Author Topic: EM Drive Developments - related to space flight applications - Thread 10  (Read 197999 times)

Offline Chrochne

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What you say is quite true to what people in news industry told me. The reporters that spoke directly to the Shawyer can not tell / share everything he told them. I wrote about this here on NSF too. Any interview with the Shawyer needs to go trough the check with the military guys before it is released. Usually around 30% to 50% is changed.
...
I guess I am one of very few here who does not find it strange that they (military) want to keep it under wraps for now. They done it with some famous techs in the past. Like that B-2 stealth bomber or more recently X-37B (I do not think they are testing EmDrive there yet).
This isn't how it would work if what you are describing was real. Military wouldn't let someone (Shawyer) go say what they want to the media, and then the media report is filtered afterward. They would restrict what is said in the first place, and if it is serious enough, the only releases of any information to people in the media would be pre-screened before the media sees them.

Claims like the one you just made that don't fit with what would actually be the case if the military were involved increase the reasons people doubt any claim that the military is involved.

I would thought in these cases the person in question would either be given a prepared script or not allowed to speak at all & just a press release put out.
Yes,  as I said that would be a typical situation, Chrochne describing something completely different is plenty of evidence that what he described never actually happened.

Giving Chrochne the benefit of the doubt that he is not making stuff up, one possibility is that Shawyer reviewed and revised the news story before release. The military involvement could then either be a lie Shawyer told the media, or a misunderstanding or miscommunication that that happened further down the line.

You may check what I wrote. Or is it too difficult for you to do that? It is much more easier to say I lie. 😀

Offline meberbs

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What you say is quite true to what people in news industry told me. The reporters that spoke directly to the Shawyer can not tell / share everything he told them. I wrote about this here on NSF too. Any interview with the Shawyer needs to go trough the check with the military guys before it is released. Usually around 30% to 50% is changed.
...
I guess I am one of very few here who does not find it strange that they (military) want to keep it under wraps for now. They done it with some famous techs in the past. Like that B-2 stealth bomber or more recently X-37B (I do not think they are testing EmDrive there yet).
This isn't how it would work if what you are describing was real. Military wouldn't let someone (Shawyer) go say what they want to the media, and then the media report is filtered afterward. They would restrict what is said in the first place, and if it is serious enough, the only releases of any information to people in the media would be pre-screened before the media sees them.

Claims like the one you just made that don't fit with what would actually be the case if the military were involved increase the reasons people doubt any claim that the military is involved.

I would thought in these cases the person in question would either be given a prepared script or not allowed to speak at all & just a press release put out.
Yes,  as I said that would be a typical situation, Chrochne describing something completely different is plenty of evidence that what he described never actually happened.

Giving Chrochne the benefit of the doubt that he is not making stuff up, one possibility is that Shawyer reviewed and revised the news story before release. The military involvement could then either be a lie Shawyer told the media, or a misunderstanding or miscommunication that that happened further down the line.

You may check what I wrote. Or is it too difficult for you to do that? It is much more easier to say I lie. 😀
I quite explicitly gave you the benefit of the doubt. Maybe you need to re-read my post.

Online Req

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What you say is quite true to what people in news industry told me. The reporters that spoke directly to the Shawyer can not tell / share everything he told them. I wrote about this here on NSF too. Any interview with the Shawyer needs to go trough the check with the military guys before it is released. Usually around 30% to 50% is changed.
...
I guess I am one of very few here who does not find it strange that they (military) want to keep it under wraps for now. They done it with some famous techs in the past. Like that B-2 stealth bomber or more recently X-37B (I do not think they are testing EmDrive there yet).
This isn't how it would work if what you are describing was real. Military wouldn't let someone (Shawyer) go say what they want to the media, and then the media report is filtered afterward. They would restrict what is said in the first place, and if it is serious enough, the only releases of any information to people in the media would be pre-screened before the media sees them.

Claims like the one you just made that don't fit with what would actually be the case if the military were involved increase the reasons people doubt any claim that the military is involved.

I would thought in these cases the person in question would either be given a prepared script or not allowed to speak at all & just a press release put out.
Yes,  as I said that would be a typical situation, Chrochne describing something completely different is plenty of evidence that what he described never actually happened.

Giving Chrochne the benefit of the doubt that he is not making stuff up, one possibility is that Shawyer reviewed and revised the news story before release. The military involvement could then either be a lie Shawyer told the media, or a misunderstanding or miscommunication that that happened further down the line.

You may check what I wrote. Or is it too difficult for you to do that? It is much more easier to say I lie. 😀
I quite explicitly gave you the benefit of the doubt. Maybe you need to re-read my post.
Speaking of expected/constructive dialogue, citations or first-hand information are what you would expect as a response from a credible interlocutor here, not a trite and adversarial/defensive "go look it up."

Offline Chrochne

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What you say is quite true to what people in news industry told me. The reporters that spoke directly to the Shawyer can not tell / share everything he told them. I wrote about this here on NSF too. Any interview with the Shawyer needs to go trough the check with the military guys before it is released. Usually around 30% to 50% is changed.
...
I guess I am one of very few here who does not find it strange that they (military) want to keep it under wraps for now. They done it with some famous techs in the past. Like that B-2 stealth bomber or more recently X-37B (I do not think they are testing EmDrive there yet).
This isn't how it would work if what you are describing was real. Military wouldn't let someone (Shawyer) go say what they want to the media, and then the media report is filtered afterward. They would restrict what is said in the first place, and if it is serious enough, the only releases of any information to people in the media would be pre-screened before the media sees them.

Claims like the one you just made that don't fit with what would actually be the case if the military were involved increase the reasons people doubt any claim that the military is involved.

I would thought in these cases the person in question would either be given a prepared script or not allowed to speak at all & just a press release put out.
Yes,  as I said that would be a typical situation, Chrochne describing something completely different is plenty of evidence that what he described never actually happened.

Giving Chrochne the benefit of the doubt that he is not making stuff up, one possibility is that Shawyer reviewed and revised the news story before release. The military involvement could then either be a lie Shawyer told the media, or a misunderstanding or miscommunication that that happened further down the line.

You may check what I wrote. Or is it too difficult for you to do that? It is much more easier to say I lie. 😀
I quite explicitly gave you the benefit of the doubt. Maybe you need to re-read my post.

I sent you personal message so we can work it out there. I do not want to get on the nerves of the kind moderators here.

Online Mulletron

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I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.
Challenge your preconceptions, or they will challenge you. - Velik

Offline Nerm999

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@Monomorphic did you ever get any more than a couple of disparate runs from you previous frustrum and power setup? Eg multiple runs in all the different orientations and different power levels. I was looking forward to some more comprehensive results, that one could draw some conclusions from, but they haven't seen the light of day? Hoping that this new frustum can provide them.

I have two main goals to accomplish before I do a methodical series of test runs as described: spherical end-plates and an increase from 2W to 20W. Roger Shawyer emailed me about my initial results a few months ago and encouraged that I go with spherical end-plates to increase the thrust. The 2W amp and pre-amp is very inefficient. It takes 7A to get that 2W while the new amp will output 30W at 10A. 

I have a hard deadline of November 1 as I will be presenting most the data then. So expect a flurry of work between now and then, with October being VERY busy.

Awesome, thanks, can't wait for the results!

Offline Bob Woods

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I sent you personal message so we can work it out there. I do not want to get on the nerves of the kind moderators here.
Good idea. Here's what Chris Bergin did to a guy last week.... ;)

« Last Edit: 08/12/2017 08:27 AM by Bob Woods »

Offline Flyby

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He'd better hire a designer for his PAV too. Why not just put the tanks (as well as three couples of EmDrives) at the vertices of an equilateral triangle:


Then you just have to modulate the power applied at each vertex to pitch and roll, thus accelerate and move forward, turn, slow down and stand still of even move backward, like a helicopter. But a totally silent one with no rotating airfoil!

*Sigh* This is still just plain science fiction.

Been pondering a bit about the design (as you suggested  ;D ), especially about the layout of the "engines".
I think there will be both a stability and safety issue with Shawyer's  current design.

Let me elaborate :
There is no real advantage to be gained from having 3 or 4 arms. 3 points are need to obtain a minimum stability ( if you keep the center of mass in the middle).
However, you then have zero backup or safety margin. one engine goes down and your vehicle spins out of control. Also, the slightest variation in one of the engines will cause an imbalance.

An extra 4rth arm gives you a needed engine redundancy, but not the extra stability, because the CoM lays at the edge of the "remaining working engine" triangle. Resulting in a highly unstable situation for the vehicle.
Both 3 or 4 arm solution will turn out to be uncontrollable in real weather conditions, if the engine(s) on one arm fail, so...

I'd suggest a hex or octo arm configuration, so that if 1 engine fails the remaining engines will have no problem keeping the stability of the vehicle.



It is not for nothing that professional camera drones are almost all octo-arm based : they provide superior stability and reliability..

but all this starts on the premise that we have a working EMdrive... which we have yet to see confirmed...
« Last Edit: 08/12/2017 10:22 AM by Flyby »

Offline LowerAtmosphere

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I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.

A good start would be mentioning the gravitational potential U and talking about the topology of spacetime throughout the cavity.

Another old abandoned train of thought was the generation of negative energy fields in the upper cavity (or even throughout the wall). With this in mind, anti-Gravity only makes sense in the context of a warp bubble or gradient. Personally, I believe gravity alone is too weak to accelerate the cavity to Shawyer-levels, unless it is both counteracting the gravitational potential of our planet and sun and providing a minor accelerative force. Where the gravity discussion has gotten more exotic in the past years is applying QV energy density minimums to the EMDrive with reference to Dr. White. My early theories involved time-based relaxation and stickiness of the QV. Like a stirring pot the QV near the moving field modal peaks and the eddies would remain excited and additionally have areas where there is destructive interference and negative or flat values. The memory of the QV allows for using solitonized waves for QVP excitation which complements the B field in TE designs but nullifies or weakens the central focal point E field. Though it is unclear where this system would develop, pulsing it should allow for a decaying set of gravity  (depends on whether it is a multipolar resonant mode) gradients which solves CoE issues by relying on the QV to provide the energy which maintains such a temporary gravitational gradient. The resulting gradient and related crossover between "anti-gravity" and QV theories has been discussed in earlier threads. I am curious to see new opinions and more views on the ideal topology inside the cavity if assuming gravitational gradients are what cause or enable thrust.

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=41732.0;attach=1402267

Offline flux_capacitor

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I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.

A good start would be mentioning the gravitational potential U and talking about the topology of spacetime throughout the cavity.

Another old abandoned train of thought was the generation of negative energy fields in the upper cavity (or even throughout the wall). With this in mind, anti-Gravity only makes sense in the context of a warp bubble or gradient. {snip}

@Mulletron & LowerAtmosphere: Are you talking about something along the lines of Minotti's model? Not the scalar-tensor theory itself, but the consequence of any similar theory upon the gravitational potential within and around the vicinity of the cavity, as I presented in two former posts here and there (EmDrive NSF Thread #9, January 2017).

Online Rodal

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I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.

A good start would be mentioning the gravitational potential U and talking about the topology of spacetime throughout the cavity.

Another old abandoned train of thought was the generation of negative energy fields in the upper cavity (or even throughout the wall). With this in mind, anti-Gravity only makes sense in the context of a warp bubble or gradient. {snip}

@Mulletron & LowerAtmosphere: Are you talking about something along the lines of Minotti's model? Not the scalar-tensor theory itself, but the consequence of any similar theory upon the gravitational potential within and around the vicinity of the cavity, as I presented in two former posts here and there (EmDrive NSF Thread #9, January 2017).

A back of the envelope numerical calculation shows the practical difficulty of warping spacetime with the energy present in the EM Drive.  Spacetime is just too stiff for such puny energy. See:

https://blogs.scientificamerican.com/life-unbounded/just-how-resilient-is-spacetime/

and



<< it takes a HUGE amount of stress on space-time to produce an appreciable amount of warp or curvature ('G'). In fact it takes objects like the Earth (all 6 trillion trillion kilograms of it) to warp space-time to a level that we're intimately familiar with.>>
« Last Edit: 08/12/2017 03:50 PM by Rodal »

Offline SeeShells

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I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.

A good start would be mentioning the gravitational potential U and talking about the topology of spacetime throughout the cavity.

Another old abandoned train of thought was the generation of negative energy fields in the upper cavity (or even throughout the wall). With this in mind, anti-Gravity only makes sense in the context of a warp bubble or gradient. {snip}

@Mulletron & LowerAtmosphere: Are you talking about something along the lines of Minotti's model? Not the scalar-tensor theory itself, but the consequence of any similar theory upon the gravitational potential within and around the vicinity of the cavity, as I presented in two former posts here and there (EmDrive NSF Thread #9, January 2017).

A back of the envelope numerical calculation shows the practical difficulty of warping spacetime with the energy present in the EM Drive.  Spacetime is just too stiff for such puny energy. See:

https://blogs.scientificamerican.com/life-unbounded/just-how-resilient-is-spacetime/

and



<< it takes a HUGE amount of stress on space-time to produce an appreciable amount of warp or curvature ('G'). In fact it takes objects like the Earth (all 6 trillion trillion kilograms of it) to warp space-time to a level that we're intimately familiar with.>>
Or in a clearer way...

Offline flux_capacitor

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I didn't notice I gave a wrong link in a previous post (due to a typo in the use of brackets for URL tags). Below, the correct link to Lobo & Visser's 2004 paper.   

My conclusion about an effective negative energy source due to the coupling scalar field for engineering an Alcubierre metric with a low velocity warp drive comes from Visser after cross-reading several papers, one from Minotti then two (three actually) from Visser, links below. First, it was Minotti who triggered my interest in:

Minotti, F. O. (July 2013). "Scalar-tensor theories and asymmetric resonant cavities". Gravitation and Cosmology. 19 (3): 201–208. arXiv:1302.5690. doi:10.1134/S0202289313030080.

where he wrote in the introduction:
Quote from: Fernando Minotti
It appears that General Relativity might allow for such kind of reactionless propulsion, as exemplified and noted for the first time in [3], where the low velocity limit of some warp drive spacetimes was analyzed. As indicated there, negative energy densities are required to accomplish that and, notably, some scalar fields present this possibility.[4]


REFERENCES
[3] Lobo, F.S.N.; Visser, M. (25 November 2004). "Fundamental limitations on 'warp drive' spacetimes". Classical and Quantum Gravity. 21 (24): 5871. arXiv:gr-qc/0406083. doi:10.1088/0264-9381/21/24/011.

[4] Barceló, C.; Visser, M. (21 September 2000). "Scalar fields, energy conditions, and traversable wormholes". Classical and Quantum Gravity. 17 (18): 3843-3864. arXiv:gr-qc/0003025. doi:10.1088/0264-9381/17/18/318.


So it appears that Visser (working with Barceló and Lobo):
1) analyzed the possibility of low-velocity (v ≪ c) reactionless warp drives.
2) indicated negative energy was involved, although in lower quantity than for a relativistic warp drive, but still required.
3) told that some scalar fields would present this feature.

I source these three points in direct quotes below in Lobo & Visser's 2004 paper:

Quote from: Francisco S. N. Lobo and Matt Visser
Since we take the warp-bubble velocity to be non-relativistic, v ≪ c, we are not primarily interested in the "superluminal" features of the warp drive. Instead we focus on a secondary feature of the warp drive that has not previously been remarked upon — the warp drive (if it could be built) would be an example of a "reaction-less drive"
[…]
Additionally, certain classical systems (such as non-minimally coupled scalar fields) have been found that violate the null and the weak energy conditions [16, 17].
[…]
[equation (16)] is manifestly negative, and so the NEC [null energy condition] is violated for all v.


REFERENCES
[16] Barceló, C.; Visser, M. (21 September 2000). "Scalar fields, energy conditions, and traversable wormholes". Classical and Quantum Gravity. 17 (18): 3843-3864. arXiv:gr-qc/0003025. doi:10.1088/0264-9381/17/18/318.

[17] C. Barceló, C.; Visser, M. (1999). "Traversable wormholes from massless conformally coupled scalar fields". Physics Letters B.466: 127. arXiv:gr-qc/9908029. doi:10.1016/S0370-2693(99)01117-X.


In Barceló & Visser's 2000 paper, various theories using scalar fields and violating the NEC are listed, including the Brans–Dicke theory in refs [10, 11] of that paper. In their previous 1999 paper, even more Brans–Dicke links: refs [17, 18, 19, 20]. You can read them, but I'll stop expanding there otherwise it will become an endless citation story and the more papers are cited, the more the subject of warp drive becomes diluted. But there are obvious bridges linking all these works.

Online Rodal

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In Barceló & Visser's 2000 paper, various theories using scalar fields and violating the NEC are listed, including the Brans–Dicke theory in refs [10, 11] of that paper. In their previous 1999 paper, even more Brans–Dicke links: refs [17, 18, 19, 20]. You can read them, but I'll stop expanding there otherwise it will become an endless citation story and the more papers are cited, the more the subject of warp drive becomes diluted. But there are obvious bridges linking all these works.
Did you mean to type WEC instead NEC? (Weak Energy Condition). 

Possible violation of the weak energy condition is not a unique characteristic of scalar-tensor theories.  Einstein's theory admits solutions with properties that most physicists regard as unphysical, including violation of the weak energy condition.  The weak energy condition was postulated on purpose, precisely because gravitational theories admit such solutions.  Similarly other conditions are postulated to prevent other violations, like Hawking's condition to prevent time travel to the past.

Einstein's theory,for example (as shown by Goedel) even admits a solution where there are closed time loops.

The fact that all these gravitational theories admit such solutions does not mean that they are possible, and even if they were possible in theory, that they may be feasible in practice.  And most of all, that these solutions would be possible with the really tiny energy in the EM Drive.  Remember that E=Mc2, therefore the equivalent mass of the electromagnetic energy in the EM Drive, M=E/c2 is really tiny.

Scalar-tensor theories with parameters set in agreement with Cosmological measurements show a spacetime that is way too stiff to allow the EM Drive's energy to significantly warp spacetime.  The type of scalar-tensor theory used by Minotti is a modification of a theory that is not uniformly accepted by mainstream scientists.  The theory was shown by Minotti himself to be defective in that it showed anomalous incompatible coupling with the Earth's magnetic field.  Other scientists wrote of other defects of the theory, and to my knowledge has not been accepted.

Minotti had to modify the theory to eliminate this incompatibility with the Earth's magnetic field and gravitational measurements.  It remains now for Minotti to show that his theory is compatible with all cosmological measurements.  For example, what does Minotti's modified scalar-tensor theory show for a Magnetar?

« Last Edit: 08/13/2017 03:15 AM by Rodal »

Offline flux_capacitor

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In Barceló & Visser's 2000 paper, various theories using scalar fields and violating the NEC are listed, including the Brans–Dicke theory in refs [10, 11] of that paper. In their previous 1999 paper, even more Brans–Dicke links: refs [17, 18, 19, 20]. You can read them, but I'll stop expanding there otherwise it will become an endless citation story and the more papers are cited, the more the subject of warp drive becomes diluted. But there are obvious bridges linking all these works.
Did you mean to type WEC instead NEC? (Weak Energy Condition). 

Possible violation of the weak energy condition is not a unique characteristic of scalar-tensor theories.  Einstein's theory admits solutions with properties that most physicists regard as unphysical, including violation of the weak energy condition.  The weak energy condition was postulated on purpose, precisely because gravitational theories admit such solutions.  Similarly other conditions are postulated to prevent other violations, like Hawking's condition to prevent time travel to the past.

Einstein's theory,for example (as shown by Goedel) even admits a solution where there are closed time loops.

The fact that all these gravitational theories admit such solutions does not mean that they are possible, and even if they were possible in theory, that they may be feasible in practice.  And most of all that they would be possible with the really tiny energy in the EM Drive.  Remember that E=Mc2, therefore the equivalent mass of the electromagnetic energy in the EM Drive, M=E/c2 is really tiny.

Scalar-tensor theories with parameters set in agreement with Cosmological measurements show a spacetime that is way too stiff to allow the EM Drive's energy to significantly warp spacetime.  The type of scalar-tensor theory used by Minotti is a modification of a theory that is not uniformly accepted by mainstream scientists.  The theory was shown by Minotti himself to be defective in that it showed anomalous incompatible coupling with the Earth's magnetic field.  Other scientists wrote of other defects of the theory, and to my knowledge has not been accepted.

Minotti had to modify the theory to eliminate this incompatibility with the Earth's magnetic field and gravitational measurements.  It remains now for Minotti to show that his theory is compatible with all cosmological measurements.  For example, what does Minotti's modified scalar-tensor theory show for a Magnetar?

NEC. I'd better quote directly the passage from Barceló and Visser in their 2000 paper:

Quote from: Carlos Barceló and Matt Visser
There exist other classical systems that exhibit NEC violations, such as Brans–Dicke theory [17, 18, 19, 20], higher derivative gravity [21] or Gauss–Bonnet theory [22], but they are all based on modifications of general relativity at high energies. It is the simplicity of the scalar field theory that particularly attracted our attention.


[17] A. Agnese, M. La Camera (1995). "Wormholes in the Brans-Dicke theory of gravitation". Phys. Rev. D 51 (4): 2011. doi:10.1103/PhysRevD.51.2011.
[18] K.K. Nandi, A. Islam, J. Evans (1997). "Brans wormholes". Phys. Rev. D 55: 2497. arXiv:0906.0436.
[19] L.A. Anchordoqui, S. Perez Bergliaffa, D.F. Torres (1997). "Brans-Dicke wormholes in nonvacuum spacetime" Phys. Rev. D 55 (8): 5226. arXiv:gr-qc/9610070.
[20] M. Visser, D. Hochberg (1997). "Generic wormhole throats" in: The Internal Structure of Black Holes and Spacetime Singularities. Institute of Physics Press, Bristol). arXiv:gr-qc/9710001.
[21] D. Hochberg (1990). "Lorentzian wormholes in higher order gravity theories". Phys. Lett. B 251: 349. doi:10.1016/0370-2693(90)90718-L.
[22] B. Bhawal and S. Kar (1992). "Lorentzian wormholes in Einstein-Gauss-Bonnet theory" Phys. Rev. D 46 (6): 2464. doi:10.1103/PhysRevD.46.2464.

For what you said about scalar-tensor theories in general and Minotti's work about Lachičze-Rey & Mbelek's theory in particular: I know. But thanks to point this out for the audience.
« Last Edit: 08/12/2017 06:12 PM by flux_capacitor »

Online Rodal

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NEC. I'd better quote directly the passage from Barceló and Visser in their 2000 paper:

...
In general, violation of the null energy condition (the weakest of the energy conditions) leads to the breakdown of causality in general relativity and the violation of the second law of thermodynamics( https://arxiv.org/abs/0704.1814 ) . That is a severe pathology ! (To accept that the tiny energy going into the EM Drive could be breaking down causality and the 2nd law of thermodynamics).  To break down the NEC you first have to violate all the other energy conditions.





EM Drive violating the NEC means contemplating the EM Drive now as a time machine



That's too much (to me at least) to contemplate ;)  (although we have not heard back from some early EM Drive experimenters for quite a while  ??? )
« Last Edit: 08/12/2017 07:25 PM by Rodal »

Offline demofsky

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And most of all that they would be possible with the really tiny energy in the EM Drive.  Remember that E=Mc2, therefore the equivalent mass of the electromagnetic energy in the EM Drive, M=E/c2 is really tiny.
....
Thanks for this!  This really crystallized something for me. 

Going back to first principles, even allowing for some order of magnitude increases due to Compton scattering, etc. there is no way you can get anywhere near newton levels of thrust just by the energy introduced into the fustrum.

Therefore, if there is anything to this, thrust must be a second order effect of something caused by the asymmetry intruduced by the fustrum.  (And sincere apologies if this has been obvious to everyone except me!)

Online Rodal

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And most of all that they would be possible with the really tiny energy in the EM Drive.  Remember that E=Mc2, therefore the equivalent mass of the electromagnetic energy in the EM Drive, M=E/c2 is really tiny.
....
Thanks for this!  This really crystallized something for me. 

Going back to first principles, even allowing for some order of magnitude increases due to Compton scattering, etc. there is no way you can get anywhere near newton levels of thrust just by the energy introduced into the fustrum.

Therefore, if there is anything to this, thrust must be a second order effect of something caused by the asymmetry intruduced by the fustrum.  (And sincere apologies if this has been obvious to everyone except me!)

A fan with only  8.95 Watts input power can produce 204 milliNewtons (0.204 Newtons) of force


https://www.wired.com/2012/09/modeling-the-force-from-a-fan/

this is due to the force from air convection



204 milliNewtons/0.00895 kW = 22,793 mN/kW

for comparison Shawyer claimed 100 times less: up to 243 mN/kW for the Demonstrator,  this is the reason why it is conceivable that convection forces may play a role in the claimed results, and why it is important to run the experiments in a vacuum chamber (like NASA and TU Dresden) to eliminate thermal convection effects.  You also have Lorentz forces and thermal expansion forces (shift of center of mass in the pendulum setup) still present in a vacuum.
« Last Edit: 08/13/2017 03:33 PM by Rodal »

Offline moreno7798

I've been studying this silly copper can for years now and I think it's honest to God anti gravity. Gravitational induction. Everything else doesn't fit. I need help converting from my intuitive mind to something people can understand.

A good start would be mentioning the gravitational potential U and talking about the topology of spacetime throughout the cavity.

Another old abandoned train of thought was the generation of negative energy fields in the upper cavity (or even throughout the wall). With this in mind, anti-Gravity only makes sense in the context of a warp bubble or gradient. {snip}

@Mulletron & LowerAtmosphere: Are you talking about something along the lines of Minotti's model? Not the scalar-tensor theory itself, but the consequence of any similar theory upon the gravitational potential within and around the vicinity of the cavity, as I presented in two former posts here and there (EmDrive NSF Thread #9, January 2017).

A back of the envelope numerical calculation shows the practical difficulty of warping spacetime with the energy present in the EM Drive.  Spacetime is just too stiff for such puny energy. See:

https://blogs.scientificamerican.com/life-unbounded/just-how-resilient-is-spacetime/

and



<< it takes a HUGE amount of stress on space-time to produce an appreciable amount of warp or curvature ('G'). In fact it takes objects like the Earth (all 6 trillion trillion kilograms of it) to warp space-time to a level that we're intimately familiar with.>>
Or in a clearer way...


...and a possible way to do it.


Online Mulletron

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What I'm envisioning is the superposition of two counterpropagating, non-identical (in this case amplitude but in another model you can create beats using two different frequencies...like with a red and green laser in a common medium....but the guys using magnetrons are putting wide band noise into their cavities of multiple frequencies too) electromagnetic waves, the result is a partial standing wave. The partial standing wave is what's important. If I understand things correctly, of course one photon is massless, but a system of two nonparallel photons has a real mass. I envision that this partial standing wave is in fact massive, and it's the jerking motion of this massive wave that is responsible for gravitational induction (AC gravity...changing gravity...changing acceleration) and these disturbances in the gravitational field are propagating away, carrying away energy and momentum from the cavity (maximum theoretical Q? Instead of trying to directly measure gravitational radiation which is extremely difficult right now, maybe find the missing Q instead) asymmetrically (because of the octupole shape of the cavity). It isn't good enough to just accelerate a mass and achieve gravitational radiation because gravitational dipole radiation cannot exist. You have to have a changing acceleration. It seems to me that you don't need a planet sized mass or energy equivalent, you just need to interfere waves and switch things really quickly (we want the gravitomagnetic flux to be changing quickly) to be able to induce alternating gravitational fields. This isn't "warp drive" in my view. I don't believe that gravitoelectromagnetism is pseudoscience anymore since Gravity Probe B was able to measure the Earth's gravitational magnetic component, and also with the confirmation of gravitational waves, the gravitational equivalent of electrodynamics must be more a true reality than just equations on paper. Just imagine the impact to the world, and the potential gains, that would come from mastering gravitodynamics, as we have with electrodynamics.
« Last Edit: 08/13/2017 08:35 PM by Mulletron »
Challenge your preconceptions, or they will challenge you. - Velik

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