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On May 26, 2011, at 2:41 PM, Paul Zielinski wrote:

On 5/25/2011 8:09 PM, JACK SARFATTI wrote:

On May 25, 2011, at 7:37 PM, Paul Zielinski wrote:

On 5/25/2011 6:02 PM, JACK SARFATTI wrote:

If the measuring rod really contracted in the direction of zero g-force uniform motion this would cause asymmetric strains in the material of the rod and cause tidal distortions in the uniformly moving observer relative to the absolute global rest frame - clearly this is complete nonsense.

Well then so much for John Bell's "Lorentzian pedagogy"!

Exactly, it may have been his greatest blunder!

Well maybe you do have a point here.

But inertially moving clocks could be regarded as physically slowing down, according to the Lorentz transformations, and then length
contraction could be derived from the apparent changes in physical simultaneity (i.e. simultaneity defined by synchronization of the
actual readings shown by moving physical clocks) from end to end of an inertially moving measuring rod, in manner analogous to
orthodox SR, right?

I don't see how the relativity of simultaneity suffices to justify the Lorentzian-Fitzgerald-Bell approach. If you say the rod really shrinks or the clock really slows down relative to some global Galilean frame of absolute rest, then unless there is some way to measure that contraction/dilation intrinsically in the rest frame of the moving detector - the theory is baloney.is

Of course we can measure clock retardation.

We measure time dilation in the half-life of cosmic ray muons for example. Sure. But that is a frame-covariant effect. It's perfectly symmetrical. That is, detectors moving with the cosmic ray shower would show the same time dilation for muons at rest in the Earth frame. There is no way to locally intrinsically measure the absolute velocity of an object in its rest frame relative to the alleged global rest frame. This is unlike locally measuring curvature in an LIF for example. However, we can measure the "absolute", more precisely the "peculiar velocity" relative to the Hubble flow using the CMB anisotropy and the absolute time using the CMB BB temperature in cosmology - a spontaneous breakdown of Poincare group symmetry in the vacuum solution - the field equations are still locally Lorentz sub-group invariant.

The *physical model* that we have adopted tells us what we are measuring. In the Einstein model,
we are measuring kinematical time dilation. In Poincare-Lorentz, we are measuring physical clock retardation. Either way, the *appearance* of length
contraction results from *observed* shifts in simultaneity as you go from one inertial frame to another.

In the Poincare-Lorentz model, we are simply judging simultaneity using uncorrected physically retarded clock readings, but that is enough to get
agreement with the observations.  If you correct the clock readings for the objective physical effects of inertial motion, then you recover Galilean
*kinematical* simultaneity in this model. Of course that doesn't apply to the Einstein model, where the kinematics directly reflects the readings of
the moving clocks (assuming the clocks are otherwise "good").

It's not good physics because there is no operational procedure to falsify "the rod really contracts in its direction of absolute uniform zero g-force motion" or, similarly "the clock really slows down"

But neither is there any operational procedure to falsify the proposition "space contracts" or, similarly, the proposition "time slows down", in
the observer's inertial frame of reference. So the choice between models cannot be decided on such operational grounds alone.

Again, I'm not arguing this as a fundamental theory, just as an engineering model. Or a "pedagogy", if you prefer.

Again think of the Ricci compressions and the Weyl tidal distortions that even can be detected locally and intrinsically in a LIF - it would have to be something like that!
We can measure clock retardation in the Poincare-Lorentz model. As Einstein famously said to Heisenberg (in the1926 conversation about Einstein's own 1905 paper), "It
is the theory that tells you what can be measured".

Something is "real" only if it's (local) frame "gauge" covariant from which invariants can be computed. Therefore the shrinkage and dilation must be intrinsically measurable even in the rest frame of the allegedly really moving rod/clock - just as tensor curvature is real.
Well I agree, but isn't that the point of objective clock retardation? That it is an objective physical effect?

In the Minkowski spacetime geometry, the invariant spacetime interval s determines the times read by moving clocks. It is represented
by a Lorentz tensor. If one interprets Minkowski spacetime in terms of a Poincare-Lorentz type model, the Lorentzian metric can be
understood as a geometric representation of the objective slowing of clocks in inertial motion. In a generally covariant formulation of
Minkowski's spacetime geometry, the invariant interval becomes a general tensor.

Doesn't that overcome your objection?

Note, that in cosmology there is the global rest frame of the Hubble flow in which the CMB is maximally isotropic to 1 part in 10^5 in the sense of WMAP etc.
Right. There is a natural choice for a global rest frame in modern cosmology.
But this is a spontaneous breakdown of the vacuum Lorentz group analogous to the Heisenberg ferromagnet for the rotation group, the field equations are still dynamically invariant under the Lorentz group for locally coincident LIF --> LIF' maps e.g. the tetrads e^I are Lorentz group 4-vectors.
Well if you have a set of Lorentz transformations under which the laws of physics are invariant, then you have a Lorentz
group. But this applies in both the Einstein and Poincare-Lorentz models for Minkowski SR.  Only the physical interpretation
of the Lorentz transformations is different.

Then there would be no need for actual physical compression in the model, only for the actual universal slowing of clocks.

Word salad. This is mere word play. If you can't tell an experimental physicist how to measure it, it ain't good physics. It's what Feynman meant by "philofawzy".

I'm just saying there is no need for actual length contraction in either model. 

The point here Jack is that it is the physical model that is adopted that tells you what you are measuring with you operational procedures.
Einstein himself understood this by 1926:

"For the first time, therefore, I now had the opportunity to talk with Einstein himself. On the way home, he questioned me about my background, my studies with Sommerfeld. But on arrival, he at once began with a central question about the philosophical foundation of the new quantum mechanics. He pointed out to me that in my mathematical description the notion of electron path' did not occur at all, but that in a cloud chamber the track of the electron can of course be observed directly. It seemed to him absurd to claim that there was indeed an electron path in the cloud chamber, but none in the interior of the atom. The notion of a path could not be dependent, after all, on the size of the space in which the electron's movements were occuring. I defended myself to begin with by justifying in detail the necessity for abandoning the path concept within the interior of the atom. I pointed out that we cannot, in fact, observe such a path; what we actually record are frequencies of the light radiated by the atom, intensities and transition probabilities, but no actual path. And since it is but rational to introduce into a theory only such quantities as can be directly observed, the concept of electron paths ought not, in fact, to figure in the theory.
"To my astonishment, Einstein was not at all satisfied with this argument. He thought that every theory in fact contains unobservable quantities. The principle of employing only observable quantities simply cannot be consistently carried out. And when I objected that in this I had merely been applying the type of philosophy that he, too, has made the basis of his special theory of relativity, he answered simply: 'Perhaps I did use such philosophy earlier, and also wrote of it, but it is nonsense all the same.'... ...He pointed out to me that the very concept of observation was itself already problematic. Every observation, so he argued, presupposes that there is an unambiguous connection known to us, between the phenomenon to be observed and the sensation which eventually penetrates into our consciousness. But we can only be sure of this connection, if we know the natural laws by which it is determined. If, however, as is obviously the case in modern atomic physics, these laws have to be called into question, then even the concept of "observation" loses its clear meaning. In that case, it is the theory which first determines what can be observed."


The Lorentz- Fitzgerald contraction would then be reduced to an epiphenomenon of physical time dilation. In this respect a Poincare-Lorentz type
model would thus follow exactly the same approach as Einstein SR. Wouldn't that overcome your objection?

No, because your sentences make no sense to me. They sound good, but I see no meaning to them.
Isn't it the case that in Einstein's model, length contraction is an epiphenomenon of relativistic time dilation? Isn't it the case that in Einstein's 1905
theory, length contraction is only apparent, while physical time actually slows down relative to the observer's inertial frame of reference?

I think this is the position taken in several textbooks. French's "Special Relativity", for example.


Remember, we're talking about an engineering model here, not fundamental theory. I'm still assuming that the fundamental theories
here are orthodox SR and orthodox GR.

This strain asymmetry in uniform zero-g force motion would be analogous to the Ricci and Weyl curvature distortions that are detectable on timelike geodesics.

Therefore, I do not think the objective distortion idea can work.

OK, but what about deriving it from changes in physical simultaneity due to the objective physical behavior of moving clocks?

Again this is word salad.

But you said that "real" physical quantities should transform as tensors. Doesn't the objectivity of inertial clock retardation in the Poincare-Lorentz
model naturally result in tensor invariance in a 4D spacetime geometric representation? 

You are misusing "objectivity." Sure the half-life of unstable particles is frame-covariant just like measuring components of the EM field tensor Fuv is frame-covariant and frame invariants can be constructed from the raw data.

If the observer at rest with the absolutely moving clock cannot locally detect his absolute motion then it's not good physics.

So you disagree with Einstein in the quote above, where he reportedly says to Heisenberg, "... every theory in fact contains unobservable
quantities. The principle of employing only observable quantities simply cannot be consistently carried out..."?

Not at all. That does not follow from what I have written. I agree with Einstein obviously. I say ALL local observables must be frame-covariant like Fuv for example with respect to the global (and localized) dynamical symmetries (with compensating spin 1 gauge connections), with the proviso, that some of these local symmetries may be spontaneously broken in the vacuum spacetime continuum. Also, we are restricted by the local light cones as well as the global light-like horizons (e.g. the Susskind papers)- unless we have post-quantum signal nonlocality, but that is largely uncharted territory still. Also I am neglecting smearing of the light cones from alleged quantum gravity.

Note we can detect peculiar motion relative to the Hubble flow of the expanding accelerating universe from the anisotropy in the CMB and we can measure absolute time from the CMB temperature.


Where the distance  between the endpoints of an inertially moving rod "at the same time" depends on the physical behavior of the clocks? In other words, length
contraction would be an artifact of using moving physical clocks to determine simultaneity according to the usual synchronization procedures?

I have no idea what your sentence means physically. You seem to be going round in circles.

I'm talking about simultaneity judged using inertially moving clocks and the standard Poincare-Einstein synchronization procedure. If the clock
readings are taken at face value, then simultaneity *appears* to change with the observer's inertial frame in the 1905 Poincare model, just as it
does in the 1905 Einstein model.

We are talking about different things here. My point is that if you cannot measure the effect in a LIF it is not real. More specifically, if one claims there is an absolute rest frame and if there is no way to measure uniform motion relative to it, then it is not real physically. Of course, in cosmology, this particular effect is real from the spontaneously breakdown of time translation and boost symmetry - this is ultimately a non-classical quantum effect appended to classical relativity.

In the Poincare model, the clocks actually slow down -- it's an objective physical effect -- and that is accounted for in Minkowski's 4D spacetime
geometry by the (tensor) invariance of the spacetime interval. On the other hand there is nothing in Einstein's 1905 theory to physically account
for such invariance. From the Einstein 1905 POV, this pops up out of nowhere.

Interestingly, Minkowski himself commented on this.

Isn't that essentially what we do in orthodox SR? Isn't it the frame-dependent changes in simultaneity from point to point that result in length
contraction in SR?

That's the point. Length contraction is not real in orthodox SR it's an optical illusion from the finite speed of light and the Lorentz group.


I'm saying that the situation regarding length contraction would be essentially the same in a Poincare-Lorentz type model. I'm saying there is no more
need for actual contraction in such a model than there is in the Einstein model for SR.
To the guy on the moving meter stick it still is a meter. Similarly, for the ticking of the clock. Of course, we measure time dilation in the cosmic mu meson experiment etc., but that does not contradict my point here.

So in either theory all we need is universal inertial clock retardation. In Einstein's 1905 theory, the retardation is kinematical;
in the Poincare-Lorentz approach, the retardation is dynamical.
Another example, is that a moving rod actually appears to rotate not contract when you do the problem correctly.

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OK, so you agree that there is no actual length contraction in Einstein's 1905 model. I'm saying there is no need for it in a Poincare-Lorentz
type model either.

Remember, there are no detectable distortions of measuring rods and clocks on timelike geodesics for observers at rest with respect to them.

On May 25, 2011, at 5:50 PM, Paul Zielinski wrote:

On 5/25/2011 5:32 PM, JACK SARFATTI wrote:

On May 25, 2011, at 5:17 PM, Paul Zielinski wrote:

On 5/25/2011 5:03 PM, JACK SARFATTI wrote:

On May 25, 2011, at 4:46 PM, Paul Zielinski wrote:

Well, how did we get along without 4 tensors in Newtonian gravity?

Newton's theory does not have a good theory of measurement. It cannot correctly tell you what locally coincident detectors measuring the same events will record.

So for example if we have a pair of coincident accelerometers moving in different accelerating frames, non-covariantly formulated Newtonian theory in
3D space doesn't allow us to predict the readings of the accelerometers, given some source mass M at some location x?

Well we have to use the Galilean group, so if v/c << 1 for the detectors, I suppose within that approximation one will get a decent answer.
But in Hal's PV there is no effective procedure or algorithm to even answer your question. If there is then Hal will show us how.

OK fair enough, we would of course have to invoke Lorentz transformations, either in a Poincare-Lorentz or an Einsteinian framework. Poicare-Lorentz
is known to give all the same predictions as Einstein's approach, but would be a better match with the PV model which as I understand it attributes the
metrical effects of gravity to the objective physical distortion of the measuring instruments.

Either way agreed you need Lorentz transformations to get accurate predictions unless v << c. But I still don't see why you need a 4D tensor formalism.
After all, there was no 4D spacetime in Einstein's non-covariant 1905 model, was there?

Or in the classical optics of refractive media?

The old equations only work in the rest frame of the material.

Are you saying you can't predict and allow for the effects of observer frame transformations on the comoving detector readings
without going to a 4D tensor formalism?

You cannot predict correctly when v/c ~ 1 and the locally coincident detectors are accelerating.
OK but you can if you attribute the high velocity effects to objective motion-dependent physical changes in the measuring instruments,
correct? I'm not saying that one necessarily *should* do this, just that if this is done you do get accurate predictions from a set of Lorentz-
type transformations without the use of tensors -- as per Poincare-Lorentz 1905-6.

Even Einstein, who bundled the Lorentz transformations into the kinematics using coordinate frames, didn't need tensors to get accurate

And doesn't PV assume flat reference geometry for the kinematics? With objective gravitational distortion
of physical measuring rods?

Ask Hal.

In the PV model, does the lack of general covariance imply that this flat reference geometry is not invariant
under general frame transformations?

Ask Hal.

On 5/25/2011 4:36 PM, JACK SARFATTI wrote:

On May 25, 2011, at 4:26 PM, Paul Zielinski wrote:

But this is only needed if you go to a 4D representation of motion. There is no practical need for 4-tensors
in a 3D + 1 representation. And if I understand it correctly, PV is a 3D + 1 model for gravity.

No that is wrong. See the ADM formulation for example.
also you completely miss the physics i.e.

The tensor and spinor maps allow you to write the same intrinsic geometry in terms of LNIFs on arbitrary timelike worldlines.

Of course you *can* reformulated a pre-Einstein 3D + 1 model (such as Newton's theory) in a covariant
4D framework, but there is no practical need to do it if we are only interested in using the model for
engineering purposes. We can still make predictions regarding the effects experienced by moving
detectors just as we can in traditional Newtonian physics.

Are you saying that a 4D covariant tensor formulation is needed for that? Or just that it makes things
neater from a mathematical perspective?

On 5/25/2011 4:06 PM, JACK SARFATTI wrote:
For example
if you write a formal expression such as

g00 = 1 - rs/r  for rs/r < 1  et-al


g00' = 1 - /\r^2  et-al

for a detector at r = 0

these representations are shadows on the wall of Plato's Cave where the Platonic form or Idea is the invariant

ds^2(r) = guv(LNIF)dx^udx^v = nIJ(LIF)dx^Idx^J

the above representations are only valid for a class of hovering static LNIF detectors whose world lines are not timelike geodesics.

The tensor and spinor maps allow you to write the same intrinsic geometry in terms of LNIFs on arbitrary timelike worldlines.

On May 25, 2011, at 3:54 PM, JACK SARFATTI wrote:

On May 25, 2011, at 3:42 PM, Paul Zielinski wrote:

I'm not trying to sell you on PV. I'm just suggesting that the *purpose* of the the toy model developed by
Thorne et al. is very similar to Hal's purpose in developing his PV "engineering model" for GR.

Perhaps, but Kip's model agrees with observation and Hal's does not.

Agreed that Hal's version of PV is not tensor covariant, but I will say that since it is a purely mathematical
exercise to render any reasonable physical theory into fully covariant form, I don't see this as a fundamental

No, here is the physical point you miss. What tensor and spinor formal transformations mean physically when combined with the EEP tetrad map is how locally coincident detectors data may be computed to get invariants on simultaneous local measurements of the same set of events, e.g. photons from a distant pulsar etc.
Therefore, Hal's PV model does not have a clear theory of measurement of its fundamental observables.

I imagine that the Thorne model has very similar limitations to the PV model.

Not as far as I know.

I'm not sure that "Popper falsifiability" is directly relevant to an approximate "engineering" model which as
such is subject to purely pragmatic criteria. After all, NASA continues to use Newtonian gravitational theory
as an "engineering model" for the computation of satellite orbits, and I doubt that the engineers at NASA are
concerned that Newton's theory has been deemed to have been "falsified" in favor of GR -- as long as the
accuracy of the predictions is sufficient for engineering purposes.

Well you need GR for GPS positioning for example. That's very pragmatic.

On 5/25/2011 2:42 PM, JACK SARFATTI wrote:
The basic defects in Hal's model in my opinion are:

1) not local frame covariant - no tensors

2) no event horizons - all of modern relativity assumes horizons and t' Hooft-Susskind hologram approach depends on it "causal diamond" et-al - Uruh effect, Hawking radiation

3) falsified by data

4) can't do rotating masses

But at least it was Popper falsifiable.

On May 25, 2011, at 2:07 PM, JACK SARFATTI wrote:

Maybe- but I gave you the mechanism below why it works.

It has to do with virtual electron-positron pairs at the horizon similar to Stephen Hawking's picture leading to Hawking-Unruh thermal radiation from the acceleration of the virtual pairs "stuck" to the horizon membrane as static LNIFs i.e.

covariant acceleration of a static LNIF = (Newtonian gravity "force" acceleration)/g00^1/2 ---> infinity at a horizon where g00 ---> 0

therefore an enormous Unruh temperature that pulls virtual electron-positron pairs into real electron-positron pairs one falls down the black hole, the other escapes to us.

PS to model the constant force acceleration of the universe requires for static LNIFs inside the cosmological future horizon (outside a black hole horizon in that dual case)

g00' = 1 - /\^1/2r

rather than the de Sitter

g00 = 1 - /\r^2

On May 25, 2011, at 2:01 PM, Paul Zielinski wrote:

But this is merely a classical working model, right? Of an inherently quantum mechanical phenomenon?

In this respect similar in purpose to Hal Puthoff's PV model?

On 5/25/2011 10:53 AM, JACK SARFATTI wrote:
As I understand it. Kip's idea applies to neutral Schwarzschild and Kerr black holes without any real net external charge. It has to do with                                                           virtual electron-positron pairs at the horizon similar to Stephen Hawking's picture leading to Hawking-Unruh thermal radiation from the acceleration of the virtual pairs "stuck" to the horizon membrane as static LNIFs i.e.

covariant acceleration of a static LNIF = (Newtonian gravity "force" acceleration)/g00^1/2 ---> infinity at a horizon where g00 ---> 0

therefore an enormous Unruh temperature that pulls virtual electron-positron pairs into real electron-positron pairs one falls down the black hole, the other escapes to us.

Membrane paradigm
From Wikipedia, the free encyclopedia
In black hole theory, the black hole membrane paradigm is a useful "toy model" method or "engineering approach" for visualising and calculating the effects predicted by quantum mechanics for the exterior physics of black holes, without using quantum-mechanical principles or calculations. It models a black hole as a thin classically-radiating surface (or membrane) at or vanishingly close to the black hole's event horizon. This approach to the theory of black holes was created by Kip S. Thorne, R. H. Price and D. A. Macdonald.
The results of the membrane paradigm are generally considered to be "safe".
Contents  [hide]
1 Electrical resistance
2 Hawking radiation
3 See also
4 References
[edit]Electrical resistance

Thorne (1994) relates that this approach to studying black holes was prompted by the realisation by Hanni, Ruffini, Wald and Cohen in the early 1970's that since an electrically charged pellet dropped into a black hole should still appear to a distant outsider to be remaining just outside the critical r=2M radius, if its image persists, its electrical fieldlines ought to persist too, and ought to point to the location of the "frozen" image (1994, pp.406). If the black hole rotates, and the image of the pellet is pulled around, the associated electrical fieldlines ought to be pulled around with it to create basic "electrical                                                           dynamo" effects (see: dynamo theory).
Further calculations yielded properties for a black hole such as apparent electrical resistance (pp.408). Since these fieldline properties seemed to be exhibited down to the event horizon, and general relativity insisted that no dynamic exterior interactions could extend through the horizon, it was considered convenient to invent a surface at the horizon that these electrical properties could be said to belong to.
[edit]Hawking radiation