Paper: A causal mechanism for gravity

[Mordred]

Well that would certainly involve a lot of antisymmetry relations. Acceleration caused a rotation due to rapidity. Torsion would give antisymmetry to the metric tensor. Ie to describe torsion using the metric tensor you would have to specify a direction of rotation.

What you actually need is a covector vector and a vector. The covariant vector is the column vectors while the vector is the row vectors. 

Using the two vectors above will preserve invatiance under coordinate transformations.

Gravity itself is a form of flux of the energy momentum stress tensor. 

With the Minkowskii tensor you have already made a coordinate choice (cartesian) so you can use the inner product of two vectors. Which will return a scalar value

[math]\mu\cdot\nu=s[/math] the Minkowskii tensor is orthogonal all orthogonal groups are symmetric and commute.

[math]\mu\cdot\nu=\nu\cdot\mu[/math]

However this would not be invariant under coordinate transformation so the column vector would use a covector.

Edited May 18, 2020 by Mordred

[SergUpstart]

17 minutes ago, Mordred said:

Well that would certainly involve a lot of antisymmetry relations. Acceleration caused a rotation due to rapidity. Torsion would give antisymmetry to the metric tensor. Ie to describe torsion using the metric tensor you would have to specify a direction of rotation.

What you actually need is a covector vector and a vector. The covariant vector is the column vectors while the vector is the row vectors. 

Using the two vectors above will preserve invatiance under coordinate transformations.

Gravity itself is a form of flux of the energy momentum stress tensor. 

This means that the description of gravity by using LITG will be more complicated than GR ??

[Strange]

!

Moderator Note

Can we stick to the topic of the thread please: which is rjbeery's "causal mechanism for gravity"

 

[Mordred]

35 minutes ago, SergUpstart said:

This means that the description of gravity by using LITG will be more complicated than GR ??

No I am describing a rank two tensor under GR ( though just the starting steps to understand a rank two tensor). I hadn't gotten into components of a vector. (A special rank two tensor would be the Dyad..

The reason you need a rank two tensor describe gravity is that you a gradient to describe gravity.

Edited May 18, 2020 by Mordred

[rjbeery]

  

4 hours ago, Markus Hanke said:

Time dilation is a relationship between clocks, it’s not a covariant quantity, and it isn’t local either. So, such a thing as a “time dilation field” does not make much physical or mathematical sense.

Couldn't we start with a mapping of gamma relative to some arbitrary observer (i.e. infinitely distant and inertial)?

 

1 hour ago, Strange said:

You still have not shown how this can produce the effects of gravity. Not even the simple Newtonian model. Are you going to do that? Or is this all just guesswork?

I wrote this paper as a Gravity Research Foundation essay which was limited to 1500 words. The references mentioned are highly relevant. For recent work you can Google "F=ma optics". Here's an example: https://aapt.scitation.org/doi/10.1119/1.14861

Before finding work that had already been done on this subject, I had numerically calculated light bending around the sun if we treat its gravity field as a graded refractive index. This was not easy using a spreadsheet because of precision limitations, but it produced the Newtonian prediction of .87 arcseconds. I also tried to visualize how a photon moving in a circuit could "gravitate" toward a higher refractive index. You can see below that I treat the circuit as an octogon whose face is parallel to the "gravity gradient", and that we get a prediction which is in 96% agreement. Note that when an entry shows "0.000" below it isn't actually zero - that's just a function of formatting of extremely small numbers. To be honest, this work is old and it would take me a bit to remember what I was doing here, but I've seen enough to continue working under the assumption that the analogy holds.

 

 

What I would really like is an analytic solution but that math is incredibly hard (for me). I've talked Physics and Math professors at UNL, and I've even met with two graduate math tutors, but no one is sure of the best way to tackle it. Studiot mentioned that Eddington did a derivation of sorts in another publication, and I'm going to look at that.

[swansont]

22 minutes ago, rjbeery said:

  I wrote this paper as a Gravity Research Foundation essay which was limited to 1500 words.

 

What paper? Is there a link?

[rjbeery]

10 minutes ago, swansont said:

What paper? Is there a link?

No, submissions aren't published but the essay is literally what I posted in the OP.

[Strange]

42 minutes ago, rjbeery said:

Before finding work that had already been done on this subject, I had numerically calculated light bending around the sun if we treat its gravity field as a graded refractive index. This was not easy using a spreadsheet because of precision limitations, but it produced the Newtonian prediction of .87 arcseconds.

Which is, therefore, wrong. Consider your hypothesis falsified. Time to move on.

And you still haven't shown that this can act as a theory of gravity.

 

[Mordred]

The statement of the photon gravitating to a higher refractive index in the above will not work for gravitational lensing.

Different frequencies of light respond differently in a medium.

(Prism being one example)

A Gravitational lens doesn't have the same effect. Ie a spectrograph looking at a gravitational lens will not see the same prismatic effect. Spacetime curvature doesn't depend on frequency.

(If you try to treat spacetime as a medium you will invariably get the wrong answers) I could easily falsify any medium association. 

Edited May 18, 2020 by Mordred

[rjbeery]

2 minutes ago, Mordred said:

The statement of the photon gravitating to a higher refractive index in the above will not work for gravitational lensing.

Different frequencies of light respond differently in a medium.

(Prism being one example)

A Gravitational lens doesn't have the same effect. Ie a spectrograph looking at a gravitational lens will not see the same prismatic effect.

This is addressed in the fact that the wavelength of the photon in the EM mass is what determines the mass of the particle.

13 minutes ago, Strange said:

Which is, therefore, wrong. Consider your hypothesis falsified. Time to move on.

And you still haven't shown that this can act as a theory of gravity.

 

I'm not sure what more you're asking for. If light moving in a circuit accelerates in the direction of higher refraction in a graded refractive index, and if GR time dilation is a graded refractive index, and if massive particles are nothing but photons moving in "circuits", then we have completed the analogy. I even postulated the difference between Newtonian gravitational effects (with small relative velocities) and Relativistic gravitational effects, which are twice as much, due to a greater percentage of a massive particle's photon path being perpendicular to the gravitational source.

[Strange]

12 minutes ago, rjbeery said:

I'm not sure what more you're asking for.

I would like to see some concrete evidence that your idea can model gravity. For example, deriving [math] F = G\frac{m_1 m_2}{r^2} [/math] or [math] r_s = \frac{2 G M}{c^2} [/math] using your model.

The only result you have come up with so  far is wrong.

12 minutes ago, rjbeery said:

I even postulated the difference between Newtonian gravitational effects (with small relative velocities) and Relativistic gravitational effects, which are twice as much, due to a greater percentage of a massive particle's photon path being perpendicular to the gravitational source.

This is just bizarre. You start from the fact that GR predicts gravitational time dilation to develop a theory that replaces GR (which would therefore invalidate your initial assumption). Then, when your model gives the wrong result, you use the correct result from GR to try and work out how to use other effects from GR to fudge your result so it looks correct.

As GR is so useful as the starting point of your model, for checking the result of your model and then coming up with a way of fixing the results of your model ... why not just use GR?

[Mordred]

Spacetime curvature does not involve any refractive index. The mass term cannot be described under refractive index. Or radiation pressure (pressure has directional components).

[Strange]

13 minutes ago, rjbeery said:

This is addressed in the fact that the wavelength of the photon in the EM mass is what determines the mass of the particle.

But you haven't calculated anything for massive particles. All you have calculated is the wrong value for lensing.

[Mordred]

11 minutes ago, Strange said:

Bt you haven't calculated anything for massive particles. All you have calculated is the wrong value for lensing.

Correct and never examined the effect of frequency in accordance to Snell's law.

Let alone the one way two effects of a medium on light as per the M and M experiments. 

(Lol a little side note I had the opportunity to prove a peer reviewed article wrong on applying Snell's law to describe gravitational lensing to a PH.D in astrophysics. He pulled his article off Arxiv)

Edited May 18, 2020 by Mordred

[rjbeery]

17 minutes ago, Strange said:

This is just bizarre. You start from the fact that GR predicts gravitational time dilation to develop a theory that replaces GR (which would therefore invalidate your initial assumption). Then, when your model gives the wrong result, you use the correct result from GR to try and work out how to use other effects from GR to fudge your result so it looks correct.

I'm not trying to invalidate GR in any way. I'm thinking that modeling GR in this way might give us new ways to analyze it. The .87 arcseconds is what you would get using the equivalence principle alone; it's also the Newtonian deflection prediction; it's also Einstein's original prediction in 1911. He later doubled that estimate to 1.75 arcseconds, but that is only for light, not mass. There are many ways to explain why light would deflect twice as much as mass, and I gave a plausible, physical reason.

27 minutes ago, Strange said:

But you haven't calculated anything for massive particles. All you have calculated is the wrong value for lensing.

I posted how an EM mass particle ("made of light") would behave in graded refractive field, and got a 96% agreement on the apparent local acceleration. That was the spreadsheet calculations above.

36 minutes ago, Mordred said:

Correct and never examined the effect of frequency in accordance to Snell's law.

I've never considered this, thank-you. The connection between wavelength and mass is based on the Compton wavelength for this electron. You can read about it here: http://home.claranet.nl/users/benschop/homepg2/electron.pdf

My immediate response would be that the medium of "spacetime" has no dispersion. Another possibility is that massive EM particles are made of the same frequency of light with varying numbers of photons in various topologies. The concept of EM mass is relatively new and I don't believe has gone beyond a modeling of the electron.

[Strange]

Just now, rjbeery said:

I'm thinking that modeling GR in this way might give us new ways to analyze it.

So you are taking some bits of GR and getting the wrong results. Then guessing that you might be able to patch this up somehow, possibly using other bits of GR. I can't see any insights here.

2 minutes ago, rjbeery said:

I posted how an EM mass particle ("made of light") would behave in graded refractive field, and got a 96% agreement on the apparent local acceleration. That was the spreadsheet calculations above.

I have no idea what that image shows nor what calculations you have done. But you are getting wildly inaccurate results.

And you still haven't demonstrated that you can derive [math] F = G\frac{m_1 m_2}{r^2} [/math] (or anything else) from your idea.

Quote

My immediate response would be that the medium of "spacetime" has no dispersion. Another possibility is that massive EM particles are made of the same frequency of light with varying numbers of photons in various topologies. The concept of EM mass is relatively new and I don't believe has gone beyond a modeling of the electron.

So you are just making up ad hoc excuses to try and fudge your results.

6 minutes ago, rjbeery said:

I'm not trying to invalidate GR in any way.

Then I suggest we just stick with GR. You are not contributing anything useful.

[Mordred]

23 minutes ago, rjbeery said:

 

I've never considered this, thank-you. The connection between wavelength and mass is based on the Compton wavelength for this electron. 

My immediate response would be that the medium of "spacetime" 

Spacetime isn't a medium. Any treatment of spacetime as a medium will be easily proven inaccurate to observational evidence.

 As to the first part. The geodesic equations do not involve electrons.

A good example is light curves in the FLRW metric. (Universe geometry) however after the CMB there are no free electrons and this no Compton scatterring.

 How one describes mass must also work in cosmology applications as well as near massive bodies.

GR and the FLRW are fully compatible theories that do not depend on any medium or specific particle composition.

[rjbeery]

22 minutes ago, Mordred said:

Spacetime isn't a medium. Any treatment of spacetime as a medium will be easily proven inaccurate to observational evidence.

Depends on the definition of medium, I suppose. If light travels through it, then it's a medium, is it not?

 

51 minutes ago, Strange said:

I have no idea what that image shows nor what calculations you have done. But you are getting wildly inaccurate results.

But you didn't ask any questions about the image, at all. And most people wouldn't consider 96% "wildly inaccurate". There are no fudge factors in this spreadsheet to get that result -- I described what I was going to analyze, and then I did so. Does it contain errors? Perhaps, and you're welcome to study it and give feedback. But I find it unfair to list what I haven't provided, and then, after I provide it, claim ignorance as to its significance while making no effort to understand it.

https://docs.google.com/spreadsheets/d/1S3htgtleWvubFKUSFw2I9qKjjIBo4tallq9NP6-XEeQ/

If I did this right, you can view and copy the spreadsheet above, after which you're free to adjust it all you want.

[Mordred]

17 minutes ago, rjbeery said:

Depends on the definition of medium, I suppose. If light travels through it, then it's a medium, is it not?

No light doesn't require a medium to travel. This is where it differs from sound waves. It was this very thought that led to Eather theories. The Michelson and Morley experiment is one of the numerous tests that proved the medium view incorrect.

 

Edited May 18, 2020 by Mordred

[rjbeery]

1 minute ago, Mordred said:

No light doesn't require a medium to travel. This is where it differs from sound waves.

Understood, but "something" curves in GR. The "medium" of spacetime does not behave like a physical aether but that doesn't prevent whatever spacetime is from having the equivalent of a refractive index. To claim otherwise is literally to deny that GR contains time dilation at all.

[Mordred]

What curves is the principle of least action which relates the potential of the field to the kinetic energy of the particle.

If you really want to understand curvature then you need to study the  Principle of least action with the geodesic equations.

(Do not mistake a field as a medium) a field is an abstract descriptive of values or mathematical objects under a geometry descriptive.)

9 minutes ago, rjbeery said:

Understood, but "something" curves in GR. The "medium" of spacetime does not behave like a physical aether but that doesn't prevent whatever spacetime is from having the equivalent of a refractive index. To claim otherwise is literally to deny that GR contains time dilation at all.

Of course it does. Spacetime has no refractive index...

Particles behave in accordance to how they couple with a field or other fields. The couplings is what lead to the mass terms.

Mass is resistance to inertia change.

Edited May 18, 2020 by Mordred

[rjbeery]

5 minutes ago, Mordred said:

Of course it does. Spacetime has no refractive index...

Particles behave in accordance to how they couple with a field or other fields. The couplings is what lead to the mass terms.

OK, then we can assign the refractive index to the global set of fields. Remember, we are calling this an analogy, but how does it change things if we declare that the varying index belongs to spacetime as opposed to the field(s) in spacetime? The math would be the same because the math (of time dilation) is ultimately determined by GR.

[Mordred]

No forget refractive index.

The correct application is Principle of least action via the Langrangian.

Which is completely different from refractive index.

How can you have a refractive index when the mean average number density of particles amounts to 5 protons per cubic metre in interstellar space ?

Edited May 18, 2020 by Mordred

[rjbeery]

4 minutes ago, Mordred said:

No forget refractive index.

The correct application is Principle of least action via the Langrangian.

Which is completely different from refractive index.

How can you have a refractive index when the mean average number density of particles amounts to 5 protons per cubic metre in interstellar space ?

This strikes me as an aesthetic objection, and you're entitled to that, but I think you'd agree that the mathematics of GR is pretty complex, difficult, and restrictive. If we produced a new way to attack problems it could be valuable.

[Mordred]

No I am a Professional Cosmologist with degrees in particle physics. I can prove any refractive index treatment of spacetime wrong.

I can do the same with any treatment of spacetime as a medium wrong. Lol all I have to do is point out previous research papers.

I have even been hired to research refractive indexes by a survey camera manufacturer. That grant paid my income for a year.

I have also done spectronomy research on a couple of gravity wells.

Edited May 18, 2020 by Mordred