Cosmological horizons, and a sceptic's view of special and general relativity

[ErkDemon]

For your perusal:

General relativity applied to an expanding universe supports two obvious sorts of curvature horizon: cosmological horizons and gravitational horizons. It might be nice if we could topologically transform one into the other, and treat both according to the same basic geometrical rules. But under GR1915, we aren't supposed to make this comparison, because a quirk of GR1915's construction forces these two sorts of horizon to have different properties.
For a cosmological horizon, objects obviously have to be capable of passing both ways through an (arbitrarily-defined) cosmological horizon surface. A CH looks rather like a gravitational event horizon (infinite redshift and so on), but it has a positive temperature: it leaks radiation. As particles move into view from behind a CH, it might seem to an observer that that their (eventual) arrival in front of the horizon surface was acausal – in observerspace coordinates, particles moving towards us through a CH would be described as appearing “from nowhere” (from spatial coordinates that don't exist in our observerspace map), or from time-coordinates that we might map to the infinite future. There's obviously no genuinely acausal behaviour or actual reverse causality going on here, but in observerspace coordinates these particles seem to appear outside the horizon in a way that isn't completely predictable from information available on our side of the surface, and in a “conserved” observerspace description we'd tend to describe them as appearing as the result of pair-production events, with the “observerspace-legal” part of their paths describing a particle moving towards us, and the earlier “observerspace-illegal” part appearing in the description as an a time-reversed anti-particle travelling away from the apparent creation point and leading back towards the horizon.

So cosmological horizons show the classical or semiclassical equivalent of what we'd now recognise as “Hawking radiation”-type behaviour. They seem to be what we'd now refer to as “acoustic” horizons, and to show old-fashioned “acoustic” indirect-radiation effects.

GR1915's “BLACK HOLES”

When GR1915 was originally developed, Einstein didn't seem to make this comparison between gravitational and cosmological horizons, presumably because he originally developed GR in the context of an infinite, static universe. If he had made this comparison (perhaps by turning the observerspace description of a Friedman universe inside out, so that the cosmological horizon looks like a gravitational horizon “censoring” a presumed “Big Bang” singularity), he might have decided that, topologically, if cosmological horizons gave off indirect radiation, then gravitational horizons would have to as well. But instead of stepping outside the observerspace description to allow the presence of not-directly visible variables to affect visible data indirectly, Einstein seemed to construct GR1915 within observerspace, and by using the presumption that events have to not only be causal but must also be seen to be causal, “proved” that (according to GR1915) no information could possibly pass outwards through an event horizon on principle.

Although Einstein himself was sceptical about GR1915's predictions of a perfect causal cutoff at a black hole's event horizon, 1950's theorists (notably John Wheeler) seized upon these new perfectly non-radiating objects as great things to study, and black holes became a major research subject in the 1960's. At this point (before the prediction of Hawking radiation in the 1970's) we “knew” that comparing the two sorts of horizon was a dumb idea, because one obviously radiated and one provably didn't. They were obviously two separate cases: black holes were new and interesting and CH's weren't, and as a result we got enraptured by black holes, and forgot to look at what the less glamorous CH's might have been able to tell us about physics.

COSMOLOGICAL HORIZONS vs. SPECIAL RELATIVITY

The problem that a cosmological horizon poses for GR1915 is that a CH seems to operate according to the rules of an acoustic metric, and since any point in the universe can be considered as lying on a cosmological horizon for someone, this kinda leads us to the conclusion that our own physics ought to be operating according to the physics of an acoustic metric, too.

In acoustic-metric models, the acceleration or velocity of a particle past its neighbours warps the lightbeam geometry of a region, so that an object previously behind a cosmological horizon that gets accelerated towards us creates a local offset in the speed of light around it, and a section of the the “mathematical” surface for the CH then jumps discontinously from in front of the object to behind it. If we didn't include these effects in our description, we might conclude that the object's sudden appearance corresponds to the object jumping discontinuously from behind the (supposedly static) horizon to in front of it. So acoustic metrics support the appearance of discontinuous quantum-tunnelling effects (within observerspace), from non-QM principles.

According to general arguments, both of these warpage effects ought to exist for real. General relativity (and Mach's Principle) require acceleration effects to be mutual, so that when a forcibly-accelerated body feels an apparent gravitational field associated with the relative acceleration of the background universe, other observers in that background should also feel a (correspondingly smaller) effect due to the relative acceleration of the object (Einstein, Princeton lectures, 1921). Under GR, forcibly-accelerated bodies warp spacetime and drag light along with them, and this can be described as an accelerational “frame-dragging” effect. But acoustic metrics also seem to include a velocity-based local light-dragging effect ... something comparable shows up under GR1915 for objects with significant gravity that move or rotate (“gravitomagnetic” field-effects, such as frame-dragging around a rotating black hole), but acoustic metrics require these effects to apply to all objects, regardless of whether their conventional gravitational field is reckoned to be significant or not, as long as we can get sufficiently close.
Experiment seems to confirm the existence of velocity-based light-dragging effects (Fizeau experiment), so the “acoustic metric” arguments seem to tie in nicely with known principles, and also seem to correspond reasonably well to the available evidence.

The problem here (for SR) is that Einstein's special theory of relativity was founded on the simplifying assumption that these sorts of lightspeed dependencies didn't exist. That assumption led to Minkowski's non-acoustic metric, and it uniquely defined a set of conventions and definitions and equations of motion that were then in place throughout the C20th, and were partially adopted by general relativity (assuming a reduction to SR made Einstein's job of developing his general theory slightly easier than starting form scratch).

Special relativity's relationships support the idea that GR1915's predictions about non-radiating gravitational horizons can't possibly be wrong, so if we want a simple mechanism for indirect radiation through gravitational horizons (contra GR1915), it seems that we also have to change the basic relationships of SR. We'd need a new set of basic equations that were “redder” than the SR versions. But since textbooks tell us that SR's correctness is non-negotiable, we haven't been exploring this possibility.

ACOUSTIC METRICS, AGAIN

Acoustic metrics only started to be studied seriously in the 1990s (perhaps a century later than they should have been), as a potential way of modelling quantum effects around black holes, and as a potential route towards a future theory of quantum gravity. There's quite a lot of research going on in this field (modelling semiclassical Hawking radiation across acoustic horizons in Bose-Einstein condensate or in slowed-light experiments, that sort of thing), but what the QG guys probably won't tell you is that if fundamental physics really does correspond to an acoustic metric, once again, the basic relationships would seem to have to be different to those of special relativity.

The problem with special relativity (and with Minkowski spacetime) is that it's just too mathematically perfect ... or rather, it's a solution that perfectly answers the wrong question. It's the relativistic solution to physics in flat spacetime, and assumes that moving bodies don't in any way affect the underlying behaviour of light, which, of course, they do – if gravitomagnetism was fundamental, then there'd actually be no such thing as the physics of flat spacetime, because spacetime would only be truly flat if there was no interesting physics going on there. The characteristics of the curvature would describe the physics. For a more realistic model we'd have to allow the initial Minkowski metric to be warped and distorted by the presence and motion of particles, but since the distances within Minkowski spacetime define the energy and momentum relationships of SR, if we allow velocity-warpage within this metric, the basic relativistic relationships seem to have to change, to fit the new geometry -- if the additional; distortion of a “moving” particle's gravity-well passing its “stationary” neighbours creates an effective increase in the amount of space in a region, then the wavelengths of light given off by that particle have to be correspondingly longer to fit the available space.
So once again, we're looking at relationships that would have to be “redder” than those of special relativity, and if we change the basic Doppler shift relationships used by SR, we also change the nominal momentum of light given off by a moving object, so (by E=mc^2), we'd also be changing the nominal velocity-based relationships for the energy and momentum of a moving body.

These sorts of issues also seem to show up in conventional GR when we look at the effects of a moving gravitational body on nearby light, but we're trained not to pay too much attention to questions that'd seem to undermine the basis of SR, so we tend not to follow them up.

EXPERIMENTAL TESTING

Now at this point, an SR-trained physicist is liable to interject that the idea of SR being fundamentally wrong is obvious rubbish, because we have stacks of experimental evidence collected over the last century that prove that SR is great, and nothing that seems to disagree with it. But the actual situation is slightly more complex:-
Special relativity's predictions are “redder and shorter” (by a Lorentz factor) that those of a reference set of predictions that we refer to as “classical theory”, and when we test these relationships in real life, and find that in fact they are significantly redder and shorter than CT says, we say that this proves that our new SR effects are real, and that SR's new predictions are therefore backed up by hard experimental data. But for our acoustic metrics, the relationships would be even redder and shorter than SR, and that's not a possibility that SR experimenters were forewarned to look out for and evaluate. So, when some experiments found more of a redshift than SR predicted, they still got classed as successfully verifying special relativity. Because of this, if we're given a choice between SR and a “redder” relativistic model, we can't easily tell these apart by using the existing experimental writeups. We'd have to do a lot of these experiments over again, while looking out for slightly different things during calibration, etc.

If our deviation from special relativity is “Lorentzlike” (which it'd seem to have to be in order to obey the principle of relativity), then we'd still get the “good bits” of special relativity like E=mc^2 and momenergy, as long as we remembered to scale everything in the new model by the same Lorentzlike correction factor, 1/ [1- vv/cc]^x (where the exponent “x” hasn't yet been defined).

The next step would be to try to work out exactly how big this expected gravitomagnetic deviation from SR should be, and what figure we need to write in for the exponent.

POLITICS, PSYCHOLOGY, AND UNWANTED SOLUTIONS

Now, from the above, it seems that we have a simple way forward. It would seem that there's no psychological problem associated with moving forward from special relativity to an acoustic metric model that treats spacetime curvature as the basic mechanism for mechanics, reminiscent of the schemes imagined by Clifford and Wheeler. We could say:
“Special relativity never claimed to be valid for warped spacetime or for effects due to the presence of particulate matter. It was always a solution based on the idea that a region contains a perfect vacuum, and never claimed to be able to handle gravity or particulate effects. Einstein freely acknowledged this shortcoming (the 'consistency problem'). Rather, special relativity describes the physics of flat spacetime upon which this new Lorentzlike factor, which describes the local particulate gravitomagnetic effects missing from SR, can be overlaid. Special relativity isn't wrong, it can be considered as the underlying geometrical foundation of this newer gravitomagnetically-based theory, which can then be thought of as a logical extension to special relativity. All we have to do to “correct” SR is put in the missing Lorentzlike gravitomagnetic effect.”

And if it's that simple, one might ask why this hasn't been done already.
Why don't we have a revised general theory based on a different set of gravitomagnetic assumptions that allows us to “flip” between gravitational and cosmological horizons, solve GR's incompatibility with QM and eliminate the black hole information paradox?

Well, it's partly because of the nature of the solution that we get with this approach.
When we try to work out what this hypothetical solution would have to be, we find that there only seem to be one potential relativistic solution that fits the bill, and that mathematical solution might represent a nightmare for the physics community. If it was correct, it'd literally have some of these guys deciding that their entire careers had been worthless, and topping themselves.

Here's why this solution is “unthinkable”.
When we look at our hypothetical Lorentzlike GM factor, the undefined exponent allows a continuous, infinite range of possible solutions, all of which satisfy the basic principle of relativity, with SR being a point on that line that represent a unique zero-curvature solution. We require a positive-curvature solution, so all points on the line to one side of the SR solution (solutions “bluer” then SR) can be discarded. Total frame-dragging (at the surface of a “moving” black hole) suggests that the new equations (applied to black holes) might have to be exactly one Lorentz-factor “click” redder than SR, and if we required the same equations of motion to work for all objects irrespective of surface gravity, then perhaps we might want that modification to apply to “little” things like electrons, too.
A stronger argument seems to be given by our requirement that gravitational horizons need to give off indirect radiation. Applying a “Lorentzlike” factor and tinkering with the exponent, if we redden SR's velocity-shift predictions by anything less than one full additional Lorentz factor, classical indirect radiation doesn't work, whereas if we redden them by any more than one full Lorentz factor, the equations go weird and scary. So it seems that if we want gravitomagnetism to solve the GR horizon problem, our basic SR equations of motion need to be reddened by exactly one additional Lorentz factor, to take into account the missing velocity-curvature effects.

Now, here comes the nightmare. If we redden SR by exactly one additional Lorentz factor to get our advanced Twenty-First Century “gravitomagnetic” theory of relativity, a truly general theory of relativity that applies the curved-spacetime idea “all the way down” to the particle level and reconciles GR's geometrical approach with quantum theory ... then it turns out that this process turns special relativity's longitudinal “relativistic Doppler” equation
f'/f = SQRT[ (c-v)/(c+v) ]
into
f'/f = (c-v)/c

, and turns
p=mv [gamma]
back into
p=mv

I really wish this wasn't the case, and I really wish that the gravitomagnetic solution that's missing from the textbooks would have turned out to be something new and novel and glamorous and easier to sell, but unfortunately I can't do anything to change the math. That's just how it comes out. So if this result is correct, parts of our C21st century theory of quantum gravity turn out to be energetically-indistinguishable from Eighteenth Century emission theory, and some of the modifications that SR made to Newtonian theory have to be struck out as mistakes based on the inappropriate introduction of the “flat-spacetime” hypothesis. It'd mean that a lot of the “improvements” made by SR had actually made the numbers worse.

This isn't an outcome that most physicists would find acceptable, not because it's mathematically ugly (some of the relationships are simpler than SR), or because it's overly complex (it is, after all, the minimal reduction to Newtonian mechanics), but because it's too damned simple.

If it's right, it makes the last century of searching for increasingly complex “composite” models and mathematical solutions look dumb. Physics teachers and lecturers have spent most of the last century telling bemused schoolkids and students that they have to suspend disbelief and accept special relativity because that's simply how nature operates, so if they were to find that actually it's not how physics operates, and that a lot of the complications added by special relativity only served to make the final numerical predictions less accurate ... well, that's simply not an acceptable state of affairs.

So currently we seem to be a bit stuck. There seems to be a possible way forward, but we can't explore it (or test it), because if it's right it'd make us look silly, and if there's something that physicists don't like, it's looking silly. So, for the last few decades we've been desperately trying to examine every other possible way of solving the black hole information paradox, in the hope that something unexpected would turn up that would magically turn out to fix up general relativity without our having to go back and rebuild it around different rules, without special relativity as a foundation stone. And so far that alternative solution hasn't appeared.


PROGRESS

The quantum gravity guys have found a way to quietly make some progress while skirting around the SR-incompatibility issue. They're pressing ahead with studies of acoustic metrics, but they aren't publicly discussing the non-SR implications of their work, and they're not describing it as a literal physical model, only as an “analogue” or a “toy model” for quantum gravity. Some of them might honestly not know the non-SR implications. Others might suspect but be keeping damned quiet about it.

And that's where we seem to be right now. The “acoustic metric” and “analogue gravity” researchers are moving forwards and filling in as many gaps as they can, but their work seems to be able to proceed partly because the wider physics community doesn't understand the implications of what they're doing, or what the ultimate conclusion of that work is likely to be. The research is conducted in plain view, but as far as the converging conclusions of that work is concerned, and how it affects the status of special relativity, it's almost a form of “stealth research”. Don't ask, don't tell.

But at some point, I think that part of the QG research community is going to hit a crisis where they can't progress any further without somebody actually coming out and saying that if all the preceding work is correct, it looks like special relativity is basically wrong.

That'll be interesting to watch.

Eric

[Wangler]

This looks very interesting, but the underlying concepts are certainly over my head.

The acoustics slant seems worth a look, at least.

Keith

[sol invictus]

Cosmological horizons are a standard feature in general relativity, and GR reduces to special relativity. Furthermore acceleration horizons exist even in flat Minkowski space. Not only is there no conflict between special relativity and such horizons, SR predicts their existence.

I read your post twice, and I cannot tell what it is you think the conflict is.

And this part
The quantum gravity guys have found a way to quietly make some progress while skirting around the SR-incompatibility issue. They're pressing ahead with studies of acoustic metrics, but they aren't publicly discussing the non-SR implications of their work, and they're not describing it as a literal physical model, only as an “analogue” or a “toy model” for quantum gravity. Some of them might honestly not know the non-SR implications. Others might suspect but be keeping damned quiet about it.

And that's where we seem to be right now. The “acoustic metric” and “analogue gravity” researchers are moving forwards and filling in as many gaps as they can, but their work seems to be able to proceed partly because the wider physics community doesn't understand the implications of what they're doing, or what the ultimate conclusion of that work is likely to be. The research is conducted in plain view, but as far as the converging conclusions of that work is concerned, and how it affects the status of special relativity, it's almost a form of “stealth research”. Don't ask, don't tell.

is classic woo conspiracy theory nonsense (to be blunt). There is no "stealth" research. Many people have proposed alternatives to SR (and been wrong). Anyone that showed that SR is wrong would instantly become one of the most famous physicists in the world, which is a strong motivation that drives many people to try.

Woos and crackpots often have this delusion - they don't understand that science is all about looking for cracks in the dominant theories, instead they think it's a conspiracy to suppress new ideas (typically theirs). And yet apart from the rare times where there's a truly new phenomenon which hasn't been explained yet, looking for problems in the dominant paradigm is essentially all there is to science - testing the existing theories and looking for holes in them. It's the diametrical opposite of what most cranks think it is.

[Dancing David]

This was all I was able to find on the web in a short shearch, there were some papers I could find as well.
Was "Observersapce' on wikipedia

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


From the OP essay

The problem with special relativity (and with Minkowski spacetime) is that it's just too mathematically perfect ... or rather, it's a solution that perfectly answers the wrong question. It's the relativistic solution to physics in flat spacetime, and assumes that moving bodies don't in any way affect the underlying behaviour of light, which, of course, they do – if gravitomagnetism was fundamental, then there'd actually be no such thing as the physics of flat spacetime, because spacetime would only be truly flat if there was no interesting physics going on there.



So once again, we're looking at relationships that would have to be “redder” than those of special relativity, and if we change the basic Doppler shift relationships used by SR, we also change the nominal momentum of light given off by a moving object, so (by E=mc^2), we'd also be changing the nominal velocity-based relationships for the energy and momentum of a moving body.



Now, here comes the nightmare. If we redden SR by exactly one additional Lorentz factor to get our advanced Twenty-First Century “gravitomagnetic” theory of relativity, a truly general theory of relativity that applies the curved-spacetime idea “all the way down” to the particle level and reconciles GR's geometrical approach with quantum theory ... then it turns out that this process turns special relativity's longitudinal “relativistic Doppler” equation
f'/f = SQRT[ (c-v)/(c+v) ]
into
f'/f = (c-v)/c
, and turns
p=mv [gamma]
back into
p=mv
I really wish this wasn't the case, and I really wish that the gravitomagnetic solution that's missing from the textbooks would have turned out to be something new and novel and glamorous and easier to sell, but unfortunately I can't do anything to change the math. That's just how it comes out. So if this result is correct, parts of our C21st century theory of quantum gravity turn out to be energetically-indistinguishable from Eighteenth Century emission theory, and some of the modifications that SR made to Newtonian theory have to be struck out as mistakes based on the inappropriate introduction of the “flat-spacetime” hypothesis. It'd mean that a lot of the “improvements” made by SR had actually made the numbers worse.



So, hmm, weeell, I would say that it is a Nobel Prize for sure, it is was correct.

[sol invictus]

So, hmm, weeell, I would say that it is a Nobel Prize for sure, it is was correct.

There an infinite number of wrong ideas that, if they were right, would win a Nobel.

Although the world might implode under the weight of its own logical inconsistency before the prize could be awarded....

[ErkDemon]

So, hmm, weeell, I would say that it is a Nobel Prize for sure, it is was correct.

Well, on the plus side, it //should// be testable with current technology. If you point a detector at a particle beam at 90 degrees (measured in the lab frame), special relativity will predict a Lorentz redshift, while this thing will predict a Lorentz-squared redshift (i.e. in most experiments, roughly twice as much).

But unfortunately, psychological factors also come into play when we set up and assess data. This experiment was actually done in 1979 (Zeitschrift fur Physik A 289 151-155), and funnily enough, it did report roughly twice the redshift predicted by SR. But the experimenters decided that since that result couldn't be right, the detector must have been accidentally misaligned by about half a degree, and they then used statistics to demonstrate that, bearing in mind this retrospectively-downgraded estimate of the accuracy of where the detector was pointing, this result supported special relativity. Hmm.
There didn't seem to be any further published followups confirming that the detector angle really was off (they inferred this from the excess redshift), and there doesn't seem to be any record of anyone else successfully doing this test since. One does sometimes see cryptic references to this sort of "true transverse" redshift test being difficult and unreliable (due to its high sensitivity to any detector misalignments). These angular errors ought to be easy to verify and correct (bolt the detector and mirrors on a turntable and take two sets of transverse readings exactly 180 degrees apart, at "90+unknownerror" and "90-unknownerror"), but nobody seems to have done it.
This naturally leaves me wondering if perhaps this sort of test is considered "difficult" simply because people can't persuade it to produce redshifts in a range that they consider to be sensible ...

There are quite a few other "transverse" redshift tests that are actually longitudinal tests, and are easier to set up - they measure the forward and rearward frequencies and combine them with the original frequency to get a characteristic triplet of ratios that should let us derive a “transverse” component and rule out certain shift relationships.
But again, unfortunately, the experimenters doing these tests usually only have a remit to compare SR's transverse Lorentz result with classical theory's "no-shift" result, which means that they're quite entitled to tweak the gear to get rid of any excess redshifts outside this range, without having done anything wrong. :( The test theory that they work to tends not to include a Lorentz-squared redshift as a possible result whose possibility needs to be taken into account. The more sophisticated and accurate these tests are, the more difficult it is to second-guess all the little secondary things that an experimenter might have done, which wouldn't have affected the comparison that they set out to do, but might have made their data unsuitable for evaluating SR against "out-of-range" predictions like this.

The one longitudinal test that would seem to produce a simple reinterpretable result is the ancient Ives-Stilwell test of 1938, which seems to confirm SR and rule out the suggested alternative. But then again, that test was a "mk1" test, had a few quirks (a mysteriously missing spectral line), and later experimenters have asked whether it could really have been as accurate as claimed with the equipment used. I don't think anyone's claimed to have managed that accuracy again with that sort of gear (the result was later confirmed with more advanced gear and more complex setups that are correspondingly more difficult and dangerous to reanalyse for correspondence with models not explicitly on the experimenters' checklist).

So the only two experiments that seem simple enough for a confident reanalysis have both had question marks raised over their accuracy, and both seem to indicate different results. If the 1938 test was “dodgy” and the 1979 test was “good”, then it looks as if this thing might be right and SR wrong. In that scenario, SR would have been experimentally disproved nearly thirty years ago, without anyone noticing! :)

OTOH, if the 1938 test was “good” and the 1979 test was “dodgy”, then that supports the SR relationships and explains away the later result that suggests otherwise.

OTOOH, maybe both of them were dodgy! ;)

(raises arms in a “who knows?” gesture)

[ErkDemon]

The acoustics slant seems worth a look, at least.

For anyone who wants a general intro to the subject (sans any possible implications for SR), there's a mostly-readable intro on the Wikipedia "acoustic metric" page
http://en.wikipedia.org/wiki/Acoustic_metric

and AFAIK, the definitive review article is probably still the 2005 paper by Barcelo, Liberati and Visser "Analog Gravity", which references 400-odd sources
http://arxiv.org/abs/gr-qc/0505065
(, which I'm assuming you already know about, from the topic of your post!)

Visser's paper that helped set the ball rolling was
http://arxiv.org/abs/gr-qc/9712010

Yaaay! Fifteen posts! I can post URLs! :) :) :)

[sol invictus]

Well, on the plus side, it //should// be testable with current technology. If you point a detector at a particle beam at 90 degrees (measured in the lab frame), special relativity will predict a Lorentz redshift, while this thing will predict a Lorentz-squared redshift (i.e. in most experiments, roughly twice as much).

Huh? 90 degrees to what?

But unfortunately, psychological factors also come into play when we set up and assess data. This experiment was actually done in 1979 (Zeitschrift fur Physik A 289 151-155), and funnily enough, it did report roughly twice the redshift predicted by SR.

Are you aware that there are dozens of particle physics experiments around the world, conducted in accelerators pointed in all sorts of different directions (most are circular, actually), which test time dilation and Lorentz invariance generally with literally trillions of events, to the point that some parameters (which are crucially dependent on the correctness of SR) are measured to 12 significant figures?

Just a question.....

[ErkDemon]

Huh? 90 degrees to what?

... at 90 degrees to the beam path. The beam can be represented as a line, the detector is aimed at 90 degrees to that line. If the beam's too wide, mask off the parts that you don't want the detector to register.


Are you aware that there are dozens of particle physics experiments around the world, conducted in accelerators pointed in all sorts of different directions (most are circular, actually), which test time dilation and Lorentz invariance generally with literally trillions of events, to the point that some parameters (which are crucially dependent on the correctness of SR) are measured to 12 significant figures?
Just a question.....

Yes, I am, thanks.

And presumably you're aware that for a particle moving in a straight line at constant speed, with a specified rest frame decay time, energy and momentum, the position at which it decays is precisely the same regardless of whether you use NM or SR?
For a continuous range of potential theories of relativity fading from SR to NM and out the other side, separated by Lorentzlike terms (as briefly described), they'll all predict exactly the same decay point. It doesn't matter whether you then conduct an experiment to measure this position to 12 significant figures or to twelve hundred. It's the same point. We just interpret why the particle chose to decay at that point differently under the different models. In this situation the significance of that decay point is interpretational. It means something under SR, and it means something else under other theories. But the fact that the SR interpretation is unique to SR doesn't mean that the unambiguous physical prediction of where the thing decays in the tube unique to SR. It aint. For a simple constant-velocity straightline path, we can't isolate an SR time-dilation effect on principle, because if we really could say unambiguously that a given "coasting" particle has a certain amount of velocity-based time dilation, that'd amount to being able to assign it a particular agreed speed, which would mean that there'd have to be a particular agreed frame for the propagation of light, which in turn would break the principle of relativity as applied to light and break SR.

This sort of thing, touched upon:
Taylor and Wheeler "Spacetime Physics", 2nd ed, ISBN 0716723271 p.76-77, box 3-4 "Does a moving clock really 'run slow'? "

This is where the particle accerator guy normally jumps in and says, "Ah, but that's for a straight line path! But we have circular particle storage rings where the slowed ageing rate of the particles is unambigous! The particle's decay time is so short that it couldn't perform a complete circuit at less than the speed of light, and yet we can time the particles doing a round trip, and verify that they are moving slower than background lightspeed, and yet the particles manage to make one or more complete circuits! They really are physically time dilated! Nobody's ever come up with an alternative explanation for how this could happen without SR!"

And, of course, an alternative explanation is available, and was briefly published by the Harwell group (before it got squelched): A circling particle feels gee-forces, and if we apply the equivalence principle, and and invoke the presence of an apparent centrifugal field, then the gravitational time dilation effect associated with that field seems to give the right value for the amount of time dilation in the particle, without our knowing anything about special relativity. Phys Rev Lett 4 165-166 (1960). If we apply the equivalence principle, SR's velocity-based time dilation effect is redundant. The Harwell group paper got the alternative explanation into print by implying that the SR and EP descriptions might be dual. That seems to have caused a bit of a stir, because then people realised that actually the two explanations probably couldn't be dual, which implied that either the EP or SR (or both!) had to give way. But if the SR explanation wasn't right, then perhaps GR1915 wasn't right either, and without GR1915 we didn't have an established framework to apply the EP, and we lost both SR and GR1915.

So Alfred Schild's rebuttal paper, which came out pretty promptly afterwards, declared that since SR couldn't[I] be wrong, we had instead to suspend the equivalence principle whenever it appeared to be about to conflict with SR: therefore, the equivalence principle Must Not Be Applied to centrifuged clocks.

That was 1960, and I don't know of the Harwell argument being mentioned in any textbook or mainstream physics journal since. It just disappeared off the radar, and if think that if the PRL referees had realised that it was going to be so controversial, they might never have let it get into print in the first place.


Um. Okay, I've rattled on too much. But to answer your actual question, yes, I've looked into particle accelerator experiments.
I've also asked a few particle physics guys. Unfortunately they weren't much help. They gave me a lot of compelling arguments based on things they said were unique to SR (which weren't) and high-precision results which were almost irrelevant to my problem, and each time we went through a tedious cycle where they'd tell me something else impressive and I'd have to politely correct them before they told be the next impressive thing that wasn't quite true either. Eventually they'd get to something sufficiently technical where I wouldn't be able to tell if what they were telling me was correct or not ... and I'd be asked to take their word on it as a professional.
But after someone's told you wrong things about five or six times in a row (and asked you to take their word for it), on the simpler stuff, one gets a bit reluctant to suddenly take their word for things that are more complicated.
I mean, I'm sure that the p-p guys are brilliant at designing accelerators and running them, but they don't necessarily have the background to do cross-theory analysis. Which is okay, because they don't really need to know that additional stuff in order to do their job well.

So, while I'm sure that the information needed to settle the question of which set of equations is right can (in theory) be settled by looking at existing particle accelerator data, asking the p-p guys themselves is a bit like trying to piece together a picture of a black hole's innards by collecting its outgoing Hawking radiation. Sure, the information must be buried in there somewhere, but the information that's being presented to you is so garbled and scrambled and filtered and incomplete, its difficult to know how to make sense of it. It's easy to be given [I]an answer ("Special relativity is definitely right, no doubt about it"), but its difficult to know how much faith to put in that answer if the guys giving it to you don't really know how to compare the results of SR, with, say, the results of applying Newtonian mechanics.

After I'd asked a few accelerator guys, and had the same slightly depressing experience each time, I kinda stopped asking. :(

I think that perhaps the way out of this impasse is for someone to set aside all the existing data and do a new test, some sort of updated Ives-Stilwell, and explicitly try to check whether the transverse redshift effect really does follow a Lorentz law or a Lorentz-squared law. And then, since we know that individual experiments can screw up, perhaps a few different people can try it with different hardware.

[sol invictus]

... at 90 degrees to the beam path. The beam can be represented as a line, the detector is aimed at 90 degrees to that line. If the beam's too wide, mask off the parts that you don't want the detector to register.

Essentially all particle physics are oriented that way. They are generally cylindrical, oriented along the beam path, and centered on the interaction point.

And presumably you're aware that for a particle moving in a straight line at constant speed, with a specified rest frame decay time, energy and momentum, the position at which it decays is precisely the same regardless of whether you use NM or SR?

Fundamental mistake number 1. That is totally wrong.

Consider a particle moving at v=.999c, c being the speed of light. In Newtonian (or more properly Galilean) mechanics, if its lifetime at rest is T, it will decay after traveling a distance vT = .999c T from where it was produced.

In special relativity, however, it will decay after traveling a distance gamma vT, where gamma is (1-v^2/c^2)^(-1/2). In this case, gamma=22 or so, so the particle will travel 22 times as far.

Such large (and much larger) gamma factors are routine at particle accelerators, and this effect is measured and confirmed literally billions of times every day.

[Wangler]

Sol,

Maybe Erk's confusion about the decay stems from the fact that is statement:

the position at which it decays is precisely the same.........

Is based upon a particular frame of reference?

:boggled:

[sol invictus]

Maybe Erk's confusion about the decay stems from the fact that is statement:

Is based upon a particular frame of reference?

:boggled:

Beats me.

I mean, it's true that in the rest frame of the particle it always decays in the same place regardless of whether we use Galilean or Lorentzian mechanics... but that's because it doesn't move! That's the only frame in which the statement is true, and it's completely stupid in that frame - if something is at rest at x=0, yes, it stays at x=0 until it decays. Not very interesting.

The fact is that particle physics experiments observe time dilation all the time - fast moving particles live for much longer than they would in their rest frame, and without knowing that the results of PP experiments would be completely incomprehensible.

[MattusMaximus]

The fact is that particle physics experiments observe time dilation all the time - fast moving particles live for much longer than they would in their rest frame, and without knowing that the results of PP experiments would be completely incomprehensible.


You don't even need particle accelerators to confirm time dilation. I have my students perform a table-top experiment whereby we detect muons zipping through the atmosphere which have a longer lifetime than resting muons.

[Wangler]

You don't even need particle accelerators to confirm time dilation. I have my students perform a table-top experiment whereby we detect muons zipping through the atmosphere which have a longer lifetime than resting muons.

That sounds cool! If you don't mind me asking, how is that done?

[zosima]

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

Look at the precession of the perihelion of mercury. It's very accurately measured and completely consistent with general relativity. The claim made in the article above, is that this modified factor cancels the Lorentz factor and returns us to newtonian dynamics....which means this phenomenon that couldn't be explained until general relativity and under this new theory goes back to being unexplained again.

[ErkDemon]

Essentially all particle physics are oriented that way. They are generally cylindrical, oriented along the beam path, and centered on the interaction point.

Yep, that's why I wasn't sure why you were querying “90 degrees to what?” It should have been clear from the context.


... for a particle moving in a straight line at constant speed, with a specified rest frame decay time, energy and momentum, the position at which it decays is precisely the same regardless of whether you use NM or SR ... Fundamental mistake number 1. That is totally wrong.

Nope. Go back and re-read what I said, ver-ry carefully.

For an agreed energy and momentum. Not for an agreed speed.

In your atmospheric muon case, we don't measure the speed of the muon directly. We calculate it from the energy and/or momentum, and if we do that calculation assuming SR, we get a different nominal velocity for the muon to what we'd have gotten if we'd assumed NM. What we can't do in a fair comparison is calculate a velocity by assuming one theory, and then use that velocity value to invalidate the other theory. You have to do each calculation independently.
If we call the calculated nominal velocity for the muon under special relativity “vSR”, and the corresponding nominal velocity under Newtonian theory “vNM”, then because SR allows more momentum for a given velocity than NM, by the Lorentz ratio, “vNM” will be larger than “vSR” by the Lorentz factor (where the “v” in the Lorentz factor is “vSR”).

So, how far does the muon travel before decaying, given an agreed amount of energy and/or momentum?

If we write distance = vt then the NM calculation, with its higher nominal velocity, is
distNM = (vSR × Lorentz) × t
, whereas the SR calculation uses the smaller vSR velocity, but says that the decay-time is extended by the Lorentz factor, giving
distSR = vSR × (Lorentz × t)

So, working from the uninterpreted properties available to us, energy and momentum, we find that distSR = distNM

As a result of this, in these tightly-controlled cases, with particles moving in a straight line at constant velocity in an accelerator tube with an agreed energy and momentum and an agreed start position, the position in the tube where the particles will decay will be precisely the same under special relativity as it would have been under Newtonian theory. If you want to test how well SR predicts that position, to twelve decimal places, go ahead and have fun. But if you want to assign an additional significance to those results, and use them to claim that one particular theory is better than another, you need to know that the SR predictions will be exactly the same as the predictions we'd have gotten using NM.

The predicted decay point will also be precisely the same for any one of an infinite number of other potential theories of relativity based around equations that diverge from SR by a Lorentzlike factor. The NM and SR solutions are just two point-solutions on this line, but all these solutions give the same prediction for this situation.

[ErkDemon]

Sol,

Maybe Erk's confusion about the decay stems from the fact that is statement:
...
Is based upon a particular frame of reference?
:boggled:

No, see post #16. my statement about decay position is correct. If the constant-velocity particle particle decays at a particular position in the straight accelerator tube, you can mark that position on the side of the tube with a physical chalk-mark, if you like. I'm not playing any games here with interpreted coordinate systems. It's a straightforward match.

[sol invictus]

Nope. Go back and re-read what I said, ver-ry carefully.

No need, because what you're saying here is just as wrong, only in an even more basic way.

For an agreed energy and momentum. Not for an agreed speed.

That's impossible - the dispersion relations aren't the same.

Look: if we agree on the momentum (and the rest mass), the energy is determined. You cannot specify them independently, and the equation that determines them in SR isn't the same as the equation that determines them in NM. So we cannot agree on the energy and the momentum in SR and NM at the same time - that's a nonsensical requirement.

Since this is evidently a remedial class, let's make this explicit. Suppose we have a particle of rest mass m. Both SR and NM will agree on m, because SR reduces to NM at low velocities:

NM: $E = p^2/(2m) = mv^2/2$

SR: $E = \sqrt{m^2 c^4 + p^2 c^2} = m c^2 + p^2/(2 m) + O(p^4) = m c^2 + m v^2/2 + O(v^4)$

Since the mc^2 term is a constant, both agree on how the energy E varies with momentum p, so long as p is small compared to m/c. However once p is large compared to m/c they disagree.

So we cannot specify both E and p. Instead, the only possibility is to specify one of E, p, or the velocity v as I did in my example above. If we specify either E or v we see again that your statement - that the particles will decay at the same location - is false.

If we agree on the momentum, but not on the velocity or the energy, then it is true that the positions will be the same. That is not what you said in either post and regardless it is irrelevant to my point, because it is the energy that is measured in particle detector calorimeters. In some cases the velocity is measured directly as well - for example at B factories - and sometimes the momentum is measured too (using the curved bubble chamber tracks charged particles make in magnetic fields).

When more than one of E, p, v is measured we can directly check which of the above two formulas is correct (in addition to more indirect checks like the lifetime). All of such measurements are consistent with SR, none are consistent with NM, and as I said, there are astronomical numbers of them - at least trillions of independent measurements.

[ErkDemon]

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

Look at the precession of the perihelion of mercury. It's very accurately measured and completely consistent with general relativity. The claim made in the article above, is that this modified factor cancels the Lorentz factor and returns us to newtonian dynamics....which means this phenomenon that couldn't be explained until general relativity and under this new theory goes back to being unexplained again.

No, that result carries over. The extra precession of Mercury's perihelion (and the extra light-bending in Eddington's test) are explained by curvature of the time coordinates as well as the spatial ones. Various guys in the C19th were already trying to model Newtonian gravity as spatial curvature, but their attempts failed because they didn't realise that they should have been applying curvature in four dimensions rather than three.

The breakthrough came when Einstein recognised that gravitational shifts (which had already been predicted from Newtonian principles by John Michell way back in 1783) led inevitably to the idea of gravitational time dilation. If you're on Earth, and you're receiving gravitationally-blueshifted signals from a satellite broadcasting from deep space, then you're receiving those signals faster than the nominal rate at which they're being created.
The only way that those signals can continue to be received at a higher rate than they are sent, for an arbitrarily-long period of time (explained Einstein), is if the satellite (in its weaker-gravity environment) is genuinely ageing more quickly than the observer down in the Earth's gravity-field.

So, the idea that light "falls" in a gravitational field (which is pretty much essential for the equivalence principle to work) leads inexorably to the idea that time must run at different rates in different gravitational environments. It was Einstein that spotted this, but his argument was a fairly general one.

When the Sun's gravity-well is modelled as distorting time coordinates as well as spatial ones, you get that extra precession of Mercury's orbit.

Incidentally, Einstein's gravitational time dilation paper (1911) is quite readable. He actually uses Newtonian calculations (rather than SR) to simplify the working, which is handy for me, because when someone tells me that gravitational time dilation wouldn't be expected to happen unless you assume SR/GR, I just have to point them to that paper, and point out Einstein's non-SR NM working, and point to the pre-GR date.

Once Einstein had pointed out that gravity warped time, the race was on to resurrect the old failed C19th curved-space project, and redo it as a curved-spacetime model. Einstein got his theory completed before the other guys (partly helped by World War One screwing up some of the schedules of his competitors).
In order to get to the finishing line first, Einstein is supposed to have driven himself close to a breakdown, and in order to speed things up a little, he seems to have adopted special relativity as as building block instead of going all the way back to first principles, starting with a blank page, and devising the theory as a fully curved-spacetime model from the bottom up.

That's why I think GR1915 has ended up flawed.
There's no obvious reason why a theory that assumes the equivalence of inertial and gravitational mass should reduce to a different theory that describes inertial mass in the absence of gravitational effects. If inertial mass and localised energy are always supposed to be associated with spacetime warpage, it's not obvious that the reduction of GR1915 to a theory that violates those two principles is legal.
The decision to do it that way was understandable at the time, but Einstein later rejected the two-stage "SR plus GR" approach and said that he no longer believed that it could be justified.

Unfortunately, he didn't have time to write yet another theory of relativity that would eliminate GR's problematic dependency on SR, and after he died, nobody else seemed to pick up where he'd left off. So we've been kinda stalled in this regard for the last fifty years.

[sol invictus]

Yep, that's why I wasn't sure why you were querying “90 degrees to what?” It should have been clear from the context.


Just so you know, one of the primary quantities measured at accelerators is the differential cross section - that's the number of scattering events as a function of the angle from the beam in which the particles fly off at that angle and hit the detector. Computing that is one of the main things you learn to do in relativistic quantum field theory - NM would give completely different answers when the particles are moving fast - and the results of those calculations are verified by experiment to incredible accuracy.

Any deviation at 90 degrees (if that's what you think should happen, I still have no idea) would be ruled out with very, very, very high confidence.

[ErkDemon]

That's impossible - the dispersion relations aren't the same.
Look: if we agree on the momentum (and the rest mass), the energy is determined. You cannot specify them independently, and the equation that determines them in SR isn't the same as the equation that determines them in NM. So we cannot agree on the energy and the momentum in SR and NM at the same time - that's a nonsensical requirement.

Okay, I think we've gotten off on the wrong foot.
Let me backtrack slightly and start again, and try to explain things a little better.

Firstly, I'm not arguing for the wholesale resumption of textbook Newtonian mechanics. That was never the plan, and the fact that this shiny new set of basic relationships just happened to correspond to what I'd consider to be the defining core (optical) relationships of NM was pretty annoying. As far as textbook NM is concerned, I consider that to be an unfinished project, with nasty omissions, and there are parts of it that (IMO) were never really made properly consistent.

This approach didn't arise from an attempt to update textbook NM. The original idea was to produce a better derivation of the SR relationships, that didn't rely on the slightly unrealistic assumption of flat spacetime. The plan was to derive a more general continuum of potential relativistic theories that included SR, selecting the positive-curvature range, and then collapsing that range of possibilities to a single solution, which I'd fully expected to then give the relationships of SR. But my little exercise went horribly wrong, and the further I got into this, the more I realised that it's not just that the special theory of relativity is incompatible with general curved-spacetime rules (that's old news), but the basic equations of motion for the theory seem to be geometrically incompatible with the physics of a universe in which moving bodies affect the way that light propagates (i.e., ours).
So my attempts to isolate a single preferred solution refused to give the “SR” answer I wanted. It kept throwing up a more redshifted “NM-like” solution instead, which used relationships that were fully one Lorentz-factor “click” away from those of SR.

Navigating the Range
You can move from any one of the potential theories in this range to any other, by multiplying in or dividing out a suitable Lorentzlike factor in a consistent way, and because of the wonderfulness of these Lorentzlike factors, this process preserves all sorts of nice results (like E=mc^2) across all members of the family. The location of each solution in the range turns out correspond to the degree of velocity-dependent curvature in the resulting model. If we dictate that there should be no gravitomagnetic effects at all, then there's only one solution that has that property, at the extreme limit of the selected range (SR). But if we allow that gravitomagnetic effects really do exist, we find ourselves having to look at “redder” solutions that do not use the exact relationships of special relativity.
Other than SR, the other main solution that obviously jumps out is the one that's “redder than SR” by exactly one Lorentz factor “click”, and that also turns out to be the one that has the same optical relationships as old Newtonian emission theory, and also turns out to be the only solution that allows classical indirect radiation through gravitational horizons. That's the one I got stuck with and couldn't get rid of.

So, to summarise:

Family of solutions, × requirement of zero velocity-dependent curvature = “SR” solution
SR solution × “Lorentzlike” redshift => various other, “gravitomagnetic” solutions
SR solution × Lorentz redshift = gravitomagnetic solution compatible with Hawking radiation


The NM ish solution
The member of this family that has been explored in most depth is, of course, the zero-curvature solution, special relativity.
As previously mentioned, the “NM-like” solution generates the same optical relationships for the change in the energy and momentum of light with velocity as Newtonian mechanics, and like all the other solutions, it generates E=mc^2. The requirement that the energy and momentum of an object changes in the same way at that of an equivalent complex of light then dictates that the corresponding momentum law has to be p=mv, which is again the relationship that we get from Newtonian mechanics. The law that we get for the energy of a moving object will have the earlier E=mc^2 result folded back into it, and therefore won't be the same as the textbook Newtonian relationship. It might arguably be what textbook NM should have eventually evolved into if we'd continued to develop it, but since it involves E=mc^2, which isn't normally considered a “Newtonian” result (!) this one won't be in the books.

I didn't make that clear, and for that I apologise to Sol. For energy and momentum, light and matter, three of the four combinations are going to agree with the textbook NM versions, the fourth would have to be an updated version. Since I usually only work with the “optical” stuff (which for my purposes are the more fundamental relationships, and would be what the fourth thing would have to be derived from), I forgot to mention that. Sorry.

“Rebuilding” vs “translating”
Since the HR-compatible solution shares its basic optical relationships with NM, we could work up its properties by starting with NM, and building a new, modernised “Newtonian” model from scratch around the idea that every particle represents a "dent" in spacetime, and that that dent tilts and deepens as its relative velocity w.r.t. surrounding matter increases. The gravitomagnetic effects regulate local lightspeeds, and solve the problems that old emission theory had with not being wave-compatible and with making inconsistent signal flight-time predictions. The difficulty with doing this this is that it involves reinventing the wheel, and if we get our information about what NM should predict from textbooks, a certain amount of that info won't be reliable, or won't work properly (like the aforementioned mass-energy relationship). F'rinstance, where special relativity would predict a Lorentz transverse redshift, our new model needs to predict a Lorentz-squared redshift. We can correctly calculate this result using NM optics (as an aberration redshift), but to do this correctly we have to ignore any SR literature that says that transverse redshifts weren't predicted by earlier theories ... people who take that literature too seriously are then liable to look at what we've done and declare that we did it wrong, because it disagrees with what they've been taught about what theories predicted before SR came along.

So while people who already know a few old models might prefer to leverage and extrapolate from what they already know about emission theory, for more mainstream physics people it's probably more sensible to start with the one member of the family that has been intensively studied and that they're already familiar with – special relativity – and carefully rescale its predictions and definitions by a Lorentz factor to get the “alternative” answer, without referring too much to what they think they already know about older relationships

Compatibility with Existing Physics
In quite a few situations, this rescaling, done properly, will make no difference at all to the final physical predictions ... in which case, if you're an SR-trained physicist working on one of these problems, you probably won't care which of the solutions is really right, and you might as well just continue using special relativity. If you start with one solution's derivation of E=mc^2 (either SR's or NM's), and rescale your relationships consistently, you still get E=mc^2 for any other solution in the range. If you calculate the straight-line, constant-velocity decay position of a particle using one solution, it should be precisely the same with all the others. All these solutions necessarily use the same relativistic aberration formula, they'll all predict gravitational shifts and gravitational time dilation, and with the help of the equivalence principle, they'll all predict that a circling particle in a storage ring should age physically slower by an amount that depends on the physical acceleration. Everything in the range between the SR and NM solutions will generate the same lightspeed upper limit to how fast you can directly accelerate a particle, and can be used to argue for the same “good” set of verified effects that are predicted by GR1915 .

If you run a particle accelerator and it works fine today using SR calculations, then it'll continue to work fine tomorrow. Where an acoustic model will start predicting effects that don't arise with SR ... particles appearing in places where SR says they shouldn't be thanks to indirect radiation ... where these are significant, you'll probably already be modelling those effects separately using quantum mechanics, and be describing them as separate quantum effects (e.g. quantum tunnelling).
The success of special relativity (and of special relativity supplemented by QM) reinforces the idea that, as long as the principle of relativity itself is correct, for an awful lot of physics experiments it doesn't seem to make a hell of a lot of difference which theory of relativity (in our range) is the right one.

But there'll be at least some cases where the difference should matter, so it'd be sensible to work out what those are, so we know which experiments are sensitive to the choice of solution, and which aren't.

To recap: if the motion of bodies does influence the propagation of nearby light (and experiment and logic suggest that it does), then, if relative velocity of physical bodies distorts the lightbeam geometry, and takes us away from a Minkowski metric, then it'd seem that the equations of motion must be different to those of SR. The question is how much by. Any deviation from SR would be interesting, because once we've broken the principle that SR's relationships are unique, we can allow the possibility of a quite sizeable deviation ... and the properties of the family of solutions described above, and the way that all these solutions seem to generate a lot of the results associated with SR, allow the possibility that the actual underlying equations might still be significantly different to those of SR, even though a lot of experimental outcomes seem to correspond exactly to the SR predictions.

It removes our ability to say: “This experiment agrees with SR, therefore SR must have the right equations, or at least the real relationships must be incredibly close to those of SR”.
If the selected experiment happens to be one of those that is relatively or completely insensitive to the choice of solution, this isn't necessarily true.

[ErkDemon]

This was all I was able to find on the web in a short search, there were some papers I could find as well.
Was "Observerspace' on wikipedia


I suppose I ought to mention the The Book:
Relativity in Curved Spacetime, Eric Baird (2007)
ISBN 0955706807 / 9780955706806
preview thumbnails (http://www.relativitybook.com/book_thumbs.html) / contents (http://www.relativitybook.com/book_contents.html) / reviews (http://www.relativitybook.com/book_reviews.html) / Chocolate Tree Books (http://www.chocolatetreebooks.com/)

It's a non-standard look at relativity in general, that builds to some of these “acoustic metric” arguments, and towards the end there's some stuff on QM-type principles applied to systems (especially social systems) and how they go wrong (belief systems, logical black holes, conspiracy theories, etc.).
library link (http://www.worldcat.org/oclc/181743934&tab=holdings?loc=Japan#tabs)

There's also a dedicated book on acoustic horizons used to model black hole radiation, but it's five times the price (!):
Artificial black holes, M Novello; Matt Visser; G E Volovik (2002)
ISBN 9810248075 / 978 9810248079
World Scientific's page for the book (http://www.worldscibooks.com/physics/4861.html)
library link (http://www.worldcat.org/oclc/51548418&referer=brief_results)

disclosures: okay, guilty, I also wrote the original versions of the “observerspace” and “acoustic metrics” wiki pages previously mentioned.

[Terry]

Isn't "the sceptic's view of special and general relativity" something along the lines of phenomenally well supported by a metric ****-ton of evidence, and some of the most successfull physics ever ?

[sol invictus]

I'm sorry, but I still have absolutely no idea what you are talking about. I don't know why you think there's a problem, I don't know how you want to modify the theory, and it seems from the exchange above that you didn't know that the energy-momentum dispersion relation is different in SR than it is in NM. That fits you squarely into the category of the run-of-the-mill physics crank - no understanding of the basics of the standard theory, but certain that something must be wrong with it.

If this theory you're referring to has a different dispersion relation than SR - which is what you originally claimed - it was long ago ruled out by data. If it does not, it is SR.

Professional physicists spend a fair amount of time looking for violations of SR (some even expect they should be there) and we know very well what the limits are (meaning how large of a deviation can exist and be consistent with data). Depending on the form of the correction to SR, the correction must be smaller than one part in 10^15 or smaller.

Changing the power of gamma in any of the energy/momentum/velocity relations by anything other than some incredible small amount is in total conflict with a ridiculous number of experimental results.

[Dancing David]

Um, I am having a very hard time fining any information about this Eric Baird.

[sol invictus]

Um, I am having a very hard time fining any information about this Eric Baird.

Well, 4 preprints come up from a SPIRES search, all from 1998-99, not a single one of which has any (non-self) citations:

http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=ea+Baird,+Eric

Only one is published, and that one in a journal called "Galilean Electrodyn.", which sounds extremely suspicious.

9 more come up from an ADS search:

http://adsabs.harvard.edu/cgi-bin/nph-abs_connect?db_key=AST&db_key=PRE&qform=AST&arxiv_sel=astro-ph&arxiv_sel=cond-mat&arxiv_sel=cs&arxiv_sel=gr-qc&arxiv_sel=hep-ex&arxiv_sel=hep-lat&arxiv_sel=hep-ph&arxiv_sel=hep-th&arxiv_sel=math&arxiv_sel=math-ph&arxiv_sel=nlin&arxiv_sel=nucl-ex&arxiv_sel=nucl-th&arxiv_sel=physics&arxiv_sel=quant-ph&arxiv_sel=q-bio&sim_query=YES&ned_query=YES&aut_logic=OR&obj_logic=OR&author=baird%2C+eric&object=&start_mon=&start_year=&end_mon=&end_year=&ttl_logic=OR&title=&txt_logic=OR&text=&nr_to_return=200&start_nr=1&jou_pick=ALL&ref_stems=&data_and=ALL&group_and=ALL&start_entry_day=&start_entry_mon=&start_entry_year=&end_entry_day=&end_entry_mon=&end_entry_year=&min_score=&sort=SCORE&data_type=SHORT&aut_syn=YES&ttl_syn=YES&txt_syn=YES&aut_wt=1.0&obj_wt=1.0&ttl_wt=0.3&txt_wt=3.0&aut_wgt=YES&obj_wgt=YES&ttl_wgt=YES&txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

The guy is a crank. Presumably he's you, ErkDemon?

[MattusMaximus]

That sounds cool! If you don't mind me asking, how is that done?


It's really a pretty simple experiment in principle. You have basically a stack of plastic disks to serve as your detector; the muons passing through this detector will occasionally get stuck inside. When that happens, due to their deceleration, they'll emit a photon of light - later, after they decay, these same muons will emit another photon.

You have the detector hooked up to a photomultiplier tube or similar device which detects the photons, and you attach the entire contraption to an oscilloscope.

On the scope, you can get a measurement of how long it takes the muons to decay by looking for the photon events over a LOT of detections (~500 or so). What you end up seeing at the end of the analysis is that these muons survived longer than they would normally in a state of rest. The explanation of why they survive roughly 10 times longer than normal (at rest) is due to time dilation; it is estimated that they're moving at about 0.9952c.

Here's a photo of the setup on a table top...

http://forums.randi.org/imagehosting/thum_774747a54be4dc431.jpg (http://forums.randi.org/vbimghost.php?do=displayimg&imgid=10555)

Plus here's a link that gives more information about how the experiment is set up and conducted...

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/muon.html#c1

[MattusMaximus]

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

Look at the precession of the perihelion of mercury. It's very accurately measured and completely consistent with general relativity. The claim made in the article above, is that this modified factor cancels the Lorentz factor and returns us to newtonian dynamics....which means this phenomenon that couldn't be explained until general relativity and under this new theory goes back to being unexplained again.


Not to mention that we now have a whole host of technology based upon the theory of general relativity. For example, anything which deals with a satellite hookup and high-speed electronics must take into account the GR phenomena of gravitational time dilation (since time will pass at a different rate on the satellite vs. here on the planet), otherwise the calculations would be off.

And if that were the case, then goodies like satellite phones and GPS receivers wouldn't work. The fact that they do is proof of the validity of GR.

[sol invictus]

And if that were the case, then goodies like satellite phones and GPS receivers wouldn't work. The fact that they do is proof of the validity of GR.

That's absolutely correct, but this guy is disputing SR too - and SR is far better tested than GR.

[MattusMaximus]

That's absolutely correct, but this guy is disputing SR too - and SR is far better tested than GR.


Wow, talk about biting off more than you can chew :rolleyes:

[ErkDemon]

Isn't "the sceptic's view of special and general relativity" something along the lines of phenomenally well supported by a metric ****-ton of evidence, and some of the most successfull physics ever ?

No, that's the enthusiast's view of special and general relativity. :)

Any fool can argue that a currently-dominant theory is correct, and can back that up with quotes and lists of opinions and interpretations that support the status quo. That doesn't really require any particular intelligence.

However, on a skeptics forum I kinda hope to find a few people whose minds are sharp enough to be able to bypass the sheep-like "Everybody important seems to say this thing so it must be true" mindset, while avoiding the trap of "Everybody important seems to say this thing so it must be false".

[Megalodon]

No, that's the enthusiast's view of special and general relativity. :)

Any fool can argue that a currently-dominant theory is correct, and can back that up with quotes and lists of opinions and interpretations that support the status quo. That doesn't really require any particular intelligence.

However, on a skeptics forum I kinda hope to find a few people whose minds are sharp enough to be able to bypass the sheep-like "Everybody important seems to say this thing so it must be true" mindset, while avoiding the trap of "Everybody important seems to say this thing so it must be false".

I'm easy to convince...

Please point three observations that are not consistent with SR and GR and are explainable by your theory.

Then show how your theory equally explains observations that are consistent with SR an GR.

Thanks

[ErkDemon]

Not to mention that we now have a whole host of technology based upon the theory of general relativity. For example, anything which deals with a satellite hookup and high-speed electronics must take into account the GR phenomena of gravitational time dilation (since time will pass at a different rate on the satellite vs. here on the planet), ...

See post #19: "gravitational time dilation is a fairly general effect"

Einstein's argument for gravitational time dilation was produced a few years before his general theory, and doesn't depend on special relativity. It's a general, very basic argument that seems to be inevitable one you accept the idea of gravitational shifts.

The idea of gravitational shifts also doesn't depend on Einstein's special or general theories, and the things were actually predicted back in 1783 by John Michell. His prediction and working (and a few other juicy ideas about objects bounded by gravitational horizons) were published by the Royal Society in their 1784 volume. Einstein's own 1911 paper used Newtonian arguments for convenience.

Some of the stuff that's supposed to be unique to SR and GR is actually much more general than some people would have you believe.

And if that were the case, then goodies like satellite phones and GPS receivers wouldn't work. The fact that they do is proof of the validity of GR.

No Mattus, if you believe that, then I'm afraid you've been suckered.

If you'd rather take the word of someone more "authoritative" than me, try Cliff Will:
"Was Einstein Right?" Clifford M. Will (1986) (http://www.worldcat.org/search?q=0192822039)
Chapter 3, "the gravitational red shift of light and clocks":
" Another thing that should be apparent is that we again did
not use general relativity anywhere in the discussion. The
gravitational red shift depends only on the principle of equiva-
lence. Even though Einstein viewed the red shift as one of his
three main tests of general relativity, we now regard it as a more
basic test of the existence of curved spacetime. Any theory of
gravity that is compatible with the equivalence principle (and
there are many, including, for instance, the Brans-Dicke theory)
automatically predicts the same gravitational red shift as gen-
eral relativity. "

This has been known and appreciated for quite a long time, now.
So if anybody purporting to be an expert has recently tried to tell you that "GPS receivers wouldn't work properly unless Einstein's general theory was right", then I'm afraid that perhaps they weren't being entirely honest with you about their level of expertise, or (if they really do know their stuff) they weren't being entirely honest with you about the science.

[Ziggurat]

Some of the stuff that's supposed to be unique to SR and GR is actually much more general than some people would have you believe.

Does the precession of Mercury's orbit fall into that category? I haven't heard that it does. And how about frame dragging? That wasn't measured in 1986, but it has been now.

As has already been asked, are there any alternative theories which not only explain everything GR does but also explain something GR doesn't?

[ErkDemon]

Um, I am having a very hard time finding any information about this Eric Baird.

In the 1990s I ran what was probably the net's most popular relativity-based website, "Erk's Relativity Pages" ("posh" sites like Britannica used to link to its library sections). Got rather a lot of traffic, incredible search engine rankings, upset a few people, had a few academics trying to get it shut down (a couple of them were nice enough to email me to let me know what they were doing). Took the site offline about ten years ago.
I also converted Einstein's "Relativity" book to Windows helpfile format and put it on the net (you might still be able to find unofficial archived copies of it on other sites by googling for a file called "relativ.hlp (http://www.google.co.uk/search?q=%22relativ.hlp)" ).

During that time I was trying to find a way to disprove an alternative class of relativistic model that I'd stumbled across while trying to produce a more ambitious, gravitomagnetically-compatible rederivation of SR's relationships. What I found was that the approach seemed to be incompatible with SR, but that there was a whole class of alternative "gravitomagnetic" solutions that weren't listed in the textbooks, and which were usually ruled out by saying that "we know that spacetime is flat" for simple mechanics. Which, of course, we don't.
During that time, one of my major frustrations was that I kept finding that the "facts" that professorial types gave me kept turning out to be not quite right, so I had to develop a "clean room" approach, and go back to all the original papers, and come up with new methods from scratch. I think I probably skimmed through or read every relevant paper published in an English-language journal in the British Library's collection between WW2 to y2K, and went through the major London book collections as far back as the C18th.
The website kinda doubled as a research diary, and the discipline that I worked to was that nothing went onto the site, however trivial, until it had been worked through from scratch, and/or checked against primary sources (or as close as I could get to primary sources).

Since the "gravitomagnetic" model was unexpectedly difficult to disprove, I figured that I ought to pull the plug on the website and try to write a proper paper on it, but since the idea conflicted with so many taught "facts" that weren't actually right, I first had to produce a slew of smaller papers tackling individual topics that didn't yet seem to have been properly documented by anyone else, but which you had to know about for the larger picture to make any sort of sense (the generality of E=mc^2 and "transverse" redshifts in pre-SR theory, the "pair-production" description of Hawking radiation as an artefact of applying GR-style metrics to non-GR physics, that sort of thing).

At this point, the sort of guys who'd earlier been clamoring for me to be somehow banned from the net or delisted by the search engines started campaigning for me to be banned from the Los Alamos e-print archives (!), but there wasn't a lot they could do about it. My big paper tying together the earlier work had some problems, some of which I managed to identify and tackle in a smaller followup. With hindsight, it still wasn't really entirely satisfactory.

One of the points I realised was that by founding a relativistic model on different classical principles to SR, I'd accidentally ended up predicting indirect radiation through a gravitational event horizon. I was initially told that his meant the model was wrong (because "black holes don't radiate, on principle"), but after I realised that what I'd produced was a classical description of Hawking radiation (in a non-GR1915 context), this turned from a "bug" to a "feature". I initially had trouble getting anyone to accept the concept of "classical" Hawking radiation ("HR is a quantum effect, yours isn't") until Matt Visser produced a paper (http://arxiv.org/abs/gr-qc/9712010) towards the end of the 1990's looking at the overlooked subject of this sort of "gravitomagnetic" metric (="acoustic metrics"), and declared that the associated indirect-radiation effect was legitimately referred to as Hawking radiation (he'd already been considering these issues for a while (http://arxiv.org/abs/gr-qc/9311028)). The subject of acoustic metrics then took off in earnest as a way of modelling HR, so I now didn't have to worry about validating that section of the theory, the quantum gravity guys were now tackling all that quite happily without me. The part that they didn't seem to want to touch with a bargepole was the non-SR aspect. They were going to great lengths to make it clear that they weren't proposing a literal alternative classical model, and that their work was merely a "toy model" for QG, or an "analogue" for how a future theory of QG would work. The classical field theory guys didn't feel threatened by QG , because they were told that it would eventually be a superset of SR/GR. Heh.
So while the classical field theory guys couldn't really study these problems without risking being considered crackpots (because reduction to SR was considered mandatory for gravitational models), the QG guys had their own little safe haven where they could study what they liked.

Towards 2003/2004, I figured that perhaps my continuing presence might be deterring mainstreamers from following this work up, so I stepped out of the ring, and waited for someone to "discover" the non-SR implications of these acoustic metrics and publish in time for the 2005 Einstein anniversary. They'd get the credit rather than me, but at least the thing would get done, and hopefully some of my groundwork (and the "trail of breadcrumbs" I'd left over the Compuserve and USENET forums) would help them along if they got stuck.
Hawking's work was now reaching a bit of a crisis over the black hole information paradox ... he'd been presuming that GR had to be right and that QM would need to be rewritten, but he was running out of options, so my schedule had Hawking retracting in March-April 2005, and Preskill realising the non-GR implications and publishing something in May-June 2005, giving us a nice PR story for how we were facing a revolution in basic physics on the 100th anniversary of SR.
It didn't quite happen like that. Hawking's announcement of a change of mind came out later that I'd expected, and that spoilt the dynamic. It got to the end of 2005, and nobody had stepped up and joined the dots together.

By 2005 I'd already put my library out for recycling, shredded my notes and reformatted all my hard-drives in an attempt to go completely "cold turkey" from theoretical physics and get myself some sort of a life. But then I found myself working for a book production company, and decided that this new technology was pretty cool, and I ought to produce a book on something, and after a few weeks mulling over the idea of a tourist guide, it struck me that I could recycle all the old work as a book (luckily about 2/3 of my original library's index was still on my PDA as a spreadsheet file that I'd forgotten to delete).

So I quit my job in late 2006, spent the next year writing and assembling the graphics for the book, "Relativity in Curved Spacetime (http://www.google.co.uk/search?q=0955706807)" and put it out in late 2007 as a paperback. The book replaces all the older documents (including the two "problematic" later papers) and is just under 400 pages including the reference section. The hardback version (for the benefit of libraries) is scheduled for mid-July.

... And here we are.

[ErkDemon]

The guy is a crank. Presumably he's you, ErkDemon?

Most (not all) of those hits refer to me. But there seem to be quite a few people about with the same name, some doing math and/or physics, so I try to use a more distinctive signoff.
My real name's listed on my JREF profile page (I notice that yours isn't), which anyone can look at by clicking the JREF handle alongside anything I post, so it's not exactly a secret. Also, the profile uses a distinctive part of the book cover-graphic, and also links explicitly to the book's webpage, so, again, I'm not exactly sneaking about (sorry to disappoint the conspiracy theorists).
Also, I briefly introduced (http://forums.randi.org/showpost.php?p=3416717&postcount=7247) myself when I got here.

Simply calling someone a crank isn't exactly a scientific argument. One of the ironies of theoretical physics is that although physics is supposed to be about cold, hard, objective logic, reason and evidence, some of its practitioners seem to spend an awful lot of time indulging in childish name-calling and projecting what hey see as "obvious" emotional or mental disorders onto anyone who disagrees with them.
Sociologically and psychologically, it's an ... interesting ... community.

[Dancing David]

um, ED it might have been just easier to say "I am he", I think that is what you said?

[sol invictus]

Hawking's work was now reaching a bit of a crisis over the black hole information paradox ... he'd been presuming that GR had to be right and that QM would need to be rewritten, but he was running out of options, so my schedule had Hawking retracting in March-April 2005, and Preskill realising the non-GR implications and publishing something in May-June 2005, giving us a nice PR story for how we were facing a revolution in basic physics on the 100th anniversary of SR.
It didn't quite happen like that. Hawking's announcement of a change of mind came out later that I'd expected, and that spoilt the dynamic. It got to the end of 2005, and nobody had stepped up and joined the dots together.

Please. Hawking's proposed resolution to the info paradox - which is wrong at least in its details, by the way, and is not original to him - has absolutely nothing to do with the stuff you've been rambling about here. It's far more radical.

For someone with so much experience with relativity, someone who thinks he can overturn century old science supported by a humongous amount of experimental data, it's rather odd that you didn't know even the basic relationship between energy and momentum in special relativity that every physics student learns in high school or as a freshman, isn't it? How should we interpret that?

[sol invictus]

I notice you never answer any of the specific questions about your "work" people ask you. While you are more articulate than most, you fit perfectly into the physics crank mold.

There are many, many others like you out there (including quite a few posting on this forum) - do you realize that?

[sol invictus]

This (http://arxiv.org/abs/0804.0016) paper summarizes the situation nicely.

[ErkDemon]

Just so you know, one of the primary quantities measured at accelerators is the differential cross section - that's the number of scattering events as a function of the angle from the beam in which the particles fly off at that angle and hit the detector. Computing that is one of the main things you learn to do in relativistic quantum field theory ...
- and the results of those calculations are verified by experiment to incredible accuracy.


IMO, using the success of relativistic field theory to argue for SR isn't a good idea, because quantum field theory can be used to replicate exactly the sorts of effects that I'd argue that special relativity seems to be missing.
QFT seems to be capable of acting as a sort of "universal bandaid" for bad classical models, with anything that the classical model gets wrong being fixed up by the QM layer.

For example, compare these three descriptions, for (i) the type of “gravitomagnetic” model suggested, (ii) SR, and (iii) QM:


If the motion of bodies affects nearby light, then a particle moving through its environment should appear to be immersed in a sort of polarised gravitational field ... the particle should be associated with a curvature “footprint” that doesn't just describe its rest mass but also its energy and momentum, and as it whizzes past discontinuous features in its background, those features will be hit by the moving field. The particle and these features can interact via their combined gravitomagnetic field without undergoing a conventional collision. These indirect partial-collisions-by-proxy allow indirect information transfer and momentum exchange, and mean that the mass-properties of the particle don't exist solely within the particle but are smudged out into the surrounding region of space.
With special relativity's description, this can't happen. It's an article of faith under SR that moving bodies have no interaction with the propagation of nearby light, so this extension of a moving particle's momentum into the surrounding region as a lightspeed offset won't occur, and we won't get that “gravitomagnetic” description of indirect coupling effects between masses.
However, once we involve QM, we find that the energy and momentum of a particle can't be precisely localised, and have to be smudged out over the surrounding region. The moving particle is therefore surrounded by a probability-field that describes its energy and momentum, and this field can interact with discontinuous passing features to allow indirect information exchange and momentum-transfer ...


The descriptions of (i) and (iii) coincide, and the SR description (ii) is the odd man out. I'm suggesting that (i) may be the correct classical interpretation, and that (iii) may be how the statistical mechanics of (i) then translates into the language of quantum mechanics.

So, if (i) was fundamentally correct, and (ii) was fundamentally wrong, a highly-trained physicist who believed that special relativity couldn't be wrong could combine SR with QM, use quantum field theory to reproduce the effects of (i) in a model that nominally reduced to (ii), and claim that the success of the final composite model therefore represented a striking predictive success for special relativity, even though SR itself would in this case be failing to agree either with QM or with the physical data.

[sol invictus]

IMO, using the success of relativistic field theory to argue for SR isn't a good idea, because quantum field theory can be used to replicate exactly the sorts of effects that I'd argue that special relativity seems to be missing.

False. For example, non-relativistic quantum field theory would give totally wrong answers for the cross section, as would anything but a theory with almost precise Lorentz invariance. That can (and has) been proven - as I said, many people are looking for violations of Lorentz invariance, and they have calculated this very carefully.

QFT seems to be capable of acting as a sort of "universal bandaid" for bad classical models, with anything that the classical model gets wrong being fixed up by the QM layer.

Totally wrong. See above.

The particle and these features can interact via their combined gravitomagnetic field without undergoing a conventional collision. These indirect partial-collisions-by-proxy allow indirect information transfer and momentum exchange, and mean that the mass-properties of the particle don't exist solely within the particle but are smudged out into the surrounding region of space.

That is true (well, depending on what you mean by "gravitomagnetic", but I'll be generous), but it does not conflict with anything.

With special relativity's description, this can't happen.

False.

It's an article of faith under SR that moving bodies have no interaction with the propagation of nearby light,

Completely false. Where in the world did you pull that one from?

so this extension of a moving particle's momentum into the surrounding region as a lightspeed offset won't occur, and we won't get that “gravitomagnetic” description of indirect coupling effects between masses.

Well, if you're not including gravity there are no gravitational interactions. What a shock! However there can still be interactions at a distance from (for example) electromagnetic effects, and SR handles those correctly. If you are including gravity, we need to talk about GR, not SR.

However, once we involve QM, we find that the energy and momentum of a particle can't be precisely localised, and have to be smudged out over the surrounding region.

So? The same is true in classical field theory.

The moving particle is therefore surrounded by a probability-field that describes its energy and momentum, and this field can interact with discontinuous passing features to allow indirect information exchange and momentum-transfer ...

False, more or less. Relativistic quantum field theories have exactly the same causal structure that relativistic classical field theories do - there are no interactions outside the lightcone, period. That does not conflict with the uncertainty principle.

[MattusMaximus]

No Mattus, if you believe that, then I'm afraid you've been suckered.



Oh wow, you're right. I suppose my GPS actually doesn't work, despite the fact that it gets me where I want to go. Seems to me those GR based calculations of gravitational time dilation are working pretty well.

Suckered, indeed :rolleyes:


If you'd rather take the word of someone more "authoritative" than me, try Cliff Will:
"Was Einstein Right?" Clifford M. Will (1986) (http://www.worldcat.org/search?q=0192822039)
Chapter 3, "the gravitational red shift of light and clocks":


No thanks, and no points either. Arguments from authority are a very poor way to present your claims here, ED. I could cite Einstein himself as an authority on physics, but if we were talking about quantum theory he'd be a very poor selection since he never even accepted QM. See? Even the mighty Einstein can be wrong.

But on SR and GR, it seems that he did get it right. And as Sol has already pointed out, we have loads of evidence supporting both SR and GR. GPS receivers is just one thing.


This has been known and appreciated for quite a long time, now.
So if anybody purporting to be an expert has recently tried to tell you that "GPS receivers wouldn't work properly unless Einstein's general theory was right", then I'm afraid that perhaps they weren't being entirely honest with you about their level of expertise, or (if they really do know their stuff) they weren't being entirely honest with you about the science.


And why exactly would the scientific community want to lie about something like this? I can't wait for the answer to this question... anybody want to guess what the response will be?

[ErkDemon]

I'm easy to convince...
Please point three observations that are not consistent with SR and GR and are explainable by your theory.

If you want three obvious physical observations that unambiguously require a new theory (and can't be fudged somehow under current theory), I can't help you. We're just too good at inventing new rules and laws to explain away inconsistencies! ;) But I also can't give you three physical observations that were known and accepted in 1905 whose explanation would have required special relativity, or three physical observations in 1915 that would have required general relativity for their explanation. So if my suggested relativistic model fails this test, Einstein's would have failed it, too.

If this model's right, it'll explain why some experimenters have been finding too much redshift in their SR tests, but they're currently able to explain this away as the result of miscellaneous hardware problems. It would have predicted the thermal redshift effect that Pound, Snider & co stumbled upon by accident in the 1960's (the “SOD” effect), but it's too late to claim that as a “prediction” now. It “predicts” the Fizeau result, explained as the result of short-range non-SR dragging effects, but we've already found a way to explain that result with an additional layer of non-SR theory.
It successfully predicts Hawking radiation effects (which don't appear under SR/GR1915), but these still tend to be regarded as QM-specific effects rather than something that a classical theory should predict (this attitude may be slowly changing).

It does eliminate some arbitrary-looking distinctions and categorisations that appear in current theory for no apparent reason (other than necessity). Eliminating arbitrariness and streamlining the number of independent assumptions and rules is generally considered A Good Thing, but an arbitrary distinction often isn't considered arbitrary at the time.

Some of the things it eliminates:

The SR layer underpinning GR. Since GR introduces a more sophisticated concept of c-constancy and more sophisticated lightspeed-regulation mechanisms, why not use them everywhere? Why keep SR's version of lightspeed constancy in flat spacetime, when GR principles arguably make the idea of “flat spacetime physics” irrelevant? Why not apply the GR approach more consistently, right down to the particle level? This gives us a gravitomagnetic description of conventional mechanics, and replaces SR's Minkowski metric with an acoustic one. If we can get away with it, it's a major simplification in some ways. One set of rules operating everywhere.
Different laws at different scales. We're taught that GR is the theory of the very large, whereas QM is the theory of the very small. Allowing GR an acoustic metric seems to remove that distinction.
Cosmological vs gravitational horizons. Under GR1915, these have to be treated differently ,under this model a topological twist seems to be able to turn one description into the other.
Different redshift laws. Under GR1915, a distant galaxy might have an effective Hubble recession speed plus a conventional recession velocity component. Under GR1915, these two shift laws are different, under this system a Hubble redshift can be expressed as a velocity redshift or as a pseudogravitaitonal redshift, the calculations become interchangeable.
Black hole information paradox. If you give GR this sort of acoustic metric, it's able to radiate through a gravitational horizon, and we get Hawking radiation effects, from classical principles. Having the BHIP solved would make some researchers very happy (and let them get on with other things).


Then show how your theory equally explains observations that are consistent with SR an GR. Thanks

In brief, the bits of GR that are observationally good (being based on the Equivalence Principle, curved spacetime, the most general principle of relativity) carry over. As far as GR testing is concerned, if it supports GR, it almost certainly supports this, too. The parts of GR that are more "problematic" almost all seem to be the fault of that separate "EP-incompatible " SR layer, and that's the part of GR that I'm deleting.

As far as SR testing is concerned, all the results that depend on the PoR, but don't depend on flat spacetime carry over (e.g. searchlight effect, no preferred frame).
As far as SR results that are generally presented as being unique to SR, some carry over perfectly (E=mc^2, straight particle tracklengths) others are qualitatively the same, but quantative assessments can sometimes be more slippery then expected because of the number of different redefinitions when we switch between models. You still get transverse redshifts (but as an aberration effect), a lightspeed limit to direct acceleration in particle accelerators (as a "coupling efficiency" issue), the same physical time dilation in particle storage rings (as a gravitational time dilation effect due to the centrifugal field), the same Halfele-Keating prediction (ditto).

There are some testable differences which really should have already been tested for, but since relativity textbooks tell us that non-SR solutions don't have to be considered, the guys who write test theories typically haven't included anything to take this sort of possibility into account, so reassessing the existing experimental record is difficult. It's still conceivable that something like this might have slipped under the radar without being spotted.
Different solutions have their own separate velocity-addition formulae, but the usual textbook SR v.a.f. verification experiments are too crude to tell them apart.
One result that does stand out is the old Ives-Stilwell test. If this model is correct, the I-S result has to be wrong, or has to have a lower accuracy than claimed. But then again, it's since been noted that I-S probably did have a lower accuracy than claimed, so ... dunno.

To get this issue resolved, I think we're probably going to have to go back and do a few of these tests again, with the experimenters asked to check for a wider range of possibilities.

[MattusMaximus]

ED, you haven't answered my question. Exactly why is it that you think the scientific community is lying about SR and GR?

[ben m]

See post #19: "gravitational time dilation is a fairly general effect"

If you'd rather take the word of someone more "authoritative" than me, try Cliff Will:

It's great that you take Clifford Will to be an authority on GR. Prof. Will is one of the world's experts on comparing GR (and GR's competitors) to experimental data. Will could tell you *exactly* what parts of GR are supported by GPS time dilation, and *exactly* what non-GR theories are ruled out by it. It absolutely *is* the case that gravitational time-dilation is consistent with some gravity models (including GR) and inconsistent with others.

Does it rule out yours? That's the question you seem to be dodging. How carefully have you compared *your* theory to Will's work (see, eg., http://relativity.livingreviews.org/Articles/lrr-2006-3/ (http://relativity.livingreviews.org/Articles/lrr-2006-3/), especially table 4)? What are *your* predictions for the eight constants in the PPN formalism (http://en.wikipedia.org/wiki/Parameterized_post-Newtonian_formalism)?

[ben m]

If you want three obvious physical observations that unambiguously require a new theory (and can't be fudged somehow under current theory), I can't help you. We're just too good at inventing new rules and laws to explain away inconsistencies! ;)

Which new laws are you thinking of? The "Great 2002 Fudge Factor" where Newton's Constant was quietly changed from 6.673(10) x 10^-11 to 6.6742(10) x 10^-11 ?

the same physical time dilation in particle storage rings (as a gravitational time dilation effect due to the centrifugal field)

Elaborate, please. Time dilation only happens due to centrifugal force? You, sir, are confused. Time dilation is observed in plenty of systems moving in straight lines, and also in plenty of systems with variable centrifugal forces, like the ESR storage ring at GSI.

One result that does stand out is the old Ives-Stilwell test. If this model is correct, the I-S result has to be wrong, or has to have a lower accuracy than claimed. But then again, it's since been noted that I-S probably did have a lower accuracy than claimed, so ... dunno.


Oh, so Ives-Stilwell's measurement of time dilation, which agrees with SR at 1%, is inconsistent with your theory? Then the recent repeat of this experiment, which agrees with SR at 0.00001%, can safely be said to have disproven your theory (http://www.mpi-hd.mpg.de/ion-storage/Lorentz/relativity.html). (And you don't have some sort of "centrifugal" escape hatch; the experiment was done in a straight-line section of the storage ring, not in the middle of a steering magnet.)

That's it.

[Megalodon]

If you want three obvious physical observations that unambiguously require a new theory (and can't be fudged somehow under current theory), I can't help you.

That's all right, I didn't think you could... thanks for playing, though...

We're just too good at inventing new rules and laws to explain away inconsistencies! ;)

Conspiracy theories is the second door to the left, down the hall.

But I also can't give you three physical observations that were known and accepted in 1905 whose explanation would have required special relativity, or three physical observations in 1915 that would have required general relativity for their explanation.

That's ok... I didn't think you could...

So if my suggested relativistic model fails this test, Einstein's would have failed it, too.

It would? That's nice... So what made Einstein's theories the current accepted model? Did he get a coupon on a cereal packet?

If this model's right, it'll explain why some experimenters have been finding too much redshift in their SR tests, but they're currently able to explain this away as the result of miscellaneous hardware problems.

It will? Time to write that paper for Nature, then... get busy...

It would have predicted the thermal redshift effect that Pound, Snider & co stumbled upon by accident in the 1960's (the “SOD” effect), but it's too late to claim that as a “prediction” now. It “predicts” the Fizeau result, explained as the result of short-range non-SR dragging effects, but we've already found a way to explain that result with an additional layer of non-SR theory.

Another paper for you, then. You shouldn't be wasting time in internet forums.

It successfully predicts Hawking radiation effects (which don't appear under SR/GR1915), but these still tend to be regarded as QM-specific effects rather than something that a classical theory should predict (this attitude may be slowly changing).

Brilliant! Where are the articles, then?

It does eliminate some arbitrary-looking distinctions and categorisations that appear in current theory for no apparent reason (other than necessity). Eliminating arbitrariness and streamlining the number of independent assumptions and rules is generally considered A Good Thing, but an arbitrary distinction often isn't considered arbitrary at the time.

I swear, if you tell me that it makes a decent cup of capuccino, I'll take two!

Some of the things it eliminates:

That's all nice and dandy, but... does it get rid of those hard to clean spots?

In brief, the bits of GR that are observationally good (being based on the Equivalence Principle, curved spacetime, the most general principle of relativity) carry over. As far as GR testing is concerned, if it supports GR, it almost certainly supports this, too. The parts of GR that are more "problematic" almost all seem to be the fault of that separate "EP-incompatible " SR layer, and that's the part of GR that I'm deleting.

So you claim to have done to Einstein what he did to Newton... but instead of publishing it in Science you are debating it in Internet forums? Shouldn't you be getting ready for that Nobel?

As far as SR testing is concerned, all the results that depend on the PoR, but don't depend on flat spacetime carry over (e.g. searchlight effect, no preferred frame).
As far as SR results that are generally presented as being unique to SR, some carry over perfectly (E=mc^2, straight particle tracklengths) others are qualitatively the same, but quantative assessments can sometimes be more slippery then expected because of the number of different redefinitions when we switch between models. You still get transverse redshifts (but as an aberration effect), a lightspeed limit to direct acceleration in particle accelerators (as a "coupling efficiency" issue), the same physical time dilation in particle storage rings (as a gravitational time dilation effect due to the centrifugal field), the same Halfele-Keating prediction (ditto).

Wait, I start to see some cracks....


[/QUOTE]There are some testable differences which really should have already been tested for, but since relativity textbooks tell us that non-SR solutions don't have to be considered, the guys who write test theories typically haven't included anything to take this sort of possibility into account, so reassessing the existing experimental record is difficult. [/QUOTE]

And it crumbles... Of course, it's those meanie scientists... if only they have listened to you...

One result that does stand out is the old Ives-Stilwell test. If this model is correct, the I-S result has to be wrong, or has to have a lower accuracy than claimed. But then again, it's since been noted that I-S probably did have a lower accuracy than claimed, so ... dunno.

Then, as ben m was so kind as to note, it's time for you to get back to the drawing board

To get this issue resolved, I think we're probably going to have to go back and do a few of these tests again, with the experimenters asked to check for a wider range of possibilities.

Now, bare with me... In my field, if I proposed a hypothesis that was proven wrong by an experiment performed 5 years ago, I would be heading to a whole new career in the food manufacturing industry... Why should anyone be kinder to your lack of research?

[MattusMaximus]

Bump.


ED, you haven't answered my question. Exactly why is it that you think the scientific community is lying about SR and GR?


ED, I'm still waiting for your answer...

[Dancing David]

Hmm, same as the PC/PU, when asked

"And what pysical evidence supports your theory?" there is a resounding silence.

[MattusMaximus]

Hmm, same as the PC/PU, when asked

"And what pysical evidence supports your theory?" there is a resounding silence.


Fuuny how that happens, isn't it? :rolleyes:

[ErkDemon]

Does the precession of Mercury's orbit fall into that category? I haven't heard that it does.

Yep, Mercury's "extra" precession is supposed to be a consequence of spacetime curvature. Some people had already been playing about with the idea of spatial curvature in the C19th, but the big change that happened in the C20th was the realisation that gravity also affected clockrates - so gravity curved "temporal" coordinates as well as "spatial" ones.

And how about frame dragging? That wasn't measured in 1986, but it has been now.

Yep. In this model, the frame-dragging idea's taken further (and I'd argue, applied more thoroughly) than it is under SR/GR1915.

Simple accelerational frame-dragging can be argued for, generally, from the Principle of Equivalence and/or from Mach's Principle. If a forcibly-accelerated object feels gee-forces, and feels the apparent acceleration of the outside universe pulling on it, then for background observers watching the accelerated body, they should in turn experience an apparent gravitational effect, too, due to the body exerting a similar effect on them. It should be a mutual thing.

Rotational frame-dragging: ditto. If the relative rotation of a hollow shell of matter around a body causes outward “centrifugal” and sideways “Coriolis” fields in the rotation plane (Mach's principle), then these effects should again be mutual. In a spatially-closed universe, we can take this description and flip it inside out, and treat the outside universe as a solid ball whose surface faces outwards, and the outer surface of our body as an enclosing sphere whose surface faces inwards. The rotation of the universe-ball should therefore increase its overall equatorial attraction, and should also tend to pulls nearby objects around with it (Lense-Thirring effect (http://en.wikipedia.org/wiki/Frame-dragging)).
So to someone alongside the equator of a rotating body, the receding section of equator should pull more strongly than the approaching part, but overall, the effect should be an increased equatorial attraction.

These arguments work for both GR1915 and the suggested alternative. Wheeler (http://en.wikipedia.org/wiki/John_Archibald_Wheeler)'s already pointed out that to get the standard predictions for the Gravity-Probe B experiment (http://en.wikipedia.org/wiki/Gravity_Probe_B), to the available experimental accuracy, we don't actually need general relativity, we only need to apply what he refers to as the “democratic principle”. If the rotational pull of the outside universe around a satellite and the rotational pull of the Earth below it both get to influence the choice of rotational frame that the satellite's gyros sense as “non-rotating”, and if both “bodies” get to “vote” on this choice of frame according to their contribution to the amount of gravitational flux at the satellite's position, then if we know that ratio, we can calculate the final GPB result as a back-of-an-envelope calculation ("A Journey into Gravity and Spacetime (http://www.worldcat.org/search?q=0716760347)", J.A. Wheeler 1999, p.232-233).

Where the alternative model differs from GR is that it doesn't make a distinction between “gravitational” and “non-gravitational” bodies, it says that if you get close enough, the same effects ought to show up for anything (a tennis ball, a potato, a spaceship). For the “linear acceleration” and “centrifugal field” cases, this doesn't look like a big deal. We can probably get away with applying these to small objects under current theory, and say that since they involve geeforces, if the results ever seem to conflict with special relativity, it's not SR's fault (since SR wasn't derived to “do” gravitation or the Equivalence Principle, or to apply the principle of relativity to noninertial motion).

Where the two models diverge more unambiguously is with the extension of the third case, the “Coriolis” field, to small objects.
If we go back to the case of a rotating body, the receding redshifted parts of the body appear to pull more strongly than the approaching blueshifted parts, even when those parts are otherwise identical. So the Coriolis component suggests the existence of velocity-dependent dragging effects between mass