it from the non-inertial rotating frame, then you can use the potential due to the apparent centrifugal force.  What you cannot do is combine their effects, because they are just two ways of looking at the same thing.

If you want to work out the time dilation for a clock traveling in a circle all you need to know is its tangential speed.  (If you put two clocks in circular paths with different radii but traveling at the same tangential speed, they will run at the same rate even though one of them is undergoing a larger centripetal acceleration.

If you want to work gravitational time dilation in, you can do use the following for the total time dilation as measured from the inertial frame. 
T = t/sqrt(1-2GM/rc^2- w^2r^2/c^2)  where w is the angular velocity of the rotation.  If you want to do in the rotational frame you have to use the integral of the centrifugal force, and you end up with the same equation.

An oblate spheroid adds an additional complication.  First consider the scenario with no rotation.  This can be look at a like a spherical body with a world girdling "hill" around the equator.  In this situation, walking from either pole to the equator is walking "uphill" and you are moving to a higher gravitational potential, where clocks run faster than they do at the poles.  If the "hills" were mass-less then you could use the simply version of the gravitational time dilation equation to work out just how much faster. 
But since they aren't, it is a bit more complicated.  The way the mass is distributed will have an effect, and it would take a bit of additional calculation to work out just how much difference this will account for.

If the Body is rotating and had no gravity, then someone moving from pole to equator would be effectively moving "downhill" to a lower potential causing clocks to run slower at the equator than at the poles, since the tangential speed is greatest at the equator.

If, as we have with the Earth, both effects are in play and the degree oblateness is due to the combination of the Gravity of the body and its rotation due to the plasticity of the body, we get the case where these two time dilation effects combine in such a way that all clocks at mean surface "level" run at the same rate.  ( if the surface is bumpy), you'll get variations between depressions and rises.)
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Re: Is there a discrepancy with the equivalence principle?
« Reply #1123 on: 26/05/2018 19:32:10 »
Quote from: Janus on 26/05/2018 01:12:07
An oblate spheroid adds an additional complication.  First consider the scenario with no rotation.  This can be look at a like a spherical body with a world girdling "hill" around the equator.  In this situation, walking from either pole to the equator is walking "uphill" and you are moving to a higher gravitational potential, where clocks run faster than they do at the poles.  If the "hills" were mass-less then you could use the simply version of the gravitational time dilation equation to work out just how much faster. 
But since they aren't, it is a bit more complicated.  The way the mass is distributed will have an effect, and it would take a bit of additional calculation to work out just how much difference this will account for.

If the Body is rotating and had no gravity, then someone moving from pole to equator would be effectively moving "downhill" to a lower potential causing clocks to run slower at the equator than at the poles, since the tangential speed is greatest at the equator.

If, as we have with the Earth, both effects are in play and the degree oblateness is due to the combination of the Gravity of the body and its rotation due to the plasticity of the body, we get the case where these two time dilation effects combine in such a way that all clocks at mean surface "level" run at the same rate.  ( if the surface is bumpy), you'll get variations between depressions and rises.)

As you say, in adding the mass considerations of an oblate spheroid, that is also rotating (has in fact been caused by roatating), matters become more complicated than 2 time dilations cancelling each other out. And because our equitorial bulge consideration is oblate and rotating there would seem a little more finess to the reality that 'could' be examined.

My point here is that if one sets up a spinning wheel with 2 identical objects attached by string to the wheel - where 1 string is longer than the other - then the object on the longer string will travel at a greater speed, the outward force will be stronger, and the longer string will 'feel' a greater tension, than the shorter string.

GRACE is showing us that while our gravimeters 'on' the mountain register lower 'inward' gravitational pull, that gravity up a mountain is much stronger than in the valley.
Stronger gravity is supposed (not proven) to slow time down. Increased centripetal speed (relative motion) is proven to slow time down.
So at the top of a mountain there are 2 aspects (conventional physics) slowing time down.
It is proven that a clock ticks faster at the top of the mountain.
The 'conventional calculation' say that this is due to the weaker gravity that the clock feels at top of mountain (as per our gravimeters).

I am saying (as per GRACE) that the clock is not 'feeling' less gravity at the top of mountain. If it were feeling less gravity it would fly off the top of the mountain with the extra centrifugal force at that height.

So departing from 'how' conventional maths for time dilation are calculated...
What I see is the possibility that the clock/mass at top of mountain is 'feeling' a tension caused by two opposing forces. The inward pull of stronger gravity, and the outward push of stronger centrifugal force.

It would appear to me that with regards to our 'real life example' of time dilation on earth, which is  a non spherical/rotating example, that the 'conventional calculations' are considering that increased centrifugal force is the same thing as weaker gravity.
If the 'conventional calculations' factor in the total gravity at top of mountain, this slows time down, as well as the increase in centripetal speed slowing time down. It is then centrifugal force alone that speeds time up.

And, as I said in last post, adding gravity will decrease the outward centrifugal force, causing a 'minus centrifugal force' aspect to the calculation where added mass is causing height. (equatorial bulge)
This elicits 3 aspects that cause slower time versus 1 aspect that causes faster time, so 'conventional maths' cannot include the 'extra gravity' that the centrifugal force is opposing, because clocks will not run at same rate at sea level under a 3 aspects cause slower time and 1 aspect causes faster time remit.

That is why my theory suggests that adding gravity (adding mass) causes time to go faster, and minus centrifugal force causes time to go slower, where height is adding centrifugal force causing time to go faster, and increased centripetal speed at height causes time to go slower.
Now, with 2 aspects causing time to go faster, and 2 aspects causing time to go slower, these aspects 'can' cancel for same rate of time at sea level of every longitude of the equatorial bulge.

What I am suggesting @Janus is a different means of calculating the same observations.

My description (theory of +mass, or gravity = time goes faster) explores an alternative. An alternative that actually goes on to describe physical cause and effect mechanics (as an alternative to space geometry that is curved) for 'why' GRACE moves faster over the mountains...
...And provides a falsifiable prediction for a test of general relativity, where a precision clock can be placed at LIGO to undergo conditions (when a gravity wave hits) that do not incorporate a change in centrifugal force via hieght, and do not include a change in centripetal speed, but only include an addition of the gravity of the wave for the duration of the hit.

General Relativity predicts that clock will run slower.
My theory predicts that clock will run faster.

My theory is saying that the centrifugal force itself is having an effect on the clocks in addition to gravity having an effect on clocks.
Relativity considerations are saying that centrifugal force has an effect on gravity, and that gravity effects the clocks.
Relativity says that GRACE is travelling in slower time over the mountains in the stronger gravity, and that the acceleration is curvature related.
My theory is saying that GRACE is travelling in faster time over the mountains in the stronger gravity, and that the acceleration GRACE feels is due to the faster rate of time.

That is my theory.
(yes, this theory can describe grav.lens)
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Re: Is there a discrepancy with the equivalence principle?
« Reply #1124 on: 26/05/2018 19:42:30 »
In addition to post above:

So - in order for an attempt at examining/calculating under differing remit, it is important to recognise all the aspects at play here:

1/ The GRACE experiment itself, in determining the lead craft as accelerating in the stronger gravity, is bouncing electromagnetic radiation off the leading craft. That electromagnetic radiation 'should' (according to GR) be moving at a slower rate, in the slower time, in the stronger gravity.
This, of course, would account for the electromagnetic radiation taking longer to return when it is bounced off the lead craft over the mountains. But I hardly think for a minute that the GRACE experimenters will have neglected to account for this factor in stating the lead craft as 'moving faster' over the mountains...?

2/ Gravimeters display gals per cm per second squared.

A second squared up a mountain is different to a second squared in the valley. An up a mountain shorter second squared may affect magnitude of gals per cm measurement.
Where GRACE finds stronger gravity over a mountain, a gravimeter at top of mountain is 'potentially' measuring via a shorter second squared, as compared to a measurement in the valley and this will amount to less gals per cm per shorter second squared.

('If' the gravimeter interpretation of a second 'is' affected by it's position in the gravity potential, this aspect should account for a percentage of the gravimeters measurement of weaker acceleration, and interestingly (I think) in the negative 'could' be used to account for an internal tension (in atom) that 'causes' a downward attraction, (ie: gravity)
This being because if one views the opposing tensions of gravity versus 'centrifugal force and centripetal speed' as a tensor for electron frequency, and electron frequency as a tensor for the frequency with which a magnetic moment occurs, (where a more frequently occurring magnetic moment causes a greater downward attraction) then all this description is lacking is a tensor between electron frequency and the strong and weak forces, where this approach may (I think), describe the internal timing of time crystals as well as the internal timing (electron frequency) of any atomic structure, incuding the different atomic structures used as time keepers in different types of precision clocks, where any atomic structure will then increase it's internal timing in the higher GP)
« Last Edit: 26/05/2018 20:05:43 by timey »
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1125 on: 02/06/2018 20:26:59 »
So - given that GRACE shows that gravity is stronger at top of mountain than in valley, can we all agree that despite how time dilation is conventionally calculated via weaker gravity at the top of mountain, the clock is actually 'feeling' stronger gravity at the top of the mountain than in the valley?
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Offline Colin2B

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1126 on: 03/06/2018 21:14:16 »
Quote from: timey on 02/06/2018 20:26:59
So - given that GRACE shows that gravity is stronger at top of mountain than in valley,
GRACE doesn’t show this, it produces a Gravity anomaly map. Gravity anomaly maps show how much the Earth’s actual gravity field differs from the gravity field of a uniform, featureless earth surface with homogeneous density often called the ellipsoid. If you look at the theoretical calculation you will see that it assumes a homogeneous perfect sphere. If you are going to make comparisons with a real system you have to take into account uneven mass distribution, which is what GRACE does.
If we look at the Andes, on a uniform earth the value of g at sea level would be approx 9.8 and at a ht of 1km it would be 9.797, however if we take GRACE anomaly measurements into account the values would be less by 5x10-7 ie 9.7999995 and 9.7969995 respectively so the value of g at the top of the Andes is always less than that at the bottom so the tops are not feeling a stronger gravity than the valley.
However, it is still important to note what @Janus says, that the dilation does not depend on g but on the gravitational potential.

 
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Re: Is there a discrepancy with the equivalence principle?
« Reply #1127 on: 03/06/2018 22:26:33 »
So where the GRACE anomaly map shows red at top of mountains, and it states that anywhere red is showing a stronger gravitational acceleration, are you saying that that the red areas are not showing stronger gravitational acceleration?

I am aware that gravity potential is calculated as a 'theoretical calculation' assuming a homogeneous perfect sphere, and @Janus has shown how there are 2 methods of 'conventionally calculating' time dilation, but that they cannot be used together.
He said:
"As far as tangential speed and "centrifugal force" go you can calculate time dilation using either one, but not both.  If you are calculating it from an inertial frame, then you use tangential speed, If you are calculating it from the non-inertial rotating frame, then you can use the potential due to the apparent centrifugal force.  What you cannot do is combine their effects, because they are just two ways of looking at the same thing."

But our Earth is both rotating and has gravity anomalies that differ from the conventional 'gravity potential'...
...And what I want to do is to calculate the rotational aspects of relative motion time dilation, and the gravity potential anomalies aspects of time dilation together, because that is what we observe occurring on our planet.
...And I want to do this as a modification of general relativity where the factor of the gravity that clearly holds a clock to the top of a mountain 'is' included. This being because this extra gravity holding the clock to the mountain against the centrifugal force 'is' a factor that exists, isn't it?

Edit: I just looked at the GRACE gravity map again, and it clearly show red at the top of mountains, and it show a graph that suggests that red is equal to stronger gravity. I can't be reading that wrongly, can I?

https://en.wikipedia.org/wiki/Gravity_Recovery_and_Climate_Experiment#/media/File:Geoids_sm.jpg
« Last Edit: 03/06/2018 22:37:37 by timey »
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Re: Is there a discrepancy with the equivalence principle?
« Reply #1128 on: 04/06/2018 07:17:56 »
Quote from: timey on 03/06/2018 22:26:33
Edit: I just looked at the GRACE gravity map again, and it clearly show red at the top of mountains, and it show a graph that suggests that red is equal to stronger gravity. I can't be reading that wrongly, can I?
If you look at the scale you can see it describes the diagram as showing gravity field anomolies, and the units are in milligals so it is clearly not an absolute gravity measurement.
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Re: Is there a discrepancy with the equivalence principle?
« Reply #1129 on: 04/06/2018 07:38:14 »
Looking down from 200 km to the top of a mountain, there is obviously more mass immediately below the satellite than at the same altitude over the ocean, so there will be a positive gravitational anomaly compared with an idealised uniform sphere.

F = GMm/r^2, as always, but at only 200 km above a 6000 km knobbly geoid, M, r and the net direction of F on m (remember Maskeleyne at Schiehallion) do not approximate to the ideal isotropic and point values that apply in the laboratory or astronomy.
« Last Edit: 05/06/2018 08:15:30 by alancalverd »
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Offline Janus

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1130 on: 04/06/2018 16:52:27 »
Quote from: timey on 03/06/2018 22:26:33
So where the GRACE anomaly map shows red at top of mountains, and it states that anywhere red is showing a stronger gravitational acceleration, are you saying that that the red areas are not showing stronger gravitational acceleration?

Edit: I just looked at the GRACE gravity map again, and it clearly show red at the top of mountains, and it show a graph that suggests that red is equal to stronger gravity. I can't be reading that wrongly, can I?

Yes, you are reading the map wrong, In at least one way.   You keep wanting to interpret the GRACE readings as the strength of gravity at ground level, When they represent the fluctuations from the mean value of gravity measured at the altitude of the Satellites.  To get how gravity changes at ground level, you would have to combine this information with exactly how far ground level is from the center of the Earth at the point of interest.   The gravity map supplied by grace doesn't include this second bit of information.
Also, your insistent claim that red is at the top of mountains isn't always true.  In the GRACE map:

There are areas where higher gravity is associated with mountains, bit also areas where it is associated with low spots, such as out in the North Atlantic. You weren't under the impression that the "bumpiness" in the Gravity map represented elevation of the ground at that point were you? It is just a way of "doubling up" on how they represented the gravity measurements. They are shown in both color and and relief.
If you want to look for a correlation between the gravity map and geological features, this tectonic plate map is of interest.


Note that there is some correlation between where plates meet and high gravity areas( including that region in the North Atlantic.)  This is likely due to how local density of the crust is effected.    In certain places, this will also correlate with mountian ranges ( West coast of the Americas and the Himalayas, for example), but that is because these meeting points between plates are subduction  zones, where mountains tend to be built.


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Re: Is there a discrepancy with the equivalence principle?
« Reply #1131 on: 04/06/2018 17:33:01 »
Quote from: timey on 03/06/2018 22:26:33


But our Earth is both rotating and has gravity anomalies that differ from the conventional 'gravity potential'...
...And what I want to do is to calculate the rotational aspects of relative motion time dilation, and the gravity potential anomalies aspects of time dilation together, because that is what we observe occurring on our planet.
...And I want to do this as a modification of general relativity where the factor of the gravity that clearly holds a clock to the top of a mountain 'is' included. This being because this extra gravity holding the clock to the mountain against the centrifugal force 'is' a factor that exists, isn't it?


You don't need a "modification" of GR.   You just use the GR equation
Sqrt(1 + 2u/c^2- w^2r^2/c^2)

Here u is the gravitational potential at the point you are interested in.
w is the angular velocity of the rotation
r is the radial distance from the axis of rotation for you point of interest.

Working out the exact value of u when taking into account the various fluctuations in Earth's gravity field is the finicky part.  But to be honest, it isn't really going to amount to much.   

Gravitational potential is, in effect, a measure of energy per unit mass needed  to move from one point relative to the gravity source to a point an infinite distance from the gravity source. 
Now as you first start lifting an object from the surface of the Earth, variations in local gravity will have some effect on the energy needed to lift the object a given height when you are close to the surface, But as you get further from the Earth, this becomes less and less of a factor and it gets washed out by the overall effect of the total mass of the Earth. (the further you get from the Earth the more it gravitational behaves as a single point source).   This means that the small local variations in surface gravity have a minuscule effect on the gravitational potential at any point when compared to, say, the difference caused by being a few kilometers further from the center of the Earth by being on a mountain top vs being at sea level.
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1132 on: 05/06/2018 13:25:11 »
@Janus. I think you misunderstand my purpose.

I am quite simply interested in calculating time dilation using both the 'relative motion' and the 'gravity potential' equations in order to arrive at a 'contant rate of time' for sea level at each longitude of the equatorial bulge. (this being on basis that the equatorial bulge constitutes both changes in height and changes in speed occurring simaltaniously)

That is all I am interested in. You have said that 'adding in' the 'extra mass' of each increase in the equatorial bulge would require some additional calculation.

I am saying that 'if you add in' that extra mass that contitutes an increase in height of the bulge from poles to equator, where an aspect of +mass=time goes slower (conventional GR remit) must now be added to the calculation - this will NOT, under the conventional means of calculating, result in a constant rate of time at sea level of each longintude of the equatorial bulge.

You may tell me that my understanding is amiss somehow and 'show me how' adding in the extra mass under the remit of +mass=time goes slower WILL result in a constant rate of time at sea level of any longitude...

***In which case I will then AGREE with you that there isn't any necessity for a modification of GR.***
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Offline Janus

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1133 on: 05/06/2018 16:37:58 »
Quote from: timey on 05/06/2018 13:25:11
@Janus. I think you misunderstand my purpose.

I am quite simply interested in calculating time dilation using both the 'relative motion' and the 'gravity potential' equations in order to arrive at a 'contant rate of time' for sea level at each longitude of the equatorial bulge. (this being on basis that the equatorial bulge constitutes both changes in height and changes in speed occurring simaltaniously)

That is all I am interested in. You have said that 'adding in' the 'extra mass' of each increase in the equatorial bulge would require some additional calculation.

I am saying that 'if you add in' that extra mass that contitutes an increase in height of the bulge from poles to equator, where an aspect of +mass=time goes slower (conventional GR remit) must now be added to the calculation - this will NOT, under the conventional means of calculating, result in a constant rate of time at sea level of each longintude of the equatorial bulge.

You may tell me that my understanding is amiss somehow and 'show me how' adding in the extra mass under the remit of +mass=time goes slower WILL result in a constant rate of time at sea level of any longitude...

***In which case I will then AGREE with you that there isn't any necessity for a modification of GR.***
It has been already worked out.  There are two competing factors that determine the Earth's shape, its gravity and its spin.  If it weren't for gravity holding it together, its spin would tear it apart. As it is, a compromise is reached and we get an oblate spheroid.   The surface of this spheroid is a geoid, which means that local "vertical" is always perpendicular to the surface at any point of the surface. (which means that, unlike for the surface of a non-rotating spherical body, it doesn't always point towards the center of the body.).    This also means that the surface of this geoid is an equi-potential surface.  A good clue to this is that a fluid, such as water, will always settle to the lowest possible potential, and if the potential wasn't equal over the surface of the Earth, the oceans wouldn't follow its shape, but instead would pool up at either the poles or equator. 
The shift in mass towards the equatorial bulge in of itself factors in to the final shape. It is not an additional factor that has to be factored in later when doing calculations, it is already involved in causing the surface to be equi-potential.

Clocks at sea level tick at the same rate no matter how you try to calculate it.

Now if you wanted to, you could do all the math to determine the potential due to gravity alone at any point on the surface*, use that for u in the equation I gave in the my last post, along with angular velocity of the rotating Earth and the radial distance from the axis to get the time dilation that way, but you will get the same result.


* There is a formula for determining the gravitational potential over the surface of an oblate spheroid, but they assume a constant density throughout the body, and the Earth is not uniformly dense.
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1134 on: 05/06/2018 20:59:20 »
Ok - Yes I already know all of these aspects that you mention.

Quote from: Janus on 05/06/2018 16:37:58
Clocks at sea level tick at the same rate no matter how you try to calculate it.

The point is that I am interested in calculating time dilation in another way.

I am interested in calculating time dilation in another way because SR is compatible with Quantum, but GR isn't. (And GR has it's own limitations)

Anyway, I thank you for your input. It's kind of you to take the time, but I'm not sure you understand what it is I am trying to do here.

I am going to sign off now but will include, for the record, my falsifiable prediction for a doable experiment, including the remit of the experiment and why this experiment constitutes a test of GR that has not yet been conducted.

FALSIFIABLE PREDICTION FOR A DOABLE EXPERIMENT

A further test of General Relativity can be conducted by comparing clocks that are ONLY experiencing a change in gravity.

So far precision testing of GR with clocks has been conducted concerning change in height in the gravity potential, where the clock is, in addition to a change in gravity, also experiencing a change in centripetal speed and centrifugal force.
And precision testing of GR has also been conducted concerning a change in relative motion, where the clock is not experiencing a change in gravity.

https://www.sciencealert.com/portable-atomic-clock-measures-gravity-first-time-relativistic-geodesy

In Febuary this year portable precision clocks were tested for the first time.

It is my suggestion that these portable clocks should be placed in circumstance where ONLY a change of gravity is occurring, in order to confirm that General Relativity is indeed correct in assuming that an increase in gravity slows time down.

This could be conducted by placing a clock at 2 different locations at the same longitude, and at the same height above sea level, where there is a known density difference in the geology of the locations, and thus compare how they tick.
This will constitute only a difference in gravity.

Or - much more simply, just place a clock at one of the gravity wave experiments and record how the clock ticks differently when a gravity wave hits, as compared to how it ticks normally.
This will also constitute only a change in gravity.

General Relativity predicts that a clock that experiences only a change (increase) in gravity will tick slower.

My modification of General Relativity predicts that a clock that experiences only a change (increase) in gravity will tick faster.*

*The consequences of the remit of my modification are, of course, extremely far reaching.

However I just cannot do this trying to make people understand what it is that I am saying anymore.
Now that these precision clocks are portable, I daresay that they are going to be used to further test the tenets of General Relativity.

I have voiced my suggestion, and will now say no more.

Thank you.
« Last Edit: 06/06/2018 00:57:52 by timey »
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1135 on: 14/08/2018 17:46:52 »
Here is my first paper, now published at Journal of Space Exploration...

http://www.tsijournals.com/articles/TSSE-18-2146.pdf
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Offline timey (OP)

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1136 on: 25/08/2018 02:29:06 »
Quote from: timey on 14/08/2018 17:46:52
Here is my first paper, now published at Journal of Space Exploration...

http://www.tsijournals.com/articles/TSSE-18-2146.pdf

It's come to my attention that the link I provided is not working anymore, or maybe it never did and no-one told me (although it works ok for me, scratches head).

In anycase here is a link to the text version of my paper

http://www.tsijournals.com/articles/remixing-the-universe-by-vikki-ramsay-time-theory-13760.html


And here is the link where the PDF can be clicked on for the full version with diagrams:

http://www.tsijournals.com/journals/journal-of-space-exploration-current-issue.html
« Last Edit: 25/08/2018 02:59:59 by timey »
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Offline Colin2B

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Re: Is there a discrepancy with the equivalence principle?
« Reply #1137 on: 26/08/2018 07:06:50 »
Thanks, the link works.
I’ll have a read later.
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