Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 2166224 times)

Online Stormbringer

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I am not going to pretend like I have a real firm grip on the math or even the theory but...

The experiments in the articles I linked (and in other related articles I didn't) seem to me like the interaction of the fields in the em cavity might just accidentally create the condition needed for particle transition and possibly would create an imbalance in the system as particles appeared or disappeared from the mirror sector.

     The primary ( external ) requirement in one of the experiments was a very weak mirror magnetic field which would be provided naturally by the earth itself via trapped mirror matter particles mixed in the normal matter of the earth and collected by sweeping space (inelastic collisions and gravitational interaction) as solar and galactic orbital motions occur over geological and cosmic time scales.

EDIT:  On consideration this might not bode well for this to work in space unless a mirror magnetic source was deployed with the device. But that might be one way to test the hypothesis. Of course; you could just look for the loss or gain of particles in the cavity or near the cavity.

EDIT:  The sea of mirror particles would work just as well as quantum plasma i think. It Would perform the same function.
« Last Edit: 04/12/2015 07:51 PM by Stormbringer »
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Online Stormbringer

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I don't think running the experiment in air would have much effect on signal. As far as I know most interferometry experiments are in open air. The laser doesn't care much at short ranges.
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Offline aceshigh

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all these theories of the virtual particles having mass or not (I guess they have, otherwise wouldn´t be used for propulsion)... wouldn´t the total mass of virtual particles be much greater than the mass of even dark energy + dark matter together, and thus cause a collapse of the universe?

Online Stormbringer

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Well the mass of particles is a sum of the mass energy equivalence of all their properties which turns out to leave a slight overabundance of positive mass.

The negative bare mass is assumed in order to get rid of infinities and divergences (infinite electrical and gravitational self energy) and it is large; In some theories it is infinite; but that is theoretical.

 In practice the negative mass is manageable in the same way that the virtual particle world is supposed to be infinite but in practice is extremely low energy. Dr Woodward said something about this. In practical terms ZPE is tiny because generally only the very lowest energies are ever manifest from it. This is because though there are all possible mass energy equivalents it the vast probabilities cause only the lower powered virtual stuff to be "commonly" present. The lower energy possibilities swamp the larger ones. I hope I expressed that properly. if I didn't; it's my fault and not my sources.

On negative mass side of the equation defining particle mass there is a factor of C^4 while on the positive side on the right side of the equals sign there is the standard C^2 term. So even if the negative mass (assuming it can be made manifest) is limited it would still be quite large; easily a Jupiter mass worth. Perhaps Dr Woodward is being overly optimistic but his grasp of the math, theory and history of the evolution of the standard model is formidable. I would not bet against him. 
« Last Edit: 04/13/2015 03:22 AM by Stormbringer »
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Offline dustinthewind

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all these theories of the virtual particles having mass or not (I guess they have, otherwise wouldn´t be used for propulsion)... wouldn´t the total mass of virtual particles be much greater than the mass of even dark energy + dark matter together, and thus cause a collapse of the universe?

Interesting point.  If I remember correctly the vacuum is seething with waves of energy but statistically those waves interfere with each other destructively so that there appears to be nothing.  However there is still chance that energy at some points in the randomness will suddenly constructively interfere and become real.  Hope I'm not mistaken here. 

Maybe considering time slows near matter then with time passing by faster in space more particles pop into existence farther from the gravity source then near which might suggest a pressure but as stated earlier the Casimir force is supposed to drop off by 1/r^4 rather than 1/r^2 so ...  maybe there is some way to reconcile that and maybe not. 

While energy has its equivalence to mass and one might then suppose energy could induce gravity.  There is a way out of the gravity problem you mention.  Consider the universe to be infinite.  Gravity inside of a shell goes to zero if you go through the math and is why earth gravity drops to zero in the center of the earth.  (Also why the hollow earth ideas are wrong , eg. no gravity inside the hollow earth.) By the speed of light our universe we perceive I think is centered on us and so we are in the center of concentric shells of the quantum sea.  If this quantum sea is even density in general then gravity should cancel out. 
« Last Edit: 04/13/2015 03:09 AM by dustinthewind »

Offline zen-in

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A Poynting vector is not a field.   In your drawing the Poynting vector is dispersed in all directions because the energy flow is entirely due to thermal loss. (DC case)   If there are AC drives to the capacitor and gap magnet then some energy is transferred to near field RF radiation.   Nothing exotic happens here.  The em fields just combine.

I don't get your point.

1. CW's drawing does not show a Poynting vector dispersed in all directions, but a very directional vector going from the left to the right in the picture.

2. That Poynting vector S = ExB actually gives a Lorentz force F = q(E + vxB) when electric charges are able to flow within the electric field. If the sum of those electric charges in movement are able to create an electric current in a continuous charge distribution, i.e. with a current density J due to the charge density ρ, the Lorentz Force is then a "3D volumetric force", accelerating all electric charges in the same direction whatever their sign, and also the neutral atoms in the plasma with them, through collisions. This is the basis of magnetohydrodynamics applied to propulsion (MHD accelerators), sometimes called magnetoplasmadynamic (MPD) thrusters when the accelerating fluid is a ionized gas.


I think you might be mixing a lot of things together here and jumping to conclusions.   If you believe this gap magnet and capacitor can generate reactionless thrust you should build it and test it out for yourself.   I could give you 20-30 more interesting ideas I have played with in the last 15 years when you get done with that one.  Just because something looks "cool" doesn't mean it has any significance.

Offline aero

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Since you all have brought it up, I was thinking about that question earlier today so I did a web search. Turns out that there are 5 different theories that could potentially be used to estimate the energy mass of the QV. General Relativity and Quantum Theory are two that disagree by over 100 orders of magnitude. One of the theories can't be applied and the other two disagree wildly. The estimate that has some observational support comes from GR from which the answer is, Energy density, rho =  7x10-27 kg/m3.

The observational support comes from the expanding universe being caused by the pressure of the QV where rho = 3 P.
The 3 comes from the fact of 3 spacial dimensions. Then it gets complicated ...

As I recall, my search key was  - mass energy of quantum vacuum - .
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Offline MichaelBlackbourn

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I have to thank StarDrive and others. I hadn't heard of pilot waves and the idea of a return to a deterministic universe with the potential to leverage the 'medium' that the waves travel through is very interesting. The fact that Einstein preferred it and that all objections to it have been found lacking is outstanding. I also like how the measurement problem becomes just a Normal problem, not something intrinsic to the universe. Great reading.

The oil droplet experiments are excellent.

Best of luck finding a way to push against this 'sea'. I hope EMdrive or Woodward gives us something other than tossing atoms overboard for spaceflight.

Imagine if EMdrive is shown to be repeatable then there will be a change in the preferred QM interpretation.

Offline CW

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A Poynting vector is not a field.   In your drawing the Poynting vector is dispersed in all directions because the energy flow is entirely due to thermal loss. (DC case)   If there are AC drives to the capacitor and gap magnet then some energy is transferred to near field RF radiation.   Nothing exotic happens here.  The em fields just combine.

I don't get your point.

1. CW's drawing does not show a Poynting vector dispersed in all directions, but a very directional vector going from the left to the right in the picture.

2. That Poynting vector S = ExB actually gives a Lorentz force F = q(E + vxB) when electric charges are able to flow within the electric field. If the sum of those electric charges in movement are able to create an electric current in a continuous charge distribution, i.e. with a current density J due to the charge density ρ, the Lorentz Force is then a "3D volumetric force", accelerating all electric charges in the same direction whatever their sign, and also the neutral atoms in the plasma with them, through collisions. This is the basis of magnetohydrodynamics applied to propulsion (MHD accelerators), sometimes called magnetoplasmadynamic (MPD) thrusters when the accelerating fluid is a ionized gas.


I think you might be mixing a lot of things together here and jumping to conclusions.   If you believe this gap magnet and capacitor can generate reactionless thrust you should build it and test it out for yourself.   I could give you 20-30 more interesting ideas I have played with in the last 15 years when you get done with that one.  Just because something looks "cool" doesn't mean it has any significance.

Hmm.. I think you're somewhat misunderstanding my intention. First of all, I don't believe that this contraption does anything special. It is simply a practical model of how to most efficiently and simply create a volume of space that also contains unidirectional Poynting vectors. Unidirectional Poynting vectors seem to be the key to Dr. White's conjecture.. at least to me. Maybe I'm wrong on this. Also, Dr. White's conjecture is no reactionless drive, because he predicts an interaction with a 'virtual QV plasma' that can be used similarly as in 'real' MHD thrusters. Although I agree that apparent 'coolness' of something doesn't imply any kind of significance, this was really not the point.

Best regards
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Offline Star-Drive

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Folks:

From our Q-V plasma code studies, it is becoming clear that the Poynting power flow vector is only one of several parameters that has to be used in determining the magnitude and direction of the Q-V plasma flow and its resulting reaction thrust in the QVH/MHD based thrusters such as the EM-drives.  In fact the Cannae pillbox cavity produces thrust in the opposite direction than what the net Poynting vector would lead one to expect.  We think, though have not confirmed yet, that this is due to the hydrodynamics of the Q-V plasma and how it interacts with high ac E-field volumes that may be present in the operational thruster, such as the high ac E-fields developed in the small OD of the Cannae Teflon Z-matching tube located in its RF input section.  I'm re-appending a Rice University paper on the hydrodynamics of the vacuum for your reference and study.  You will find that a Q-V plasma acts quite a bit like a water based fluid, but with some startling differences as well, since it does salute MHD rules as well AND the still curious rules of the Quantum world.

Best, Paul M.

PS: From astrophysics it appears that the Quantum-Vacuum (Q-V) has an average density of 9.1x10^-27 kg/m^3 in the observable universe, but it can be much higher near electric charges such as the hydrogen proton.  In fact our new Eagleworks paper shows that the Q-V plasma density should increase at the 1/r^4 distance relationship demonstrated by the Casimir effect.  In fact due to this 1/r^4 scaling factor, as one approaches the classical radius of the proton, the Q-V density goes up to nuclear matter density.  To me that implies that ALL subatomic particles are just various types of vortices of Q-V...
« Last Edit: 04/13/2015 01:03 PM by Star-Drive »
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Online Stormbringer

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Offline Rodal

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...I'm re-appending a Rice University paper on the hydrodynamics of the vacuum for your reference and study.  You will find that a Q-V plasma acts quite a bit like a water based fluid, but with some startling differences as well, since it does salute MHD rules as well AND the still curious rules of the Quantum world.

Best, Paul M.

...
Hi Paul, looking at equation (4.22) in the attachment it appears that Stevenson's hydrodynamic model for the vacuum ignores electromagnetism and shear stresses: it has all components of Poynting's vector equal to zero and all shear stress components equal to zero.  The only non-zero component of Maxwell's stress tensor in Stevenson's formulation is pressure.  Thus, Stevenson models the vacuum as a fluid without any viscosity, incapable of supporting any shear stress, a superfluid.  He only considers the energy-density and the pressure as variables.

He doesn't appear (at least in the attached paper) to have developed his theory yet to consider any magnetohydrodynamics.  Also his theory is 3D+time standard relativity, without considering any extra space dimensions.

Does he have other papers where he deals with magnetohydrodynamics?







This paper discusses the electromagnetic (EM) field interacting with the quantum vacuum, where the vacuum is described as a superfluid:

http://arxiv.org/pdf/1204.6380v5.pdf

Interaction between the electromagnetic field and the quantum vacuum is shown to endow (charged) particles with internal structure and spatial extent.


« Last Edit: 04/14/2015 01:45 AM by Rodal »

Offline Mulletron

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Just wanted to share the good news! Put a check in the box for diametric drives.

http://www.nature.com/nphys/journal/v9/n12/full/nphys2777.html?WT.ec_id=NPHYS-201312
http://phys.org/news/2013-10-optical-diametric.html
http://www.creol.ucf.edu/Research/Publications/7155.pdf

Other stuff I saved to share:
http://revolution-green.com/optics-breakthrough-demonstrates-new-behaviors-physics/
http://www.researchgate.net/publication/262451086_Paritytime-symmetric_whispering-gallery_microcavities
http://arxiv.org/ftp/arxiv/papers/1308/1308.4564.pdf


Hold onto your hats for this one....see the double torus in figure 1. Using that example, linked to below, applied to the whispering gallery research above, can the internal dimensions of the Emdrive be topologically morphed into the double torus (linked by a fiber) configuration from above and still conserve the same properties? I can do the transformation in my head and it kinda makes sense, and taking the continuously changing diameter longitudinally, where is the "balanced gain and loss?"
http://www.mit.edu/~linglu/pdf/2014_Lu_NatPhoton.pdf

Other stuff that I read over and is applicable:
http://arxiv.org/abs/0707.4407 (about the Cr₂O₃)
http://arxiv.org/abs/0903.1261 "
http://www-dft.ts.infn.it/~resta/gtse/axion.pdf (slide 11), and axions


http://arxiv.org/abs/0710.2219 (net force zero from virtual EM, nontrivial from real EM)


Way far out stuff, still applicable:
http://arxiv.org/abs/1408.1636
http://arxiv.org/ftp/arxiv/papers/1009/1009.5663.pdf
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.10.1027&rep=rep1&type=pdf

Managing breakthrough research, nice insider view:
http://gcep.stanford.edu/pdfs/lh-ivzYPrcfEnjOxV0q59g/7_11_millis_breakthrough.pdf

PT symmetry and nonreciprocal dynamics of linear and angular optical momentum.
http://arxiv.org/ftp/arxiv/papers/1409/1409.7031.pdf

The ESA had a study called Ariadna 04/1201 and a contract called PHOTONIMPULS ANR-09-BLAN-0088-01 to investigate Feigel's claims, derive a Lorentz invariant (and correct) description of the Feigel process, and figure out if the QV can be used for propulsion:
http://www.esa.int/gsp/ACT/ariadna/projects/ari_study_04-1201.html
http://www.esa.int/gsp/ACT/doc/ARI/ARI%20Study%20Report/ACT-RPT-PHY-ARI-041201-Koln_Feigel.pdf
http://www.esa.int/gsp/ACT/doc/ARI/ARI%20Study%20Report/ACT-RPT-PHY-ARI-041201-Grenoble_Feigel.pdf










Challenge your preconceptions, or they will challenge you. - Velik

Offline dustinthewind

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http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.10.1027&rep=rep1&type=pdf


bottom of page 8 "The phase displacements are exactly those that are required to produce constructive interference in the region behind the EGM Array and destructive interference in the region ahead of the array. They..."

Thanks Mulletron. I recognize the concept but I didn't know about this paper.  I am sure it is directly related to the idea I had posted in the other thread http://forum.nasaspaceflight.com/index.php?topic=36911.0 .  I find it interesting in the paper it is suggested relating it to the zero point field and possibly gravity.  It is also mentioned negative energy density and the resulting radiation projected. 

I'll have to take a closer look at some of the others.

and the post here:
I still think we can violate newtons 3rd law in a way but in another way it is not violated because the propulsion device projects radiation out one end.  This looks like radiation propulsion but by sticking a dielectric between the two current loops we can change the speed of light making the two current loops closer or lowering the frequency needed while also getting near field effects?  What this does for the radiation projected I'm not exactly sure but I would assume it should intensify.  This is assuming none of the current loops have constant current but are both changing in time and out of phase pi/2 (see figure EM Propulsion 2.png). 

I guess the idea was if there was something similar going on inside the radiation cavity...

The graphic posted before that is associated with the concept in the paper.

Offline flux_capacitor

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Just wanted to share the good news! Put a check in the box for diametric drives.

http://www.nature.com/nphys/journal/v9/n12/full/nphys2777.html?WT.ec_id=NPHYS-201312
http://phys.org/news/2013-10-optical-diametric.html
http://www.creol.ucf.edu/Research/Publications/7155.pdf

About this diametric drive stuff:

Those researchers cite Marc G. Millis (1997) but don't even bother to cite physicist Joaquin Mazdak Luttinger who was first to imagine that strange behavior in 1951, nor Herman Bondi who gave it its official name in 1957 in the first peer-reviewed paper on the subject: the runaway motion. They even appear to don't know the designation by the way. I cite those pioneers only to show this is an old paradox known in GR for a long time, not a recent discovery.

Except that the "runaway effect" presupposes that the couple "positive mass + negative mass" would accelerate together indefinitely, which is an unphysical effect that ruled-out the possibility of the natural existence of negative mass in our universe. It presupposes that negative mass repels both other negative masses and positive masses.

Recent studies shows on the contrary that positive mass attracts positive mass, negative mass attracts negative mass, but positive mass and negative mass repel each other. See http://en.wikipedia.org/wiki/Negative mass#Runaway motion

In this context, no diametric drive.

Next, in the experiments you linked, how real massless photons in optical fibers can create an "antigravity effect" like a hypothetical negative mass is beyond me. I think their effect may be real but very, very different than the physical effect of a true effective negative mass matter, if we were able to produce some.



The ESA had a study called Ariadna 04/1201 and a contract called PHOTONIMPULS ANR-09-BLAN-0088-01 to investigate Feigel's claims, derive a Lorentz invariant (and correct) description of the Feigel process, and figure out if the QV can be used for propulsion:
http://www.esa.int/gsp/ACT/ariadna/projects/ari_study_04-1201.html
http://www.esa.int/gsp/ACT/doc/ARI/ARI%20Study%20Report/ACT-RPT-PHY-ARI-041201-Koln_Feigel.pdf
http://www.esa.int/gsp/ACT/doc/ARI/ARI%20Study%20Report/ACT-RPT-PHY-ARI-041201-Grenoble_Feigel.pdf

About the ARIADNA study #04/1201 from the ESA, evaluating the anomalous Feigel Process for the extraction of momentum from a vacuum, I quote the conclusions of the final report (emphasis by me):
Quote
On the basis of our study, we come to the following conclusions: The derivation of the generally covariant relativistic constitutive relations for a moving magnetoelectric medium, together with the subsequent analysis of the vacuum waves travelling through the sample of a finite size shows that the magnetoelectric body will not move, despite the presence of a certain asummetry between the left- and right-moving waves in the matter. However, this only refers to the case of waves due to vacuum fluctuation.
For the real waves falling symmetrically from the two sides on a magnetoelectric body, we expect a nontrivial effect of the Feigel type. Thus, we cannot confirm the possibility of "extracting momentum from nothing".

So this study pretty much invalidated the anomalous Feigel effect when considering the QFV conjecture, aka "extraction of momentum from the virtual photons of the quantum vacuum fluctuations". It showed however that an anomalous Feigel effect could be obtained with real photons. So for a thruster, does the photons (microwaves ?) generator (magnetron ?) has to be decoupled (exterior) from the thruster or could it be part of it as in an EmDrive?

Offline Rodal

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Paul March has nicely summarized funding and future of the EM Drive project at NASA, a few hours ago in the Advanced Propulsion thread of LinkedIn, as follows:

Quote
"It is a prediction, but experimental results are needed. VASIMR drive finally got those funds at NASA, I would like to see something similar on EM-Drive"

So would we, but don't hold your breath. In the meantime we have enough funding for the rest of the NASA fiscal year to keep building up our 0.12-to-1.2kW, WR-340 waveguide based EM-Drive magnetron system on a teeter-totter balance system using a earlier aluminum frustum as our test article. The build of that experiment should be completed by the end of June using just civil servant labor and the existing hardware on hand. Then we get to see if Shawyer's and the Chinese's reported EM-Drive results are the real deal, or not.

Offline Notsosureofit

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@ Mulletron
Great find!

Separating the two photon directions allows them to control their interaction (equivalent of the cavity taper and/or dielectric).  In the EMdrive the two directions are intimately coupled within the cavity.  If you fold figure 1 in half (vertical fold line) you have something like a tapered microwave cavity.   I don't see the need to invoke negative mass (they did say effectively) as the same description looks like the "self accelerating" particle papers.

The question is "is the nonlinearity a required condition ?".

Offline Star One

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Paul March has nicely summarized funding and future of the EM Drive project at NASA, a few hours ago in the Advanced Propulsion thread of LinkedIn, as follows:

Quote
"It is a prediction, but experimental results are needed. VASIMR drive finally got those funds at NASA, I would like to see something similar on EM-Drive"

So would we, but don't hold your breath. In the meantime we have enough funding for the rest of the NASA fiscal year to keep building up our 0.12-to-1.2kW, WR-340 waveguide based EM-Drive magnetron system on a teeter-totter balance system using a earlier aluminum frustum as our test article. The build of that experiment should be completed by the end of June using just civil servant labor and the existing hardware on hand. Then we get to see if Shawyer's and the Chinese's reported EM-Drive results are the real deal, or not.

Thanks for that. But you know what they say   extraordinary claims require extraordinary evidence. I'm sure if this is ever proven too a sufficient degree they'll have no problem obtaining funding.

Offline Rodal

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@ Mulletron
Great find!

Separating the two photon directions allows them to control their interaction (equivalent of the cavity taper and/or dielectric).  In the EMdrive the two directions are intimately coupled within the cavity.  If you fold figure 1 in half (vertical fold line) you have something like a tapered microwave cavity.   I don't see the need to invoke negative mass (they did say effectively) as the same description looks like the "self accelerating" particle papers.

The question is "is the nonlinearity a required condition ?".

They (http://www.creol.ucf.edu/Research/Publications/7155.pdf) invoke the Kerr effect.  For the EM Drive, it would be the AC Kerr effect ( http://en.wikipedia.org/wiki/Kerr_effect#AC_Kerr_effect ) resulting in self-focusing.  The dielectric material would need to have a significant second-order nonlinear refractive index.  Does HDPE have a significant second-order nonlinear refractive index ?

Without a dielectric anisotropic insert in the EM Drive, it appears that there would be no nonlinearity, and therefore there would be no measurable "thrust" due to self-focusing due to this nonlinear effect. 

In the truncated cone EM Drive without a dielectric anisotropic polymer one would still have the "focusing" due to the geometry, but isn't this (conical geometry focusing effect) a linear effect and therefore self-cancelling for linear harmonic standing waves in the closed cavity?

Assuming that the vacuum itself has a negligible second-order nonlinear refractive index, it will be interesting to see whether Eagleworks reproduces Shawyer's and the Chinese's experiments without a polymer dielectric insert.
« Last Edit: 04/14/2015 03:39 PM by Rodal »

Offline Notsosureofit

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There are still the various thin film coatings (oxides, etc.) that naturally form on the inside of the cavity walls.

Added:  If nothing else, it looks like the force (acceleration) is in the right direction (toward the small end).

If I'm reading correctly, they did not (?) observe defocusing, and they would still get an effect if the negative mass was zero. (?)
« Last Edit: 04/14/2015 04:19 PM by Notsosureofit »

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