EM Drive Developments Thread 1

[Mulletron]

* Woodward, having an internally consistent theory (though I wouldn't put any money on it), being an exception to this.

Except Woodward's theory relies on magic Machian inertia, "gravinertial flux" and "Flux Capacitors"....And ignores recent scientific observations showing anisotropy of the CMB, yet there is no anisotropic inertia. And his theory/thrusters have never been reproduced outside his own lab. Did I mention that Mach is so old school that he didn't believe in atoms? Did I mention that Machian inertia is so generalized, that it makes no actual predictions? Sometimes you just gotta let it go already, unless you wanna sell some books.

If you want to fisk someone's post, rather than putting your comments in blue, I suggest you use the '[/quote' your comment '[quote' method as that way it's clear who's talking.

Can you explain in what way CMB anisotropy would imply inertial aniosotropy under Machian effects?

The anisotropies of the CMB shouldn't affect inertia unless they are on the size scale of the observable universe.

Indeed the CMB is the limit of the observable universe. It is a barrier you can't see past. It has structural anisotropy and a dipole anisotropy. Here's some more info:
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.112.582
http://www.haverford.edu/physics/dcross/research/papers/oral.pdf
http://en.wikipedia.org/wiki/Hughes%E2%80%93Drever_experiment
http://en.wikipedia.org/wiki/Cosmic_microwave_background#CMBR_dipole_anisotropy
http://link.springer.com/article/10.1007%2FBF02859800
http://arxiv.org/pdf/1307.2637.pdf

[Rodal]

There is at least one discussion of this in Barbour and Pfister, in the piece by Hans Reissner on "Relativity of Accelerations in Mechanics", on page 144, but I don't think this is the issue you think it is.  Inhomogeneity does not beget anisotropy.  Keep in mind that according to Mach, it is not the closest masses that most affect local inertia it is those that are farthest away.  Still, there was this debate in the early teens with Schrodinger and Reissner and you'll find it referenced in Barbour & Pfister.  Schrodinger's response is immediately following.

B&F is truly the indispensable source for understanding Mach's Principle in its historic context.  However, also see:

"Mach's relativity of inertia does not necessarily imply an anisotropy of inertial masses in an anisotropic universe and the Mach-Einstein doctrine is compatible with the isotropy of mass in each cosmos."

http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1992AN....313...65T&db_key=AST&page_ind=0&data_type=GIF&type=SCREEN_VIEW&classic=YES

Concerning your statement <<Inhomogeneity does not beget anisotropy>> , nobody said that inhomogeneity begets anisotropy (it is well known that most isotropic bodies are isotropic due to the small scale and randomness of their anisotropy).

Mullet's observation was concerning the established anisotropy of the CMB.  What I wrote was: <<The temperature variations have been measured as (at most) plus or minus 0.00335 K variation with one hot pole and one cold pole. >> that refers to the dipole established by the difference in temperature between the hot pole and the cold pole of the CMB: this clearly established a (very small, as I remarked) anisotropy.  We are not discussing here some hypothetical effect [as in Cocconi and Salpatz (1958) discussed below], we are discussing Mullet's observation concerning the anisotropy of the CMB due to this dipole.

Concerning the 1992 paper by Treder you quote, it does not address at all the established anisotropy of the CMB, it discusses instead a) the problem of the masses in the universe being at different distances (near and distant mass attractors) from a given object whose inertia we are interested in, and b) the hypothetical ansatz of Cocconi and Salpatz (1958) (a different hypothetical inertial field ansatz in addition to the Newtonian field) . 

Therefore your quotation of Treder is not applicable to the CMB anisotropy issue referred to by Mullet's excellent observation.

The issue referred to by Mullet should rather be addressed in terms of an integration (over all directions)  which will show it to be of a very small nature (as remarked previously) perhaps beyond any experimental inertial measurement conducted up to now (?) regarding different orientations.  It may be small, but it is not non-existent.  The anisotropy of the CMB is something that cannot be denied. It may be very small (some sources say one part in 100,000 according to how you measure it) but it took four years to map the  anisotropy of cosmic background radiation as it was the only instrument not dependent on the dewar’s supply of helium to keep it cooled, and nobody denies its existence.

Thus, Mullet presents a very interesting experiment (if it could be conducted to the required precision) from which, perhaps one could establish the validity (or non-validity) of Machian inertia.

[Mulletron]

Thank you for posting this. We all dream to see this with our own eyes, if only...

[Ron Stahl]

Therefore your quotation of Treder is not applicable to the CMB anisotropy issue referred to by Mullet's excellent observation.

I guess then, I must confess I don't understand the point.  The gravitational field of the universe, that gives matter its mass and is the cause of inertia, is in no way connected to the thermal distribution of the CMB.  The CMB loosely corresponds to the mass distribution of the universe, so I presumed this is what you were both speaking of.  The present thermal distribution is however, beside the point so far as I can see.

I thought you were both referring to the inhomogeneities in the gravitational field one would suppose is there when one notes the inhomogeneities in the CMB.  Now you have said more than once you're more specifically talking about the thermal background, and I confess I don't see how this pertains apart from how it illustrates the mass background.

I'll be away Sunday so please don't take it as a slight that you spank me good here and I disappear.  I am looking forward to learning what you two are saying.  Bon weekend.

[Rodal]

Therefore your quotation of Treder is not applicable to the CMB anisotropy issue referred to by Mullet's excellent observation.

I guess then, I must confess I don't understand the point.  The gravitational field of the universe, that gives matter its mass and is the cause of inertia, is in no way connected to the thermal distribution of the CMB.  The CMB loosely corresponds to the mass distribution of the universe, so I presumed this is what you were both speaking of.  The present thermal distribution is however, beside the point so far as I can see.

I thought you were both referring to the inhomogeneities in the gravitational field one would suppose is there when one notes the inhomogeneities in the CMB.  Now you have said more than once you're more specifically talking about the thermal background, and I confess I don't see how this pertains apart from how it illustrates the mass background.

I'll be away Sunday so please don't take it as a slight that you spank me good here and I disappear.  I am looking forward to learning what you two are saying.  Bon weekend.

1) Essentially, the Treder quotation refers to outdated astrophysical data from 1964 and 1961, (Hughes and Drever: their actual experiment probing only the quadrupolar anisotropy) to quantify his alpha and beta in his equations that lead him to disregard anisotropy.  Up to date astrophysical data is needed, not these astrophysical data that is more than 50 years old.

2) Also a newer reference is needed regarding an up to date ansatz for the anisotropy of the most distant bodies responsible for Machian inertia. The ansatz dealt with by Treder, including the hypothetical (multiple) ansatz proposed by Cocconi is not longer relevant.

3) As you know, Machian principle determines the inertia of bodies, in a way that the heavy and distant bodies of our universe contribute the most to the inertial forces, thus anisotropy of the most distant bodies matters most. The most distant bodies that we are able to measure are also the ones that are most distant in time (closer in time to the Big Bang) since light took longer to contact us.

[Rodal]

Therefore your quotation of Treder is not applicable to the CMB anisotropy issue referred to by Mullet's excellent observation.

I guess then, I must confess I don't understand the point.  The gravitational field of the universe, that gives matter its mass and is the cause of inertia, is in no way connected to the thermal distribution of the CMB.  The CMB loosely corresponds to the mass distribution of the universe, so I presumed this is what you were both speaking of.  The present thermal distribution is however, beside the point so far as I can see.

I thought you were both referring to the inhomogeneities in the gravitational field one would suppose is there when one notes the inhomogeneities in the CMB.  Now you have said more than once you're more specifically talking about the thermal background, and I confess I don't see how this pertains apart from how it illustrates the mass background.

I'll be away Sunday so please don't take it as a slight that you spank me good here and I disappear.  I am looking forward to learning what you two are saying.  Bon weekend.

1) Essentially, the Treder quotation refers to outdated astrophysical data from 1964 and 1961, (Hughes and Drever: their actual experiment probing only the quadrupolar anisotropy) to quantify his alpha and beta in his equations that lead him to disregard anisotropy.  Up to date astrophysical data is needed, not these astrophysical data that is more than 50 years old.

2) Also a newer reference is needed regarding an up to date ansatz for the anisotropy of the most distant bodies responsible for Machian inertia. The ansatz dealt with by Treder, including the hypothetical (multiple) ansatz proposed by Cocconi is not longer relevant.

3) As you know, Machian principle determines the inertia of bodies, in a way that the heavy and distant bodies of our universe contribute the most to the inertial forces, thus anisotropy of the most distant bodies matters most.  The most distant bodies that we are able to measure are also the ones that are most distant in time (closer in time to the Big Bang) since light took longer to contact us. 

4) This 2004 paper attempts to address Mullet's observation concerning the CMB anisotropy and goes further than Treder :

Anisotropy of Inertia from the CMB Anisotropy
Daniel J. Cross


http://www.haverford.edu/physics/dcross/research/papers/oral.pdf

but the conclusion readily admits that it is incomplete

It is regrettable that this project remains uncompleted at this point. The framework has
been laid above, but there are several steps left before completion. Its has been shown that
an inertial mass that depends arbitrarily on direction is a priori possible, the dependence
presumably arising from an interaction with anisotropic matter at great distances, in the
spirit of Mach's Principle. Even though the angular dependence is quite general, the pos-
sible couplings to matter in experiments of the Hughes-Drever type is severely restricted,
their actual experiment probing only the quadrupolar anisotropy. Based on their experi-
ment a limit was set on the quadrupolar term in the inertial mass anisotropy. It remains to
compare expansion coe±cients between the inertial mass and matter anisotropy at great
distance through the WMAP data of the CMB. From this comparison, limits can be set on
higher coe±cients to see whether these multipoles are accessible to observation. Finally,
it is desirable to propose a speci¯c coupling scheme between local inertia and distant mat-
ter, possibly through 1=R type interaction. In this manner it may be possible to predict
absolute values of the local multipole coe±cients, and therefore be more certain that the
Hughes-Drever tests have actually ruled out such anisotropy or are yet too insensitive.

I expect that Machian inertia researchers should have already addressed this issue more in depth and up-to-date than what I have seen, as it is important to completely address anisotropy of inertia vis-a-vis experiments to validate their theory.  Therefore I hope that the backers of Machian inertia can uncover better and up-to-date references to properly address the excellent point brought up by Mulletron.

[frobnicat]

I'm loosing feet with what is going on here with ME vs EM. Regarding the former, I understand Ron states it is not incompatible with GR, so not with SR, so not with Lorentz invariance. But it can predict the result of a situation that GR cannot predict, namely situation of a ME thruster thrusting. This "hole" in GR was never noticed because such prediction for such situation never needed, kind of, so possible Machian "extension" (?) to GR forgotten. How could it be that a mundane device like a ME thruster could leave classic frameworks GR + QFT voiceless ?

This is not a problem of interpretation but of prediction, the two classical frameworks GR+QFT (which show no practical incompatibilities when dealing with meso-scale, low energies, low background curvatures) surely would tell the magnitude of the thrust, and that the net thrust is equal or bellow spent_power/c, or more simply 0 if nothing is expelled (no matter, no radiation). I can't see how this very specific device (ME thruster) could leave the equations of GR+QFT befuddled to the point of being unable to be solved or converge clearly on some definite answer. And this answer would be in contradiction with claimed thrust/power that ME theory seems to allow. So it could be that ME theory is more general than GR in the same sense that GR is more general than Newtonian dynamics. GR would have a limited range of validity (all that has been uncontroversially observed and measured accurately so far within mesoscale) and ME theory a bigger one (all that has been uncontroversially observed and measured accurately so far within mesoscale + ME thruster thrusting at thrust/power>1/c). Note that a ME thruster is clearly mesoscale. Not speaking here of wide or dense objects, yet to be accurately observed and characterised in their constitution (like galaxies, gravitationally collapsed bodies...). Anyhow, wouldn't say that GR is "compatible" with Newtonian dynamics. B is compatible with A if B has the same answers as A whenever A answers at all. Or would Machian effect proponents say that GR is only an approximation, valid only in a certain "range", and that can be shown as a limit in this range of a more general Machian physics (B says the same thing as A for a limited configuration space, and a different thing outside) ?

Be assured this is my writing which is confused, not your reading.

Back to the subject, assuming a Machian physics is compatible with SR, that would make the dipole moment of CMB irrelevant, this is (very most likely...) due to our contingent velocity in the bath. Put a rocket at velocity relative to sun (around 370km/s, easy)  and the dipole vanishes. And the same experiments onboard that rocket give exact same results as those on earth labs (interactions with local bath excluded). That's what SR tells (Newtonian also), so this is what a SR compatible Machian physics would tell also. Such Machian physics couldn't be falsified by the absence of inertia anisotropy in spite of dipole moment.

As for the higher order anisotropies... this looks like a nice playground, full of hills and hollows. What a GR compatible Machian physics would have to say different from what would say GR : local inertias don't care ? Anyway, it claims to predict an effect that is astounding for most people working with GR under the form of a ME thruster thrusting. Can't the theory devise one other type of experiment that is at least as astounding and that could lend itself to more convincing reproducible results ? Call it an experiment in fundamental science (à la Michelson and Morley). Better credibility to the theory if it can expose itself to experimental falsifiability on other grounds that notoriously capricious propellentless drives. Are there such other falsifiable grounds ?

[Rodal]

I'm loosing feet with what is going on here with ME vs EM. Regarding the former, I understand Ron states it is not incompatible with GR, so not with SR, so not with Lorentz invariance. But it can predict the result of a situation that GR cannot predict, namely situation of a ME thruster thrusting. This "hole" in GR was never noticed because such prediction for such situation never needed, kind of, so possible Machian "extension" (?) to GR forgotten. How could it be that a mundane device like a ME thruster could leave classic frameworks GR + QFT voiceless ?

This is not a problem of interpretation but of prediction, the two classical frameworks GR+QFT (which show no practical incompatibilities when dealing with meso-scale, low energies, low background curvatures) surely would tell the magnitude of the thrust, and that the net thrust is equal or bellow spent_power/c, or more simply 0 if nothing is expelled (no matter, no radiation). I can't see how this very specific device (ME thruster) could leave the equations of GR+QFT befuddled to the point of being unable to be solved or converge clearly on some definite answer. And this answer would be in contradiction with claimed thrust/power that ME theory seems to allow. So it could be that ME theory is more general than GR in the same sense that GR is more general than Newtonian dynamics. GR would have a limited range of validity (all that has been uncontroversially observed and measured accurately so far within mesoscale) and ME theory a bigger one (all that has been uncontroversially observed and measured accurately so far within mesoscale + ME thruster thrusting at thrust/power>1/c). Note that a ME thruster is clearly mesoscale. Not speaking here of wide or dense objects, yet to be accurately observed and characterised in their constitution (like galaxies, gravitationally collapsed bodies...). Anyhow, wouldn't say that GR is "compatible" with Newtonian dynamics. B is compatible with A if B has the same answers as A whenever A answers at all. Or would Machian effect proponents say that GR is only an approximation, valid only in a certain "range", and that can be shown as a limit in this range of a more general Machian physics (B says the same thing as A for a limited configuration space, and a different thing outside) ?

Be assured this is my writing which is confused, not your reading.

Back to the subject, assuming a Machian physics is compatible with SR, that would make the dipole moment of CMB irrelevant, this is (very most likely...) due to our contingent velocity in the bath. Put a rocket at velocity relative to sun (around 370km/s, easy)  and the dipole vanishes. And the same experiments onboard that rocket give exact same results as those on earth labs (interactions with local bath excluded). That's what SR tells (Newtonian also), so this is what a SR compatible Machian physics would tell also. Such Machian physics couldn't be falsified by the absence of inertia anisotropy in spite of dipole moment.

As for the higher order anisotropies... this looks like a nice playground, full of hills and hollows. What a GR compatible Machian physics would have to say different from what would say GR : local inertias don't care ? Anyway, it claims to predict an effect that is astounding for most people working with GR under the form of a ME thruster thrusting. Can't the theory devise one other type of experiment that is at least as astounding and that could lend itself to more convincing reproducible results ? Call it an experiment in fundamental science (à la Michelson and Morley). Better credibility to the theory if it can expose itself to experimental falsifiability on other grounds that notoriously capricious propellentless drives. Are there such other falsifiable grounds ?

Great points, including the fact about the dipole moment being irrelevant [initially I had to think about that one, thank you] and the higher order anisotropies being the relevant ones -for discrimination-. 

the matter distribution around us exhibits clumping which is understood as
Gaussian quantum fluctuations that were stretched into real density perturbations by
the expansion of the universe. Such perturbations in the matter distribution lead to
gravitational perturbations that alter the temperature of photons through redshift and
time dilation. This is known as the Sachs-Wolfe effect and dominates the anisotropy at
large scales. The next contribution to the anisotropy comes from Doppler shifting which does not contribute appreciably until l >30

In this work it is shown that there are some spatially homogeneous
but anisotropic models (Kantowski-Sachs and Bianchi type-III), with a positive
cosmological constant, for which the inhomogeneities in the distribution of matter on
the surface of the last scattering produce anisotropies (in large angular scales # »> 10±)
that do not di®er from the ones produced in Friedmann-Lemaitre-Robertson-Walker
(FLRW) models, if the density parameters are finely tuned.

[Mulletron]

Plenty of atmo here in NYC. Thought about how it pushes on me, like Mull's QV. If I wanna go thru the atmo w/o expelling propellant, I gotta use a propeller. Mull, yer gonna have to come up with a propeller.  And then we can all start calling it the aether.

What I'm describing is called a differential sail, more specifically an induction sail, which is/was a hypothetical concept theorized by Marc G. Millis. It just hasn't been realized, until......now? Time will tell.

http://www.nasa.gov/centers/glenn/technology/warp/ideachev.html
http://en.wikipedia.org/wiki/Breakthrough_Propulsion_Physics_Program#Differential_sail
http://www.daviddarling.info/encyclopedia/D/differential_sail.html

[Rodal]

...
 Mull's QV. If I wanna go thru the atmo w/o expelling propellant, I gotta use a propeller. Mull, yer gonna have to come up with a propeller.  And then we can all start calling it the aether.

No, that's not Mull's model, that's Sonny White's model:

*Sonny White: models the QV (per his own words) as water around a submarine.  White thinks of the EM Drive as a propeller that pushes on the quantum vacuum electron-positron pairs to propel it forward and in turn it leaves a wake behind the submarine.  Sonny White said at the Ames conference in August 2014 that his next step is to try to measure the wake left behind by the EM Drive on the quantum vacuum by using another EM Drive behind the propelling EM Drive to measure the wake.




*Mulletron, contrary to Sonny White thinks of the quantum vacuum as a medium with intrinsic momentum. 
Thus, he thinks of the quantum vacuum not as an inert aether that just sits there as a solid with extremely high modulus of elasticity (as Maxwell thought of the aether).  Mull thinks of the quantum vacuum as a medium with momentum.
Thus no propeller is needed. What is needed (as per Feigel using the magnetoelectric effect, or as per helical anisotropy of a polymer dielectric, etc.) is a means to act as a sail against the wind, to let the quantum vacuum push the spacecraft: to transfer the momentum of the quantum vacuum into the spacecraft.

Notice that with the wind at the back of the sail, the downwind "leeward" region is the region with leading edge separation and where turbulent reattachment occurs, sometimes followed by trailing edge separation. 

Thus, Sonny White's idea presents a possible way to falsify one of these models: is there a wake behind the EM Drive (White) or a separated turbulent region upstream of the EM drive ?




Capisce ?

[RotoSequence]

I really like the idea of testing for turbulence. I smell a potential snag, though. How do we know the turbulence, if it exists, isn't extremely short-lived and difficult, if not impossible, to test for?

[SteveKelsey]

Stupid question from the peanut gallery,...again. If we are looking at QVF are we not looking at Planck scale events? I thought that the virtual particle pairs were created and destroyed at the Planck scale. If so, yes the wake might be very short lived and very small. Just a question while I buy John some more peanuts in the intermission.

[Mulletron]

I don't know how you could directly see what was happening at such a small scale. Most sources say the QV is Lorentz-invariant. Once source argues it is covariant (below). We can't treat it as if it is a fluid or anything like that. Anybody know if Goldstone's theorem applies here?

http://link.springer.com/chapter/10.1007%2F3-540-53941-7_9

http://www.ovaltech.ca/pdfss/The_Challenge_to_Create_the_Space_Drive.pdf

[Mulletron]

Man this stuff is weird. I used to think I had the electron all figured out. Nope.

http://www.pbs.org/wgbh/nova/blogs/physics/2012/10/quantum-foam-virtual-particles-and-other-curiosities/

[Lampyridae]

Rodal: Thanx for the English summary comparison of Mull & White's take on their QV models.  It is  not clear to me what the phrase "medium with intrinsic momentum" means.  We all know that TV is called a medium because it is neither rare nor well done.  This sense of the term "medium" does not apply.

However, if the QV (which sounds more and more like an aether, if ya ask me) has "intrinsic momentum" which can be selectively manipulated, then it must have a direction.

If this analogy has any applicability, then along with turbulent wake, the aether QV must also feature "weather", "current", "tides", and what have you, all dependent on the anisotropic distribution of mass in the universe.

Since the QVF is "foam" in spacetime, then the currents and tides of it should be the local gravitational fields.

If there is anything that modifies the QVF's parameters, you're looking at some serious unexplored physics.

[Rodal]

I don't know how you could directly see what was happening at such a small scale. ...

Stupid question from the peanut gallery,...again. If we are looking at QVF are we not looking at Planck scale events? I thought that the virtual particle pairs were created and destroyed at the Planck scale. If so, yes the wake might be very short lived and very small. Just a question while I buy John some more peanuts in the intermission.

Don't confuse the scale of the "particles" with the scale of turbulence and eddies.  The scale of turbulence is much larger.  Also don't assume that turbulence is found by taking "a picture" of the motion of the "particles", instead what is measured in turbulence (of fluids, of superfluids, of plasma, of the solar wind, etc.)  is the time variation of field variables.  In this case, it would be the time variation of the magnetic field B, and the electric field E interacting with the EM Drive  Turbulence has to do with amplification of fluctuations.  We can tell about turbulence by examining the power spectral density and the autocorrelation of the field variables.  For example, by examining the power law scaling, as Mandelbrot for example showed time and time again in multiple examples.

See for example, the following (2012) paper on turbulence of the solar wind:

https://www.vsp.ucar.edu/Heliophysics/pdf/ChandranLWS_summer_school_turbulence_2012.pdf

I am on record as not being a sympathizer of the quantum vacuum explanations, particularly of Dr. White's plasma modeling of the quantum vacuum, but one must recognize that in his attempt to measure a wake (using another EM Drive) he is proceeding scientifically in another attempt to falsify his theory.

The proponents of the quantum vacuum producing propulsion of the EM Drive as a sail should also try to falsify their theory:  if they predict that virtual particles actually can interact with the real atoms of the EM Drive copper to transfer their momentum to the EM Drive copper, this interaction may leave a signature in the power spectrum power law scaling.

[Ron Stahl]

I'm loosing feet with what is going on here with ME vs EM. Regarding the former, I understand Ron states it is not incompatible with GR, so not with SR, so not with Lorentz invariance. But it can predict the result of a situation that GR cannot predict, namely situation of a ME thruster thrusting. This "hole" in GR was never noticed because such prediction for such situation never needed, kind of, so possible Machian "extension" (?) to GR forgotten. How could it be that a mundane device like a ME thruster could leave classic frameworks GR + QFT voiceless ?

I think the answer here is to note that as I said, GR does not address the issue fo the origin of inertia.  Eistein liked Mach's explantion here.  He was in fact the one who coined the name, and it helped him form GR, but GR is not contingent upon Mach's Principle, so you would not expect to see GR extended to include inertia manipulation.  It was actually Dennis Sciama back in the 50's who first started connecting GR with MP.  Woodward merely followed Sciama's lead when he stumbled upon the surprise in the derivations that showed there was a way to manipulate inertia present.  He talks about this in detail in his book.

As for the higher order anisotropies... this looks like a nice playground, full of hills and hollows. What a GR compatible Machian physics would have to say different from what would say GR : local inertias don't care ? Anyway, it claims to predict an effect that is astounding for most people working with GR under the form of a ME thruster thrusting. Can't the theory devise one other type of experiment that is at least as astounding and that could lend itself to more convincing reproducible results ? Call it an experiment in fundamental science (à la Michelson and Morley). Better credibility to the theory if it can expose itself to experimental falsifiability on other grounds that notoriously capricious propellentless drives. Are there such other falsifiable grounds?

Woodward makes the argument in his book, which I chided him about for failing at the kinds of detail I would have liked, but basically his argument is that the flatness we observe with WMAP data, does indeed require that Mach's Principle be correct.  He says the issue is settled since WMAP.  It's a complex issue and again, I think he should have gone slower though the argument and would perhaps make a wonderful academic paper in and of itself, but I don't know if he took the jibe seriously.  I think he was writing again last summer but I don't know the subject or contents.

"Loosing feet with" sounds like an idiom from outside the English speaking world.  Can I ask where you're from?

[Ron Stahl]

I expect that Machian inertia researchers should have already addressed this issue more in depth and up-to-date than what I have seen, as it is important to completely address anisotropy of inertia vis-a-vis experiments to validate their theory.  Therefore I hope that the backers of Machian inertia can uncover better and up-to-date references to properly address the excellent point brought up by Mulletron.

I think they may have addressed the issue, and I'm not convinced the flatness of the universe isn't the issue--that anisotropy is only pertinent if you don't have flatness.  There's an interesting paper here:

http://www.haverford.edu/physics/dcross/research/papers/oral.pdf

That calls itself incomplete (one presumes because this is pre-WMAP), but seems to be addressing the issue, though I don't have time to read it right now.  Just saying from the short glance across that I made, it starts out addressing anisotropy and concludes with arguing about flatness and WMAP.  I think anisotropy may only matter so far as it concerns the gradient of the field.  If the field is flat, one wonders in what sense any anisotropy could make a difference.  But I haven't read the paper.  I can however recommend look at Woodward's book in this regard.  I haven't got time to search for the particular reference but I may later today.  Mullet, if you have an e-version, I suggest look for any WMAP references in the index and you'll find the discussion I'm thinking of pretty quickly.

[Rodal]

I expect that Machian inertia researchers should have already addressed this issue more in depth and up-to-date than what I have seen, as it is important to completely address anisotropy of inertia vis-a-vis experiments to validate their theory.  Therefore I hope that the backers of Machian inertia can uncover better and up-to-date references to properly address the excellent point brought up by Mulletron.

I think they may have addressed the issue, and I'm not convinced the flatness of the universe isn't the issue--that anisotropy is only pertinent if you don't have flatness.  There's an interesting paper here:

http://www.haverford.edu/physics/dcross/research/papers/oral.pdf

That calls itself incomplete (one presumes because this is pre-WMAP), but seems to be addressing the issue, though I don't have time to read it right now.  Just saying from the short glance across that I made, it starts out addressing anisotropy and concludes with arguing about flatness and WMAP.  I think anisotropy may only matter so far as it concerns the gradient of the field.  If the field is flat, one wonders in what sense any anisotropy could make a difference.  But I haven't read the paper.  I can however recommend look at Woodward's book in this regard.  I haven't got time to search for the particular reference but I may later today.  Mullet, if you have an e-version, I suggest look for any WMAP references in the index and you'll find the discussion I'm thinking of pretty quickly.

1) That's the same reference which I quoted.  It states that

"It remains to compare expansion coe±cients between the inertial mass and matter anisotropy at great
distance through the WMAP data of the CMB. From this comparison, limits can be set on
higher coe±cients to see whether these multipoles are accessible to observation."

2) Concerning flatness vs. anisotropy see this other reference I quoted:

In this work it is shown that there are some spatially homogeneous
but anisotropic models (Kantowski-Sachs and Bianchi type-III), with a positive
cosmological constant, for which the inhomogeneities in the distribution of matter on
the surface of the last scattering produce anisotropies (in large angular scales # »> 10±)
that do not di®er from the ones produced in Friedmann-Lemaitre-Robertson-Walker
(FLRW) models, if the density parameters are finely tuned.

3) Besides the issue of anisotropy and attempts to falsify Woodward's Machian theory by a more classical experiment (rather than EM Drives, as remarked by frobnicat) another issue with Woodward's Machian theory has to do with the instantaneous inertial effect due to most distant masses (Woodward proposed that this be addressed through Wheeler-Feynman_absorber_theory).

If the Machian effect is most importantly due to the most distant masses, and those masses can only  be observed in the distant past (due to the time that it has taken for their photons to reach us), how is the Woodward Machian theory capable of falsification if what would matter would be the instantaneous state of anisotropy of those distant masses?  (that instantaneous state of anisotropy being unobservable because those distant masses can only be observed with the delay due to the speed of light and their very large distance) ?

[SteveKelsey]

I am not sure you can conflate the turbulence created in the soler wind with the proposed QVF wake can you? The solar wind is composed of elementary particles which are of quite a different scale from the Planck levels involved in virtual particle production. I understand conceptually where you are going but I don't understand how the scale of the fields are independent of the scale constraints that apply to virtual particle production. My obsession with scale has nothing to do with John's craving for Virginia scale peanuts, which are also virtual at this point.