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#540 by oyzw on 30 Sep, 2018 00:52
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The simulation diagram of the above cavity shows that the high field strength region is not particularly close to the small end face, and the small end face generally has little difference between the radiation intensity and the large end face, and only relies on the radiation pressure of the side wall to form a weak radiation pressure on the small end face. difference. However, there is also a general radiation pressure of the large end face higher than the radiation pressure of the small end face, and the force is directed to the large end face. To maximize the radiant pressure differential, it is necessary to load a polymer or metal diaphragm to induce further migration of the high field strength region in one direction.This forum is too quiet.
So let's curiosity do it work.
To all people in this forum with EM simulators.
Please run simulations for conformal self similar case, and post results here.
PS: At a visual crossing point verfication, a good agreement with Roger's specification.
We did this way back in the day, including many other geometries. Another user named Kenjee also did some more recently. You can check his history for those. -
#541 by meberbs on 30 Sep, 2018 01:19
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Without having reproduced even one of those early designs and either proven or disproven the claims of a useable thrust, modifying and adapting design based on theoretical simulation has led to a situation where it seems each new attempt tests a new design/build sufficiently evolved and different, that they cannot even be assessed as comparable one with another, let alone be a credible test of the original build. SeeShells May have come close in her 2015 build, but time, life and criticism seem to have stalled further pursuit...
You keep claiming this about people not using the same drives, but I really don't know what you are expecting. You mentioned Shawyer's and Yang's drives. Yang's initial drive was a design that basically everyone seemed to agree was bad. Yang later retracted the original claims, so that thread is closed. Shawyer as you have said has not been helpful with facilitating replications. The drives people have been testing with have followed his advice to the extent his advice is self-consistent. It is nonsensical to ask for more unless Shawyer starts behaving more like a scientist and less like a snake oil salesman.
The baseline drive for testing has been Eaglework's design, in particular since their tests are what kicked off popular interest, as they had way more credibility than Shawyer. Most tests seem to have used their design or something closely similar. Monomorphic has gone as far as actually testing with drives built by other people.Current designs may have been overly influenced by simulations inherently based on biased models.
That statement is simply wrong. The models used have all been validated by measured resonance spectrum, and since the models for these tests are just used to predict resonance and have been shown to do so correctly, there is nothing biased about them. -
#542 by OnlyMe on 30 Sep, 2018 18:20
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Without having reproduced even one of those early designs and either proven or disproven the claims of a useable thrust, modifying and adapting design based on theoretical simulation has led to a situation where it seems each new attempt tests a new design/build sufficiently evolved and different, that they cannot even be assessed as comparable one with another, let alone be a credible test of the original build. SeeShells May have come close in her 2015 build, but time, life and criticism seem to have stalled further pursuit...
You keep claiming this about people not using the same drives, but I really don't know what you are expecting. You mentioned Shawyer's and Yang's drives. Yang's initial drive was a design that basically everyone seemed to agree was bad. Yang later retracted the original claims, so that thread is closed. Shawyer as you have said has not been helpful with facilitating replications. The drives people have been testing with have followed his advice to the extent his advice is self-consistent. It is nonsensical to ask for more unless Shawyer starts behaving more like a scientist and less like a snake oil salesman.
The baseline drive for testing has been Eaglework's design, in particular since their tests are what kicked off popular interest, as they had way more credibility than Shawyer. Most tests seem to have used their design or something closely similar. Monomorphic has gone as far as actually testing with drives built by other people.Current designs may have been overly influenced by simulations inherently based on biased models.
That statement is simply wrong. The models used have all been validated by measured resonance spectrum, and since the models for these tests are just used to predict resonance and have been shown to do so correctly, there is nothing biased about them.
meberbs,
When I said biased models, my intent was that our current understanding and interpretation, that the simulation models are based on, begin “saying” an EmDrive cannot work.., and since we have no credible theoretical model to start with, we cannot know that the resonance predicted by any model, even demonstrated within the context of experiment, has or could have anything to do with the production of any anomalous force. Mode shape and resonance have been assumed to be contributing components. An assumption that has lead to system designs that vary significantly from those early examples. Even the Eagleworks build was influenced to some extent by the same or similar assumptions.
I am not referencing experiment design. Monomorphic’s work refining his test bed and data collection, has been exceptional. I am referring only to the evolution of the design(s) of the EmDrive systems...
It was my understanding that the Eagleworks test campaign was initiated in response to Yang’s initial claim to have confirmed Shawyer’s early design and claims, but the Eagleworks drive was not a duplicate of either.
Yes Yang’s initial build and experiment was flawed and the results suspect, but her later re-evaluation based on the results of a second and substantially different build and experimental design, was also flawed. The two experiments were not tests of equivalent devices. The published information seemed no more convincing than Shawyer’s refusal to provide sufficiently detailed engineering data to reproduce any of his early work, without a significant dose of guesswork. It should have been possible to retest Yang’s first build, to confirm, her after the fact re-evaluation. The conclusions in her re-evaluation could have been experimentally confirmed. But that never happened, at least if it did, it was not publicly shared.
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#543 by meberbs on 30 Sep, 2018 19:45
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When I said biased models, my intent was that our current understanding and interpretation, that the simulation models are based on, begin “saying” an EmDrive cannot work.., and since we have no credible theoretical model to start with, we cannot know that the resonance predicted by any model, even demonstrated within the context of experiment, has or could have anything to do with the production of any anomalous force.
Again, none of this is a valid complaint about the models. It does not matter how a resonance is found, models or not. What is relevant is that models correctly predict resonance, so they are useful.Mode shape and resonance have been assumed to be contributing components. An assumption that has lead to system designs that vary significantly from those early examples. Even the Eagleworks build was influenced to some extent by the same or similar assumptions.
Literally no one has ever built an emDrive with an intent to drive it at anything but resonance, it is part of the definition of what an emDrive is. Since essentially no energy ends up in the cavity outside resonance (this is an experimental fact) it makes even less sense to think that that situation would be at all useful to test than the original concept of a self-accelerating resonant cavity. If you throw out resonance, you might as well be claiming that if you jump off a ledge (preferably a low one) and move your arms just right you will fly.It was my understanding that the Eagleworks test campaign was initiated in response to Yang’s initial claim to have confirmed Shawyer’s early design and claims, but the Eagleworks drive was not a duplicate of either.
The Eagleworks device was more similar to Shawyer's device than Yang's, and if Shawyer was actually helpful, it probably would have duplicated a Shawyer design.Yes Yang’s initial build and experiment was flawed and the results suspect, but her later re-evaluation based on the results of a second and substantially different build and experimental design, was also flawed.
This still leaves us at the point of there being absolutely no reason to think that any of Yang's designs are even remotely worthwhile to investigate.
For everything you just said, you never answered my original question: What are you expecting? Experimenters have done just about everything they reasonably can be expected to given the available constraints. There are an infinite number of things that can be tested (what about a dumbbell shaped cavity, what if the dumbbell's ends are different sizes, maybe the "ends" can be spherical, or cylindrical, or hexagonal, what about the shape and length of the connecting piece, etc.), and a finite amount of time and resources available to experimenters. If you think something else should be done to close this matter, you should be specific as to what that is, and provide a reason why it is worthwhile. (Note that the following is not a good reason: "An experimenter once got a positive result in an experiment that everyone including them agrees was a poorly designed experiment, and they themselves believe that the result was due to an error source they originally didn't account for.") -
#544 by Ricvil on 01 Oct, 2018 15:03
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Thank you Oyzw!
The simulation diagram of the above cavity shows that the high field strength region is not particularly close to the small end face, and the small end face generally has little difference between the radiation intensity and the large end face, and only relies on the radiation pressure of the side wall to form a weak radiation pressure on the small end face. difference. However, there is also a general radiation pressure of the large end face higher than the radiation pressure of the small end face, and the force is directed to the large end face. To maximize the radiant pressure differential, it is necessary to load a polymer or metal diaphragm to induce further migration of the high field strength region in one direction.This forum is too quiet.
So let's curiosity do it work.
To all people in this forum with EM simulators.
Please run simulations for conformal self similar case, and post results here.
PS: At a visual crossing point verfication, a good agreement with Roger's specification.
We did this way back in the day, including many other geometries. Another user named Kenjee also did some more recently. You can check his history for those.
I have some questions to this forum.
Are we seeing the Lorentzian shaped cavity divided in two domains?
Does the first domain contains a slow bright bessel mode near the small end?
Does the second domain contains a fast dark bessel "X" mode near the large end?
IMHO the possible domain segregation explanation can be founded in the attached "anderson.pdf" , and I put a screenshot of the specific point in question.
The almost monocromatic "X" wave has beeing modeled in the other attachment, and perhaps can be possible to link the cavity Fano resonance, with phase inversion, response acting as a kind of "kdp" cristal response described in the article.
PS: Adding an article connecting Zak/Berry phases, Wannier functions and Wyckoff position to help the understanding the idea of radius inversion symmetry induced "segregated zones" by reflection positivity.
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#545 by X_RaY on 01 Oct, 2018 20:14
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I do not think that is caused by the effects you mentioned. It might be possible to modify the described mathematics to describe the problem based on different propagation angles and phase matching. However, the boundary conditions of the conductive walls must be satisfied. The most common way to describe the field pattern, even within a trombone shape line, is to use stationary waves at individual frequencies, which leads to this pattern exactly. The image you show should be based on a self-resonance calculation or an FEA analysis that produces resonance at a certain frequency, i.e. an Eigen-mode. The analysis solves Maxwell's equations to calculate the resonant frequency and the pattern itself. There is nothing new at this point. But if you think you found a way to explain a possible net force, based on the inner EM field acting on the cavity structure that could move the entire structure in a preferred direction in free space, you should explain your ideas in more detail, at best with mathematical formulas.
Thank you Oyzw!
The simulation diagram of the above cavity shows that the high field strength region is not particularly close to the small end face, and the small end face generally has little difference between the radiation intensity and the large end face, and only relies on the radiation pressure of the side wall to form a weak radiation pressure on the small end face. difference. However, there is also a general radiation pressure of the large end face higher than the radiation pressure of the small end face, and the force is directed to the large end face. To maximize the radiant pressure differential, it is necessary to load a polymer or metal diaphragm to induce further migration of the high field strength region in one direction.This forum is too quiet.
So let's curiosity do it work.
To all people in this forum with EM simulators.
Please run simulations for conformal self similar case, and post results here.
PS: At a visual crossing point verfication, a good agreement with Roger's specification.
We did this way back in the day, including many other geometries. Another user named Kenjee also did some more recently. You can check his history for those.
I have some questions to this forum.
Are we seeing the Lorentzian shaped cavity divided in two domains?
Does the first domain contains a slow bright bessel mode near the small end?
Does the second domain contains a fast dark bessel "X" mode near the large end?
IMHO the possible domain segregation explanation can be founded in the attached "anderson.pdf" , and I put a screenshot of the specific point in question.
The almost monocromatic "X" wave has beeing modeled in the other attachment, and perhaps can be possible to link the cavity Fano resonance, with phase inversion, response acting as a kind of "kdp" cristal response described in the article. -
#546 by cvbn on 01 Oct, 2018 21:31
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Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf -
#547 by rq3 on 01 Oct, 2018 22:38
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Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
A really inefficient ion engine. -
#548 by Ricvil on 01 Oct, 2018 22:53
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Dear X_Ray,
I do not think that is caused by the effects you mentioned. It might be possible to modify the described mathematics to describe the problem based on different propagation angles and phase matching. However, the boundary conditions of the conductive walls must be satisfied. The most common way to describe the field pattern, even within a trombone shape line, is to use stationary waves at individual frequencies, which leads to this pattern exactly. The image you show should be based on a self-resonance calculation or an FEA analysis that produces resonance at a certain frequency, i.e. an Eigen-mode. The analysis solves Maxwell's equations to calculate the resonant frequency and the pattern itself. There is nothing new at this point. But if you think you found a way to explain a possible net force, based on the inner EM field acting on the cavity structure that could move the entire structure in a preferred direction in free space, you should explain your ideas in more detail, at best with mathematical formulas.
Thank you Oyzw!
The simulation diagram of the above cavity shows that the high field strength region is not particularly close to the small end face, and the small end face generally has little difference between the radiation intensity and the large end face, and only relies on the radiation pressure of the side wall to form a weak radiation pressure on the small end face. difference. However, there is also a general radiation pressure of the large end face higher than the radiation pressure of the small end face, and the force is directed to the large end face. To maximize the radiant pressure differential, it is necessary to load a polymer or metal diaphragm to induce further migration of the high field strength region in one direction.This forum is too quiet.
So let's curiosity do it work.
To all people in this forum with EM simulators.
Please run simulations for conformal self similar case, and post results here.
PS: At a visual crossing point verfication, a good agreement with Roger's specification.
We did this way back in the day, including many other geometries. Another user named Kenjee also did some more recently. You can check his history for those.
I have some questions to this forum.
Are we seeing the Lorentzian shaped cavity divided in two domains?
Does the first domain contains a slow bright bessel mode near the small end?
Does the second domain contains a fast dark bessel "X" mode near the large end?
IMHO the possible domain segregation explanation can be founded in the attached "anderson.pdf" , and I put a screenshot of the specific point in question.
The almost monocromatic "X" wave has beeing modeled in the other attachment, and perhaps can be possible to link the cavity Fano resonance, with phase inversion, response acting as a kind of "kdp" cristal response described in the article.
I'm trying to explain my point of view.
I had constantly pointing to the role of a space time conformal symmetry called "radius inversion".
I had indirectly pointed (by some ugly drawings )the surface of conical cavity (with conical or flat endplates) are symmetric by this conformal symmetry, like a parity symmetry.
No one has made a direct question about this symmetry.
I'm trying to show how these boundary conditions (almost PEC boundary conditions) can introduce a Berry phase on the system, and all consequences of that (look the attachment about Zak/Berry phases introduced in the PS of my last post for example).
I had put a explicity Lorentizian function in a recent post, obtained from the conformal symmetry, and I had described it's relation with the observed "cutoff points".
My intention was to receive a feedback, be a confirmation or a negative answer, but I had no answer about that.
You do need at least two people for a conversation. -
#549 by spupeng7 on 02 Oct, 2018 01:14
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rq3,Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
A really inefficient ion engine.
it cannot be an ion engine inside a faraday cage. -
#550 by spupeng7 on 02 Oct, 2018 01:22
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Ricvil,Meantime, causality should be independent of spatial geometry for two reasons, firstly because it is the consequence of interactions between mass and secondly because space itself has no substance with which to retain any specific geometry.
Causality is linked to the speed of light. Experiments show that this really is the speed limit. As a result you have to take into account distance between object when determining causality. You probably can rearrange things to hide this, but no matter what, something in your equations will be equivalent to a distance term, that or your theory would simply be inconsistent with experiment. Space can have geometry even if it doesn't have substance, for example, it could be shaped into a loop, so things that travel in a straight line end up back where they started. In special relativity the spacetime is a shape called "Minkowski" which basically means that space is flat, but interacts in a special way with time.It is not my intention to confuse but to try to resolve some of these very confused issues which are, to my mind, hindering the progress of physics.
You keep insisting that physics doesn't make sense, while demonstrating that you don't know what physics actually says. The "issues" you are bringing up are not "confused" for people who actually study them.
thankyou for the reference to arXiv papers which are forever beyond my ken. I cannot fathom their logic one bit. At risk of sounding rude, it matters not how many tripple spin mathematical backflips we do, none of it gives us a mechanism by which matter interacts with the space that it is in. Where is the mechanism of interaction between matter and empty space which could possibly satisfy conservation of momentum? That would be an ether. In my opinion separation between objects is not something we can specify without using a complex conjugate for our measure of time which is moderated by the relative velocity of those objects.
Maybe causality can be better defined without spatial geometry. Causality is a term referring to the interaction of things as a cause of the development of circumstance, without a real sequence for events which depends upon the inevitable speed of light across which interaction must occur, there is separation of effect from cause. The strict set of relations described by orthogonal spatial dimensions cannot be true except within the space local to a single clock. If you abandon that absurdity and accept that time has a complex conjugate then causality no longer requires "unreal electromagnetic frontwaves". You can find direct causality in the influence that the acceleration of any charge has on the location of all other charges, proportional to a separation which remains covariant.
The point I am trying to make about time is that our arguments are based on insufficient reason until we understand that there is no common scalar time at disparate points in space, except from a limited and unique set of perspectives. And so, all else fails, along with our ability to understand how purchase for acceleration can be gained against the distant universe.
meberbs,
my use of the word covariant is valid, as I have soundly demonstrated. I do not think it should be constantly questioned because it is a fundamental descriptor used in relativity for a century and more.
See: https://forum.nasaspaceflight.com/index.php?topic=45824.msg1851431#msg1851431
It should be clear that I attempt to clarify a dangerously mysterious subject, as best I can. Relativity deserves disciplined creative thought, properly argued, how could we devote ourselves to it by lesser means. Personal attacks such as accusations of poor intent should be taken to the moderator.
dustinthewind,
the complex time I propose has no perpendicular, it is a separation between objects or charges which varies with their relative velocity. I propose this because distance, in 3D space and scalar time alone, is not covariant. If we are to discuss separation, which is what physical interaction is regulated by, then we need to raise our game and define it succinctly. Complex time allows us to define separation as divergence of location in the proper time of the observer, which is covariant and specifies ct, which converts readily into meters in the perspective of that observer.
Thank you all for your good questions.
Can I take your silence as agreement? -
#551 by demofsky on 02 Oct, 2018 03:24
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You are missing the point. If it is propellantless there is considerable mass savings which have to be taken into account in overall system efficiency. Especially for long or heavy flights (i.e. cargo to Mars) where you would need a lot of propellant.Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
A really inefficient ion engine.
Also, can we say very early days on this? To me tweaking dielectrics is a walk in the park compared to, say, trying to build a positron drive.
It goes without saying we need independent verification of this effect - which seems to be no small thing in this field! - but this is a straightforward apparatus and could be an excellent undergraduate project. -
#552 by Mark7777777 on 02 Oct, 2018 03:47
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Estes Park results summary:
https://www.centauri-dreams.org/2018/09/28/small-provocative-workshop-on-propellantless-propulsion/
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#553 by meberbs on 02 Oct, 2018 06:32
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Can I take your silence as agreement?
No, you cannot. It has only been a couple days, and I missed that the post that starts out addressed to Ricvil was also responding to me.my use of the word covariant is valid, as I have soundly demonstrated. I do not think it should be constantly questioned because it is a fundamental descriptor used in relativity for a century and more.
It has been used for over a century with a different meaning than you have assigned to it. The previous post you linked a quote showing Einstein using it correctly, and in contrast to your usage.
See: https://forum.nasaspaceflight.com/index.php?topic=45824.msg1851431#msg1851431It should be clear that I attempt to clarify a dangerously mysterious subject, as best I can.
Except all of those adjectives you just used are subjective and irrelevant. (Also, relativity is only mysterious to people who haven't studied it)Relativity deserves disciplined creative thought, properly argued, how could we devote ourselves to it by lesser means.
Yet you are turning this into a meta-discussion, and ignoring the previous questions that you said you would respond to.Personal attacks such as accusations of poor intent should be taken to the moderator.
This sentence is a perfect example of itself, and on its own is grounds for deletion of the whole post. (I would report to moderator, but don't like making the mods read this thread)
Also,I cannot fathom their logic one bit. At risk of sounding rude, it matters not how many tripple spin mathematical backflips we do,
Saying that you don't understand something and then therefore concluding that it doesn't answer your questions is more than a bit inappropriate. You can ask for clarification, but outright dismissal for your own lack of understanding is inappropriate. -
#554 by Monomorphic on 02 Oct, 2018 10:39
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Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
After having read through most of the paper, the first thing that sticks out for me is they used twisted supply wires and no liquid metal contacts. How many times have we seen this arrangement produce false positives?
"The supply wires had been twisted [1] to reduce electromagnetic effects (Lorentz force etc.) This was done carefully as to not influence the system and provide torque. Nevertheless, the theoretical contribution, with respect to the actual supplied current, would not contribute to an observable effect. Furthermore, to obtain a correct measurement, it had to be assured that the supply conductors were routed a sufficient distance as not to affect the load cell of the digital scale (by electromagnetic field disturbances.)"
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#555 by demofsky on 02 Oct, 2018 11:07
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Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
After having read through most of the paper, the first thing that sticks out for me is they used twisted supply wires and no liquid metal contacts. How many times have we seen this arrangement produce false positives?
Could you remind us why this might be an issue? The wires stiffening due to high voltages? Thanks! -
#556 by emdrive1 on 02 Oct, 2018 11:37
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Electrostatic accelerated electrons within information horizons exert bidirectional propellant-less thrust:
http://vixra.org/pdf/1809.0579v1.pdf
After having read through most of the paper, the first thing that sticks out for me is they used twisted supply wires and no liquid metal contacts. How many times have we seen this arrangement produce false positives?
"The supply wires had been twisted [1] to reduce electromagnetic effects (Lorentz force etc.) This was done carefully as to not influence the system and provide torque. Nevertheless, the theoretical contribution, with respect to the actual supplied current, would not contribute to an observable effect. Furthermore, to obtain a correct measurement, it had to be assured that the supply conductors were routed a sufficient distance as not to affect the load cell of the digital scale (by electromagnetic field disturbances.)"
They couldn't reverse direction of thrust based on McCulloch's theory if it was a false positives signal. -
#557 by Monomorphic on 02 Oct, 2018 12:38
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They couldn't reverse direction of thrust based on McCulloch's theory if it was a false positives signal.
I'm not so sure about that, but I admit, i'm still trying to wrap my mind around the experiment. We know false positive signals can reverse, but the way the reversal is obtained in this case "by attenuating the associated horizon boundary (Unruh) radiations within the Rindler zone" is not very clear to me. They seem to have placed a conductive material into the "information boundary zone," and "when a conductive material that was electrically insulated from the cathode had been inserted into the area at any
position, a full force reversal was observed." The "at any position" may be a clue here.
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#558 by Monomorphic on 02 Oct, 2018 12:42
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Could you remind us why this might be an issue? The wires stiffening due to high voltages? Thanks!
Professor Yang, Dave Distler, and my early experiments showed that milli-Newtons of force can be generated by the flexing of the cables when they are supplied with kV power sources - enough that it would swamp everything else. -
#559 by Notsosureofit on 02 Oct, 2018 15:45
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FYI:
https://physicstoday.scitation.org/doi/full/10.1063/PT.3.4037?utm_source=Physics%20Today&utm_medium=email&utm_campaign=9893039_Q%20-%20October%202018&dm_i=1Y69,5W1IN,E1MTSN,N1DFQ,1
"Free-falling nanoparticle helps to detect tiny forces"
