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Author Topic: 4 a deeper discussion: Is distance an absolute invariant?  (Read 10296 times)

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #100 on: 18/02/2016 23:26:26 »
Removing light (massless) from the remit of gravitational potential. 

Incomplete sentence, but I think it is intended to contain something significant! Would you care to explain? We know that light is indeed affected by gravity.
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #101 on: 19/02/2016 00:08:43 »
This idea works on the basis that relativistic mass is redundant.  That light 'gets' it's energy from the gravitational field.

Yes of course we have observed that gravity affects light, but is it gravity affecting the light, or is there a possibility that it is gravity related time considerations, and changes in there-of, as massive bodies of mass come into alignment, that are causing these effects?  (As far as I can make out, there have been no laboratory tests that have bent light with gravity... Nearest I've found is this :
http://newscenter.lbl.gov/2009/07/20/testing-relativity-in-the-laboratory/
...and...I don't think gravity is involved)

Under the vastly wider scale of an inverted time dilation, observations of gravity lensing and star displacement would occur... just as we observe.
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #102 on: 19/02/2016 00:34:31 »
Point of fact, try this.

Draw a distance line on the horizontal, and graph slower, and faster rates of time (relative to earth) on a vertical, with slower rates (relative to earth) above the horizontal, and faster rates (relative to earth) below the horizontal.

Run your 'speed of light' vector along the horizontal into rates of time that are progressively slower until midpoint and then are progressively faster to end of distance.

This will create a parabola.

Now run a 'speed of light' vector along the horizontal, with time getting just a tinsy, tiny bit faster progressively, and then slower progressively, but just around the midpoint of the distance... and you will see a slightly inverted parabola.

This inverted parabola can be considered synonymous to gravitational lensing.
« Last Edit: 19/02/2016 01:04:47 by timey »
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #103 on: 19/02/2016 12:08:16 »
That light 'gets' it's energy from the gravitational field.
This sentence surely doesn't make sense? A photon is emitted from an electron transition which determines the photon energy. The  universal favorite isthe 21 cm hydrogen line which arises from a spin-spin interaction and is therefore gravity-invariant. We know that photons arising from sources with a strong gravitational field are red-shifted, i.e. appear to have less energy than expected from the quantum transition, so it ain't gaining energy from the gravitational field! 
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #104 on: 19/02/2016 13:15:27 »
Ok, I agree that my explanation is woolly and needs to be clarified, but first...

Can we agree that the Pound Rebka experiment can possibly be considered indicative that any redshift observations must be being observed at the point of weakest gravity between the light source and the receptor mass?

That if we observe a redshift of light from ground to bell tower on earth, that a hypothetical observer standing on a distant light source would also observe a redshift phenomenon as the light leaves the gravitational field of the light source?
 

Offline Colin2B

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #105 on: 19/02/2016 23:44:02 »
Can we agree that the Pound Rebka experiment can possibly be considered indicative that any redshift observations must be being observed at the point of weakest gravity between the light source and the receptor mass?
....point of weaker gravity??
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #106 on: 20/02/2016 00:14:38 »
Between the mass of another light source and the mass of our solar system... the gravitational field will reduce by the inverse square law until such point - this being dependent on the mass size of the other light source - that the gravitational field will start to increase by the squaring law (?), as the gravitational influence of our solar system takes effect.

The point of weakest gravitational field is at this point in the distance between the masses... the point just before the gravitational effects of our solar system start outweighing the reduction in gravitational force of the mass of the other light source.
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #107 on: 20/02/2016 01:41:39 »
Redshift is the difference between spectra generated at a distant body and the same spectrum generated locally. Conventional relativity says that every observer thinks is clock (or spectrum in this instance) is correct and the other one is wrong.
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #108 on: 20/02/2016 05:41:36 »
Yes... and this is a direct consequence of GR lacking an absolute reference frame in which to place these clocks, (or spectrum in this case).

The fact of GR lacking an absolute reference frame is a direct consequence of the notion that distance and length are variables.

Under the remit the 'top of the bell tower to ground' part of the Pound Rebka experiment, the light is shown to blueshift.  This indicates that it 'is' possible to chart time, or spectra, to a gravity field.  And of course, you don't have to remind me that this is exactly what they do do, and that this 'is' a working theory.

However... and just on the basis that sooo many theoretical physicists are moaning about the situation, (chuckle)... for reasons too numerous to list... it becomes interesting to consider another perspective.

The amount by which time gets faster in space, and the distance by which light travels a parallax distance at the speed of light do not match up.  It is the extra length in the wavelength that stretches this calculation of distance, in order to match a parallax distance. (I do believe?)

ITT simply states that it is the frequency of the light that is indicative of slower rates of time, in and across space, and that the extra length in a wavelength is time related.

Distances do not dilate.

And in reverse, an increase in gravity field, caused by a gravity wave, will blueshift the light that is measuring these 4km tubes.  And that contrary to accepted physics, this will cause a 'shorter' journey time, giving the impression, under current physics remit, and the 'calculation'... of time running slower for a blueshift, that the poles themselves have contracted...

My notion places 'Both Clocks' as being 'right'... and just uses Earth's frame of reference as the 'key'... as in a key to a chartable map.
« Last Edit: 20/02/2016 07:56:30 by timey »
 

Offline Ethos_

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #109 on: 20/02/2016 14:15:45 »


Distances do not dilate.

If there is one thing about physics I believe we can justifiably say, it is this: "When speaking about absolutes, I'm absolutely sure there are no absolutes." Reality is like Jello, No absolute solidity, no absolute time, no absolute length, no absolute position in space. The one possible exception being the speed of light in a vacuum. And even this standard might find argument amongst a few.

My two cents......................

« Last Edit: 20/02/2016 14:40:52 by Ethos_ »
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #110 on: 20/02/2016 17:46:34 »
Yes... and this is a direct consequence of GR lacking an absolute reference frame in which to place these clocks, (or spectrum in this case).
Not a question of GR "lacking" an aboslute reference frame, but recognising that there isn't one.

Worth checking your understanding of parallax distance, since you use the term quite a lot. It is just distance, inferred by parallax rather than direct measurement because we don't have a long enough tape measure to do it directly. So in principle you should be able to delete the word parallax without altering the underlying physics and overlying arithmetic of your argument. Unless you are claiming that your method reveals errors in the parallax method due to some other effect than the assumption of distance to the "fixed" star.
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #111 on: 20/02/2016 18:40:29 »
Ok - I did explain my understanding of a parallax distance earlier this thread, and will do so again to make the distinction between a distance, ie: 4km of tube, and a parallax distance.

A parallax distance is determined by method of angle.  By determining 'how' the star is progressing across our vision in respect to other light sources, both closer to us than the star in question, and further from us than the star in question, in distance.  This in conjunction with the luminosity of the star can determine the mass size of the star.

My distinction between a distance, and a parallax distance is born of the premiss of my diagram, which is recalculating the premiss of a parallax distance, determined by method of 'angle'.  My diagram will not work for a distance that is not determined by 'angle'.  It is the premiss of the parallax distance, the angles, the luminosity, and resulting mass size, that determines the parameters of measurement with which my diagram can then calculate.

My diagram is not stating that there is an error in the method of parallax, just an error of interpretation.

Again - can we agree that by means of the Pound Rebka experiment, that in viewing a redshifted light source, that we must indeed be viewing light at the point of weakest gravity field between the body of mass of the light source and the mass of our solar system...  The light will, by the remit of accepted physics, be blue shifted all the way back to the star, from our view of reference, from that point of weakest gravity field ... ?

It also occurs... that GR only explains the perihelion of mercury to a better degree of accuracy than Newtonian mechanics.  GR does not describe the scenario to an absolute exactness.

And... I am quite certain that it was not Einstein's intention that GR would be 'forced' to accept that it could not describe an absolute reference frame.  I personally believe it was the fact of this that gave him a headache over GR for the remainder of his life!
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #112 on: 21/02/2016 00:40:51 »
Again - can we agree that by means of the Pound Rebka experiment, that in viewing a redshifted light source, that we must indeed be viewing light at the point of weakest gravity field between the body of mass of the light source and the mass of our solar system... 
No. We have no idea where the minimum is and it certainly isn't on the surface of the earth.

GR can't describe an absolute reference frame because there isn't one, and its nonexistence is the basis of GR.
« Last Edit: 21/02/2016 01:16:27 by alancalverd »
 

Offline Ethos_

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #113 on: 21/02/2016 01:00:35 »
GR can't describe an absolute reference frame because there isn't one, and its nonexistence is the basis of GR.
Exactly Alan, and why people don't seem to grasp this is a mystery to me? It's precisely why it's called; "General Relativity" focusing attention upon the word: "Relativity". All measurements of; Space, time, mass, ect. are not absolutes, but are "relative" to each and every other factor within those calculations.
« Last Edit: 21/02/2016 01:27:11 by Ethos_ »
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #114 on: 21/02/2016 02:29:52 »
No. We have no idea where the minimum is and it certainly isn't on the surface of the earth.

GR can't describe an absolute reference frame because there isn't one, and its nonexistence is the basis of GR.

I did not suggest that the weakest gravity was on earth.  (You say there is no idea where the weakest point of gravity between 2 bodies of mass is?)

Now with regards to the Pound Rebka experiment, if you are going to be telling me that light is observed from the top of the tower to 'redshift' towards earth, from the perspective of the top of the tower, I will hang up my coat and retire.

Far as I am aware, the experiment showed that:  light moving from bottom to top of tower is redshifted from both perspectives, and light moving from top to bottom of tower is blue shifted from both perspectives.

Is this correct?

And... be that as it may, concerning GR, I can see the possibility of there actually being an absolute reference frame... and the benefits of having one.
Again - Inverted Time Theory is not synonymous to GR.  GR is only mentioned with regards to it being best current working theory, and because I was indeed invited to take someone's hand, earlier this thread, and guide them through GR, with respect to my ITT notion.

I am well aware GR has no absolute reference frame, and all the disadvantages there-of... and that it does not have an absolute reference frame because distance and length are variable.  (Let's not bring the fabric of space stretching faster than the speed of light into the matter.)

P.S.  Ethos, you are aware that GR has problems describing our universe?  That GR is a theory of gravity, and that gravity has yet to be linked to quantum, or the Maxwell equations?  Because if not, then please go read "The Trouble With Physics" Lee Smolin, before you make further comment here.
« Last Edit: 21/02/2016 03:39:42 by timey »
 

Offline Ethos_

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #115 on: 21/02/2016 03:02:07 »


P.S.  Ethos, you are aware that GR has problems describing our universe?  That GR is a theory of gravity, and that gravity has yet to be linked to quantum, or the Maxwell equations?  Because if not, then please go read "The Trouble With Physics" Lee Smolin, before you make further comment here.
With all due respect, I'll make comments here when I think there is good reason to.....................But appreciate the suggestion nevertheless.
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #116 on: 21/02/2016 10:03:44 »
Far as I am aware, the experiment showed that:  light moving from bottom to top of tower is redshifted from both perspectives, and light moving from top to bottom of tower is blue shifted from both perspectives.
No, it showed that the gravitational blueshift of a "falling" photon could be measured by matching it with the Doppler shift of a moving Mossbauer target.
 

Offline Thebox

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #117 on: 21/02/2016 10:22:29 »
Far as I am aware, the experiment showed that:  light moving from bottom to top of tower is redshifted from both perspectives, and light moving from top to bottom of tower is blue shifted from both perspectives.
No, it showed that the gravitational blueshift of a "falling" photon could be measured by matching it with the Doppler shift of a moving Mossbauer target.


I wasn't going to comment in this thread, but like Ethos stated I will post anywhere when I feel like it appropriate, I have the same forums rights as you all. I am sure this forum would not want to be discriminate which is a form of racism.

Alan I do not think you understood what Timey was saying, again maybe a syntactic ambiguity problem .

Imagine two stars  , A and B

Imagine A and B start of adjoined.   


AB

Imagine B sets out on a journey and relative to A and B neither knows who is moving.

A←→B

B travels way from A at the near speed of light  v=<c


relative to B , it is A that is travelling away at the near speed of light


A, observes B to redshift by the expansion of length  (doppler effect)


B, observes A to redshift by the expansion of the length. (doppler effect)


This is what timey was saying/asking.

You replied

''No, it showed that the gravitational blueshift of a "falling" photon could be measured by matching it with the Doppler shift of a moving Mossbauer target.''


This also applies, both affects are observed relative to perspective.   While A observes the light from A to B redshift , A also observes the light from B to A to blueshift. 


You have to imagine yourself in two different position perspectives simultaneously to understand both perspectives.











 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #118 on: 21/02/2016 12:06:09 »
Far as I am aware, the experiment showed that:  light moving from bottom to top of tower is redshifted from both perspectives, and light moving from top to bottom of tower is blue shifted from both perspectives.
No, it showed that the gravitational blueshift of a "falling" photon could be measured by matching it with the Doppler shift of a moving Mossbauer target.

My point being that there is nothing 'relative' going on between the 2 positions, top of tower, and bottom of tower, perspectives.  Blue shifted means approaching a gravity field, and redshifted means departing a gravity field...from both perspectives.

Ok, let's examine the idea of a photon 'falling' to earth.  A photon falling to earth is what we observe when we observe star light.  When this light comes within the gravitational field of Earth, that photon, having been redshifted away from the stars gravitational field, will blueshift as it 'falls' towards Earth.

Presumably it then is possible to subtract the blue shifted effect from the redshifted effect that we observe, to arrive at the correct redshift associated with that star. (?)

But 'where' are we observing this redshifted light?  Are we observing the redshifted light as a direct result of light being emitted from this star, from the position of the star?  Or are we observing the light as a direct result of the light having travelled to the point of distance whereas the light has become as redshifted as to the extent that the weakest point of gravity field has rendered it?
« Last Edit: 21/02/2016 12:08:21 by timey »
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #119 on: 21/02/2016 12:18:52 »
We are observing everything that happened to the photon from birth to absorption.

The business about the "weakest point of gravity" is irrelevant. We are seeing the integrated effect of all the gravitational fields and doppler shifts en route. Whilst we can compute the minimum gravitational potential and gradient between two fixed masses, there's all sorts of stuff moving about in the real universe. We know an apple is the result of 365 days of weather operating on one tree, but there's no way you can calculate the hottest or wettest day from the weight of the apple!     
 

Offline timey

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #120 on: 21/02/2016 12:56:16 »
Ok then - let's have a look at our closest light source, the sun, for simplicity.

The picture depicted in the link below states itself as vastly out of scale, but it does not state itself as geometrically incorrect.  Is it?

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

The light will redshift away from the sun, but when it comes under the influence of Earth's gravitational field,  it will start to blueshift...

And... as both bodies of mass are moving relative to each other, we know that the position in which we view the suns light, is not the position that the sun is in at the precise moment that we are viewing the light we view.  But if we were able to view the light of the sun instantaneously, would we observe a blue shifted streak from the position that we observe the light of the sun to be in, streaking across the sky to the position that the sun is now in?
(given that it all wasn't so damn blindingly bright that is...(chuckle) )
 

Offline puppypower

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #121 on: 21/02/2016 13:15:07 »
If you look at the sun, it has a spacetime well, with space-tim most contracted at the bottom of the well in the core of the sun. If you look in terms pressure, the material in the core of the sun is packed the most; lowest distances, consistent with contracted distance in the space-time well. However, time goes in the opposite direction, since the core has the fastest frequencies, while time in space-time runs slowest in the core. There are two layer of time.

The reason is gravity is an acceleration, which has the units of d/t/t (one part distance and two parts time) while space time is only d-t (one part distance and one part time). There is time missing from space-time, relative to acceleration.The extra time is connected to pressure and allows frequencies get faster instead of slower.

One needs to think in terms of gravity as two layers, with space-time only one of those two layers. The other layer is connected pressure. Distance in space-time is not invariant as everyone has pointed out. But distance in the extra layer of time, connected to pressure, is invariant and defines specific phases of matter. Specific phases of matter have specific distances, which are the same in all references. In SR, since this uses velocity; d/t, space-time is fully defined. The extra layer of time is not impacted so materials do not change. The younger twin in the paradox does not experience extreme pressure.

If we add the pressure variable, on top of space-time, we can see what appears to be variation in invariant distances, without any phase change.  We can see the hydrogen spectra, red shift, such that higher energy levels behave like lower energy levels, but in reality, the hydrogen atom is behaving in an invariant way, in the distant object. The standard hydrogen atom is how we infer motion, since we know this has to remain invariant and any chance is due to SR.

The answer is distance is variant with respect to space-time, but invariant with respect to the extra time (acceleration) connected to pressure. All the force of nature can exert pressure and be impacted by pressure. The extra time connected to pressure is how all the forces/accelerations are integrated, to define a unique summations of forces; characteristic phase.
« Last Edit: 21/02/2016 13:23:20 by puppypower »
 

Offline alancalverd

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #122 on: 21/02/2016 15:34:20 »
we know that the position in which we view the suns light, is not the position that the sun is in at the precise moment that we are viewing the light we view.  But if we were able to view the light of the sun instantaneously, would we observe a blue shifted streak from the position that we observe the light of the sun to be in, streaking across the sky to the position that the sun is now in?
(given that it all wasn't so damn blindingly bright that is...(chuckle) )

If you could observe the sun "instantaneously" c would be infinite by definition and no relativistic corrections would apply to anything.  And any photon leaving the sun will be red shifted from the point of view of an observer in a lower gravitational field, as shown experimentally by Pound & Rebka.

You don't need the sun or any other celestial body to play with red and blue shifts. As you have pointed out, the 57Fe mossbauer photon is entirely adequate for measurements in a terrestrial laboratory.   
 
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Offline Thebox

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #123 on: 21/02/2016 15:57:53 »
Ok then - let's have a look at our closest light source, the sun, for simplicity.

The picture depicted in the link below states itself as vastly out of scale, but it does not state itself as geometrically incorrect.  Is it?

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

The light will redshift away from the sun, but when it comes under the influence of Earth's gravitational field,  it will start to blueshift...

And... as both bodies of mass are moving relative to each other, we know that the position in which we view the suns light, is not the position that the sun is in at the precise moment that we are viewing the light we view.  But if we were able to view the light of the sun instantaneously, would we observe a blue shifted streak from the position that we observe the light of the sun to be in, streaking across the sky to the position that the sun is now in?
(given that it all wasn't so damn blindingly bright that is...(chuckle) )
OH ....how nasa observe the sun in different spectrum's changing the light when it hasn't changed
 

Offline jeffreyH

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #124 on: 21/02/2016 16:13:48 »
Take a mass m that is moving at 99.999...% the speed of light at constant velocity. Now from the perspective of the frame of reference of mass m,which can be considered inertial, we can launch a smaller mass so that from m's perspective it moves at 99.999...% the speed of light at a constant velocity. In theory we can repeat this procedure from each successive frame of reference. This is an infinite sequence. At some point we have to reach an absolute boundary past which it is now impossible to go. Like absolute zero, mass moving at c or being absolutely stationary.

This is the point at which relativity meets quantum mechanics.
 

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Re: 4 a deeper discussion: Is distance an absolute invariant?
« Reply #124 on: 21/02/2016 16:13:48 »

 

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