Why intristic curvature is better than gravitomagnetism?

[Duda Jarek]

It's far from widely known fact that before Einstein's theory, there was Heaviside's simpler approach to make gravitation Lorentz invariant - by using a second set of Maxwell's equations - with e.g. density of mass instead of density of charge

http://en.wikipedia.org/wiki/Gravitomagnetism

 

This much less philosophically controversial theory (matter is not prisoned in infinitely thin submanfold of something with which it doesn't interact ... not allowing for wormhole-like solutions...) agrees well with most of observations (?), even with Gravity Probe B. Some papers says that even in better way:

http://www.mrelativity.net/Papers/14/tdm5.pdf

 

There can be also found strong arguments, that electromagnetic field also causes time dilation - for example while measuring muon lifetime in muonic atoms:

http://www.springerlink.com/content/wtr11w113r22g346/

 

My interest on this subject started while I was working on some model in which the main dynamics was local rotations in 4D and it occurred that it leads to natural unification of electromagnetism and gravitomagnetism - spatial rotations gives Maxwell's equations, while small rotations of time axis (kind of central axis of light cone), gives the second set of Maxwell's equation - for gravity (5th section of http://arxiv.org/abs/0910.2724 ).

 

What do you think about it?

Why 'the only proper approach': intristic curvature is better than gravitomagnetism?

[swansont]

 

There can be also found strong arguments, that electromagnetic field also causes time dilation - for example while measuring muon lifetime in muonic atoms:

http://www.springerlink.com/content/wtr11w113r22g346/

 

That's a paper from 1981. Anything more recent?

[Duda Jarek]

Yes - it's 30 years old paper from "General Relativity and Gravitation" - looking good peer-review journal. And it's also very surprising for me that I couldn't find any commenting papers - neither negative nor positive???

There was only "Despite experimental conformation it appears to have been ignored for three decades." comment in Howard A. Landman's paper

http://www.riverrock.org/~howard/QuantumTime4.pdf

Another citing of that paper is of the same author (David Apsel) about using this effect for pulsars:

http://arxiv.org/abs/gr-qc/0104025

Edited February 7, 2010 by Duda Jarek

[swansont]

Perhaps papers citing him aren't the way to go. Have there been papers that reconcile the lifetime with the effects of special relativity? It could be that later, better experiments proved to have better agreement with SR.

[Duda Jarek]

Why SR? Both gravitomagnetism and 'the default theory' of relativity are Lorentz invariant.

The question is if electromagnetism and gravity are so qualitatively different? How to cope it with expected unification theories? What about different intristic curvature problems, like renormalization?

[ajb]

I was not aware of any "electromagnetic time dilation". Can you give a reference that calculates such an effect?

 

To me on one hand it seems natural to expect such a thing. The presence of an external background field means no true inertial frames. This in turn I expect to be very much related to time dilation effects.

 

But then I wonder if the linearity of Maxwell's equations comes into play? There is no self-interactions here.

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Merged post follows:

Consecutive posts merged

I found this paper

 

Relativistic time dilation in an external field.

J.W. van Holten, (NIKHEF, Amsterdam) . NIKHEF-H-91-05, Mar 1991. 14pp.

 

van Holten shows that time dilation is a dynamical effect. I wonder if this is the answer to the muon life-times?

 

I think that van Holten's work tell us that in general it is not just charge and mass that contribute to the energy of a particle and thus other degrees of freedom will effect the time dilation.

Edited February 7, 2010 by ajb
Consecutive posts merged.

[Duda Jarek]

I couldn't download the paper, but still if time dilation would correspond e.g. just to acceleration, it would suggest that there is nothing so special about gravity to make it completely qualitatively different than electromagnetism, is there?

[ajb]

I couldn't download the paper, but still if time dilation would correspond e.g. just to acceleration, it would suggest that electromagnetism and gravity should behave qualitatively similarly, doesn't it?

 

As background fields maybe.

 

the paper can be found at

 

http://ccdb4fs.kek.jp/cgi-bin/img_index?9107099

[Duda Jarek]

Ohh .. I believe they are much more than only a background fields - look at the Gauss law - it sums charges inside - charges which are almost pointwise - so we can almost define such electron as near pointwise topological singularity of electric field ... maybe particles are just such special local solutions of some field ... for example spin is often defined that quantum phase makes something like that around:

http://demonstrations.wolfram.com/SeparationOfTopologicalSingularities/

[ajb]

In van Holten's analysis he simply assumes static background fields, that's all I meant really.

 

Anyway, good luck with your thoughts.

[Duda Jarek]

I just don't like the picture that the field is one thing and particles something completely different - abstract beings, which somehow can influence the field ... while they can be just built of the same field as some special local solutions - for example topological singularites, which we see in many fields.

So how do You imagine particles?

 

There appears also question - if particles have some internal structure, is it affected by fields?

Can they change a bit its properties like mass, charge, magnetic moment? It also could look like time dilation ...

Thanks for the paper.

[Howard Landman]

First I would like to thank Jarek for directing me to this discussion.

 

The latest version (1.2) of my paper is at http://www.riverrock.org/~howard/QuantumTime12.pdf (or .tex).

 

I disagree with the notion that time dilation is inherently an effect of motion. As I show, the stationary gravitational time dilation in GR is identical to the change in rate of phase oscillation in QM for stationary solutions to the Schrodinger equation, so it is entirely possible to discuss TD in stationary or static contexts, and in fact easier to see the deep link between GR and QM in that way. In fact gravitational time dilation can be derived from Newtonian mechanics and the de Broglie relation, and so can be viewed as fundamentally quantum-mechanical in nature. Special relativity and the Maxwell equations really have nothing to do with it. (They do, of course, have a lot to do with EM TD.)

[ajb]

I just don't like the picture that the field is one thing and particles something completely different...

 

Of course I understand this reservation. However, it can be useful to consider certain fields in certain circumstances as backgrounds. For example the calculation of gauge anomalies does not require you to quantise the gauge fields. Semiclassical gravity is another area where one thinks of quantising only some of the fields, the gravitational field remains classical.

 

So how do You imagine particles?

 

Particles are either a classical notion or a perturbative quantum one. It depends on what I want to think about as to how I think about them.

 

There appears also question - if particles have some internal structure, is it affected by fields?

 

If they are fundamental particles they don't have any internal structure. If they are composites then they could be affected I presume.

 

Can they change a bit its properties like mass, charge, magnetic moment? It also could look like time dilation ...

 

I think they could change the properties, but that could depend on how you want to define these properties.

 

I think we would need to look as specific models and properties here to say much more.

[Duda Jarek]

Ok - You say perturbative, but forgot to add: approximation ...

What about nonpertubative picture - in all of these theories time is continuous - when e.g. particle decays, it's not that we have one particle in the first moment and then there is a magical 'pooof' and we have two particles -physics don't like rapid changes and so especially such discontinuities - it would make this process smooth - continuous transformation from one particle into two...

What is perturbative expansion is considering different scenarios in some probability distribution.

 

Particles are either a classical notion or a perturbative quantum one. It depends on what I want to think about as to how I think about them.

If they are fundamental particles they don't have any internal structure. If they are composites then they could be affected I presume.

If they are not made of the field - so 'where' are they?

It would suggest that they 'live' parallelly to the field (?) - so how can they affect it? Why does EM field 'cares' about them?

In QFT they are excitations of harmonic potential well - so still they have some momentum structure and so after Fourier transform - some spatial structure, don't they?

If they really don't have any internal structure - are they 'pointwise'? Have infinite density? So e.g. electric field goes to infinity near them?

 

Quantum mechanics is used as a magical cape protecting from inconvenient questions ...

... but there are also nonperturbative field theories - deterministic (!) mechanics of density functionals - governed by concrete Euler-Lagrange equations ...

[ajb]

I do not have an understanding of particles in quantum field theory outside of perturbation theory.

[Howard Landman]

OK, I've read van Holten's 1991 and 1993 papers. His theory gets the same time dilation as mine (and Apsel's), since the equations in both papers essentially say deltaE/E = deltaT/T, which is the right formula at least for deltaE << E. (Not surprising: it's the only answer consistent with h nu = E = mc^2.) The really odd thing is that, despite him commenting absolutely correctly that "It is quite clear from this formula, that any quantity which contributes to the energy E in an observable way, also contributes to the time dilation", he seems completely fixated on strong external fields and completely blind to the possibility of dilation by a field-free potential. To see how silly this is, he gives an example of a spin-down muon in a magnetic field of 5 GT, when the same energy shift (and hence dilation) can be caused by putting the muon in an electric potential of a few kV. It's a lot easier to generate a potential of a few kV than a field of a few billion Tesla.

 

The nice thing of course is that this makes the theory testable with "educational" grade equipment. Some of the first experiments I proposed involved things like 25 ton toroidal NdFeB permanent magnets. My latest require under US$5K of total equipment, and I got a tour of the physics storage room at CSU this week and practically everything I need is already there. So I plan to run experiments starting in a few weeks. After a year of theorizing, it feels good to be putting the question to nature, who will tell me whether I am smoking crack, in line for a Nobel prize, or more likely, somewhere on the long continuum in between with a lot of work still ahead of me.

Edited February 18, 2010 by Howard Landman
fix minor typo

[Howard Landman]

On June 13 I ran an indirect test of (my understanding of) quantum time dilation inside the giant Van De Graaff generator at Museum Of Science in Boston. It got a null result at up to + and - 1 MV, which seems to imply that gauge invariance with respect to electrostatic potential is valid. I still need to go through the reasoning that predicted an effect and figure out where and why it is wrong.

 

The experiment was looking for change in the charge/mass ratio of an electron at potential. Since QM tells us a change in potential gives a change in phase frequency, and the de Broglie mass-frequency formula equates frequency (in rest frame) with (rest) mass, this seemed like a reasonable thing to try. No such change was detected within the 5% or so resolution of the equipment. Since a potential of -1 MV should roughly triple the phase frequency of an electron, and tripling the mass of the electrons should have produced a huge effect, it appears that either (1) no frequency shift actually occurred, or (2) the mass-frequency formula is simply wrong in this case, or (3) something else is going on that hides the effect (e.g. perhaps the charge and mass of the electrons changed by the same amount).

 

This does not necessarily completely eliminate QTD, but it seems to imply that van Holten's view (that only fields, and not potentials, cause dilation) might be the most reasonable interpretation at this time. Even if that's not what the equations seem to say. Even if that's not at all how it works for gravity.

 

I am very proud that, with help from MOS and borrowed equipment from CSU, the entire experiment cost less than US$1000 to perform. And that includes round-trip airfare from Denver to Boston. I also want to thank Southwest Airlines for letting me hand-carry the fragile electron tube both ways, and to the TSA official with a BS in physics who recognized the device on X-ray and waved me through without opening the box.

 

I have a direct test involving muon lifetimes in the planning stages. If I can coax the TeachSpin muon detector into doing what I want, it may be feasible by late this year.

[Moontanman]

Please forgive me for being completely ignorant in this but i want to ask if the idea that antimatter is repulsive to matter gravitationally is connected with gravitomagnetism?

[ydoaPs]

Please forgive me for being completely ignorant in this but i want to ask if the idea that antimatter is repulsive to matter gravitationally is connected with gravitomagnetism?

 

That idea is wrong. Both matter and antimatter have the positive mass and are attracted gravitationally.

[Moontanman]

That idea is wrong. Both matter and antimatter have the positive mass and are attracted gravitationally.

 

Wrong or simply hasn't been experimentally confirmed but seems to be the only way it could work if curvature of space-time is how gravity is propagated? I know it is assumed that matter and anti-matter attract but there are other schools of thought and so far no one has presented real world evidence that confirms or denies it.

 

What i want to know is if the gravitomagnetic theory is correct does it lend more credibility to the theory that matter and anti-matter repel each other? The idea that anti-matter could negatively curve space is difficult to deal with but the idea that anti-matter repels matter through particle interaction is a bit easier to swallow.

[insane_alien]

What i want to know is if the gravitomagnetic theory is correct does it lend more credibility to the theory that matter and anti-matter repel each other? The idea that anti-matter could negatively curve space is difficult to deal with but the idea that anti-matter repels matter through particle interaction is a bit easier to swallow.

 

no, not really.

 

if gravitomagnetic effects are true(or untrue) gravity is still mass dependant.

 

so, two positive mass particles/objects will attract each other gravitationally and only a negative mass particle/object will repel.

 

you should remember that the null hypothesis here is that antimatter is gravitationally attracted to matter and not the other way around as you imply.

[Moontanman]

no, not really.

 

if gravitomagnetic effects are true(or untrue) gravity is still mass dependant.

 

so, two positive mass particles/objects will attract each other gravitationally and only a negative mass particle/object will repel.

 

you should remember that the null hypothesis here is that antimatter is gravitationally attracted to matter and not the other way around as you imply.

 

Ok, that is what i wanted to hear or read, I know it's the null theory but null doesn't make it right just more likely to be right but I agree that anti-matter is unlikely to have negative mass. I was just curious if the GEM would be compatible with matter/anti-matter being gravitationally repulsive and negative/positive mass.

[insane_alien]

Ok, that is what i wanted to hear or read, I know it's the null theory but null doesn't make it right just more likely to be right

 

it makes it accepted as right until proven otherwise.

 

I was just curious if the GEM would be compatible with matter/anti-matter being gravitationally repulsive and negative/positive mass.

 

well, if you have a rapidly rotating ring of matter you can create a gravitational dipole but really the dimensions, mass and velocity would need to be astronomical and it could be used to repel normal matter as well.

 

the effect tends to be drastically overpowered by standard gravitational effects though.

[Moontanman]

I once read about a system that used a cylinder of nuetronium spin at almost the speed of light. It produced a worm hole type effect, i can't remember exactly where or when.... Is this what you are referring too?

[insane_alien]

not quite, but even if it was made o neutronium it would fly apart before you goit it up to to a speed where gravitomagnetism would rival normal gravity.