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#1220
by
JohnFornaro
on 25 Jul, 2019 15:36
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If you have nothing to say, please don't waste anyone's time by posting random pictures that you refuse to explain.
Took the words right outta my mouth.
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#1221
by
Chris Bergin
on 26 Jul, 2019 18:13
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I'm sure, but there's a civil way to say it. The forum rules apply to all, so I expect better from experienced and respected members such as Meberbs and all.
When experienced members head that down route new members think it's fine for them to do likewise and then you have a snowball effect.
So don't.
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#1222
by
Bob012345
on 26 Jul, 2019 18:35
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If that's right then it might be that light is the universes way of keeping track of every change in the magnetic field in the universe.
Or that light is depositing the magnetic field over the universe as it travels.
Speaking of off topic, you have repeated this observation of yours multiple times in multiple threads. It really does not contribute anything to this topic, and it isn't an interesting observation, because it is well known that anytime charges accelerate, they emit radiation, and this radiation propagating at the speed of light therefore coincides with the speed of light delayed propagation of information that the charge has accelerated. The energy and momentum carried by the radiation is what allows energy and momentum to be balanced when distant charges interact with the change in the fields. Your observation about the magnetic field is a partial recognition of what happens hear, but you are missing that the change in the electric field is also communicated, and that for this context, you really would be better off considering that the electromagnetic fields are a single object, since whether they are electric or magnetic fields depends on the reference frame.
What is interesting is subjective. It was on topic because it was discussed if the magnetic field drops off as 1/r^2. In the biot savart equation for a single charge the magnetic field does.
Also whats interesting is that because light is from the magnetic field then dQ/dt radiation is a separate matter. 
It would propagate with the electric field in the direction of travel, very unlike normal light. I think generally of much less magnitude but I think that might depend on the device that generates it and the magnitude of change in charge.
As I already explained to you:
https://forum.nasaspaceflight.com/index.php?topic=36911.msg1917955#msg1917955
There is no such thing as any form of electromagnetic radiation where the electric field is partially in the direction of propagation. You are confusing the moving of the electric field because a charge is moving with the actual radiation.
This was some what exotic and I probably didn't have to include this.
I was referring to the idea that you can make a phased array that seems to radiate in a direction in which radiation should not radiate. In the direction of charge motion. Normally radiation is perpendicular to the direction of charge motion. The electric field would be in the direction of travel. image below.
topic is here: https://forum.nasaspaceflight.com/index.php?topic=36911.msg1919418#msg1919418 but goes back a ways.
I don't think its all that important here, but I don't think anyone knows what is important when it comes to how propulsion is being induced if it is and even if propulsion is being induced so exploration of topics is some what natural. Inhibiting it inhibits creative thinking.
I recently read several papers showing how waves with electric fields along the direction of propagation, called longitudinal waves, can exist and have been measured. Basically, when the Lorentz Gauge is not used, such waves come out of Maxwell's equations. Here are just a few references to search.
Reed, "Unravelling the potentials puzzle and corresponding case for the scalar longitudinal electrodynamic wave"
Hively, "Implications of a New Electrodynamic Theory"
Hively, Giakos, "Toward a more complete electrodynamic theory"
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#1223
by
meberbs
on 26 Jul, 2019 20:39
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I recently read several papers showing how waves with electric fields along the direction of propagation, called longitudinal waves, can exist and have been measured. Basically, when the Lorentz Gauge is not used, such waves come out of Maxwell's equations. Here are just a few references to search.
...
Using different gauges has exactly 0 effect on the fields. Gauge freedom only affects the electric potential and the magnetic vector potential, but those are not real, physically measurable things,* just mathematical conveniences. If you get any difference in the fields due to different gauges, it means you did the math wrong.
* If you read that and say "but wait, I have a voltmeter sitting on my desk," keep in mind that voltmeters measure potential
difference. This inherently subtracts off the gauge freedom to result in something physically measurable. This need for a reference point for any voltage measurement is basically what gauge freedom means.
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#1224
by
1
on 26 Jul, 2019 22:14
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Perhaps the EM-drive threads have run their course.
In the seven or so years since the first thread was started, we're precisely in the same spot where we were before. Much of the dialogue over the last couple of threads has been a lot of back and forth, over ground already well-trodden, and with increasing exasperation from many folks in here. If these threads are to continue, perhaps a re-grounding of sorts might improve quality.
I would suggest refocusing on what is, in my eyes, the crown jewel of these threads; Monomorphic's homemade build. Not because I personally believe any EM-drive like device will ever work as advertised (I don't), but because Monomorphic has essentially been running a master class on small signal isolation and error detection/mitigation; the lessons of which are applicable to anyone in any number of fields.
I think both the experimentalists and theorists among us would be happier to have something more real-world to focus on, and it would serve as a better dividing line for what is and isn't on topic / constructive regarding some of the more, well, repetitive posts as of late.
Lock this and start thread 12 with a new scope?
Lock this in favor of Starlab thread 1?
Keep this thread on its current Thelma & Louise-esque trajectory?
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#1225
by
JohnFornaro
on 27 Jul, 2019 12:32
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In the seven or so years since the first thread was started, we're precisely in the same spot where we were before.
In addition, we have lost the input of the folks who are building hardware, and reporting their results. Perhaps the experimenters have drawn conclusions?
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#1226
by
Bob012345
on 27 Jul, 2019 17:41
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I recently read several papers showing how waves with electric fields along the direction of propagation, called longitudinal waves, can exist and have been measured. Basically, when the Lorentz Gauge is not used, such waves come out of Maxwell's equations. Here are just a few references to search.
...
Using different gauges has exactly 0 effect on the fields. Gauge freedom only affects the electric potential and the magnetic vector potential, but those are not real, physically measurable things,* just mathematical conveniences. If you get any difference in the fields due to different gauges, it means you did the math wrong.
* If you read that and say "but wait, I have a voltmeter sitting on my desk," keep in mind that voltmeters measure potential difference. This inherently subtracts off the gauge freedom to result in something physically measurable. This need for a reference point for any voltage measurement is basically what gauge freedom means.
You don't get any difference in the E and B fields. There are new fields. People have measured longitudinal E field waves. Also, I recently read several more papers from a variety of scientists saying exactly the opposite of what you just said about the vector and scalar potentials being mere contrivances and that they should be considered the more fundamental things. That's the view in quantum mechanics and that seemed to be Feynman's view. One is not forced to make the vector and scalar potentials dependent on each other. They can be independent. So it's not just me.
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#1227
by
Bob012345
on 27 Jul, 2019 18:36
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Perhaps the EM-drive threads have run their course.
In the seven or so years since the first thread was started, we're precisely in the same spot where we were before. Much of the dialogue over the last couple of threads has been a lot of back and forth, over ground already well-trodden, and with increasing exasperation from many folks in here. If these threads are to continue, perhaps a re-grounding of sorts might improve quality.
I would suggest refocusing on what is, in my eyes, the crown jewel of these threads; Monomorphic's homemade build. Not because I personally believe any EM-drive like device will ever work as advertised (I don't), but because Monomorphic has essentially been running a master class on small signal isolation and error detection/mitigation; the lessons of which are applicable to anyone in any number of fields.
I think both the experimentalists and theorists among us would be happier to have something more real-world to focus on, and it would serve as a better dividing line for what is and isn't on topic / constructive regarding some of the more, well, repetitive posts as of late.
Lock this and start thread 12 with a new scope?
Lock this in favor of Starlab thread 1?
Keep this thread on its current Thelma & Louise-esque trajectory?
Keep it. People obviously post here because they want to.
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#1228
by
MathewOrman
on 28 Jul, 2019 13:49
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#1229
by
TheTraveller
on 28 Jul, 2019 15:06
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Email received from Roger Shawyer.
Seems a lot of new Flight Thruster test, design & engineering data are being released. Original data here:
http://www.emdrive.com/flightprogramme.htmlInteresting times ahead.
People may like to read the paper I am presenting at IAC19 in Washington on 25 Oct.
There will be a lot of information in it on our original Flight Thruster, which might be helpful.
The patent for first generation EmDrive has now elapsed, and the Boeing agreements are no longer valid, so design information will be included.
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#1230
by
Bob012345
on 28 Jul, 2019 15:21
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#1231
by
MathewOrman
on 28 Jul, 2019 15:51
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Why waist time building a device which has no physics that supports it?
Roger Shawyer has publicly proven that it is a fraud by publishing of this video where his devices rotates showing thrust million times greater than what he claimed... :-)
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#1232
by
TheTraveller
on 28 Jul, 2019 16:21
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Why waist time building a device which has no physics that supports it?
Roger Shawyer has publicly proven that it is a fraud by publishing of this video where his devices rotates showing thrust million times greater than what he claimed... :-)
Claimed thrust for the Demonstrator run was 96mN, ~9.8gm, at 334Wrf input with a 8.2gm frictional rotation load. Effective thrust ~1.6gm.
http://www.emdrive.com/testnotes.pdf
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#1233
by
Vlad Kri
on 28 Jul, 2019 17:33
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Do not despair guys, the Germans will soon say their weighty word. They will confirm that there is traction. And the fun goes on. Particularly interesting will be the impulse in the opposite direction at the time of inclusion. Just waiting, smiling and waving.
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#1234
by
TheTraveller
on 28 Jul, 2019 20:59
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Why waist time building a device which has no physics that supports it?
Roger Shawyer has publicly proven that it is a fraud by publishing of this video where his devices rotates showing thrust million times greater than what he claimed... :-)
Claimed thrust for the Demonstrator run was 96mN, ~9.8gm, at 334Wrf input with a 8.2gm frictional rotation load. Effective thrust ~1.6gm.
http://www.emdrive.com/testnotes.pdf
So it says but the video shows something else not to mention that after he switched the power off the device actually began to gain speed... Roger Fraudster... :-)
Roger's CEAS 2009 paper explains why that happened. Page 9 onward.
http://www.emdrive.com/CEAS2009paper.docNote the rate of acceleration while the drive was powered and note no movement was induced by the circulating coolant before resonance lock.
Movement started then the control system obtained resonance lock.
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#1235
by
meberbs
on 29 Jul, 2019 07:30
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#1236
by
meberbs
on 29 Jul, 2019 09:01
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I recently read several papers showing how waves with electric fields along the direction of propagation, called longitudinal waves, can exist and have been measured. Basically, when the Lorentz Gauge is not used, such waves come out of Maxwell's equations. Here are just a few references to search.
...
Using different gauges has exactly 0 effect on the fields. Gauge freedom only affects the electric potential and the magnetic vector potential, but those are not real, physically measurable things,* just mathematical conveniences. If you get any difference in the fields due to different gauges, it means you did the math wrong.
* If you read that and say "but wait, I have a voltmeter sitting on my desk," keep in mind that voltmeters measure potential difference. This inherently subtracts off the gauge freedom to result in something physically measurable. This need for a reference point for any voltage measurement is basically what gauge freedom means.
You don't get any difference in the E and B fields. There are new fields.
What "new fields?" I looked through one of the papers you mentioned previously (Implications of a New Electrodynamic Theory), and it talks about no other fields. It starts with making the statement I made about how you can freely add a term of a certain form to the potentials without changing the fields, and by the end is describing differences in the E-field as a result of the changes in gauge. The existence of a flaw in the logic is obvious and finding the exact spot doesn't seem particularly worthwhile. At a glance, it seems to be a problem with not using a valid gauge function either by not taking the appropriate derivatives before adding it in, or by using a recursive definition which confuses things enough to make it look like you can do a certain manipulation, but you are actually breaking something when you do it. (You can do something similar with basic algebra "proving" 1=0 by doing a bunch of perfectly legitimate steps, but ignoring that you started with an assumption that causes one of your steps to divide by 0.)
People have measured longitudinal E field waves.
No, they haven't. You provided no supporting evidence for this claim that is incompatible with the well tested theory of electromagnetism. It is on you to provide evidence to support your claim, all I can do from my end is say that you are wrong. Whether that is because of flaws in the experiments, your misunderstanding of whatever you read, because there simply is no supporting evidence for your statement, or some other option, I can't say.
Also, I recently read several more papers from a variety of scientists saying exactly the opposite of what you just said about the vector and scalar potentials being mere contrivances and that they should be considered the more fundamental things. That's the view in quantum mechanics and that seemed to be Feynman's view. One is not forced to make the vector and scalar potentials dependent on each other. They can be independent. So it's not just me.
What you just said indicates to me that you did not understand what I said, because it is not about the potentials being dependent on each other, but about how there is an unavoidable degree of freedom in the potentials that is devoid of physical meaning.
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#1237
by
dustinthewind
on 30 Jul, 2019 07:44
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I recently read several papers showing how waves with electric fields along the direction of propagation, called longitudinal waves, can exist and have been measured. Basically, when the Lorentz Gauge is not used, such waves come out of Maxwell's equations. Here are just a few references to search.
...
Using different gauges has exactly 0 effect on the fields. Gauge freedom only affects the electric potential and the magnetic vector potential, but those are not real, physically measurable things,* just mathematical conveniences. If you get any difference in the fields due to different gauges, it means you did the math wrong.
* If you read that and say "but wait, I have a voltmeter sitting on my desk," keep in mind that voltmeters measure potential difference. This inherently subtracts off the gauge freedom to result in something physically measurable. This need for a reference point for any voltage measurement is basically what gauge freedom means.
You don't get any difference in the E and B fields. There are new fields.
What "new fields?" I looked through one of the papers you mentioned previously (Implications of a New Electrodynamic Theory), and it talks about no other fields. It starts with making the statement I made about how you can freely add a term of a certain form to the potentials without changing the fields, and by the end is describing differences in the E-field as a result of the changes in gauge. The existence of a flaw in the logic is obvious and finding the exact spot doesn't seem particularly worthwhile. At a glance, it seems to be a problem with not using a valid gauge function either by not taking the appropriate derivatives before adding it in, or by using a recursive definition which confuses things enough to make it look like you can do a certain manipulation, but you are actually breaking something when you do it. (You can do something similar with basic algebra "proving" 1=0 by doing a bunch of perfectly legitimate steps, but ignoring that you started with an assumption that causes one of your steps to divide by 0.)
People have measured longitudinal E field waves.
No, they haven't. You provided no supporting evidence for this claim that is incompatible with the well tested theory of electromagnetism. It is on you to provide evidence to support your claim, all I can do from my end is say that you are wrong. Whether that is because of flaws in the experiments, your misunderstanding of whatever you read, because there simply is no supporting evidence for your statement, or some other option, I can't say.
Also, I recently read several more papers from a variety of scientists saying exactly the opposite of what you just said about the vector and scalar potentials being mere contrivances and that they should be considered the more fundamental things. That's the view in quantum mechanics and that seemed to be Feynman's view. One is not forced to make the vector and scalar potentials dependent on each other. They can be independent. So it's not just me.
What you just said indicates to me that you did not understand what I said, because it is not about the potentials being dependent on each other, but about how there is an unavoidable degree of freedom in the potentials that is devoid of physical meaning.
Aharonov–Bohm effect
https://en.wikipedia.org/wiki/Aharonov%E2%80%93Bohm_effectPotentials vs. fields
It is generally argued that Aharonov–Bohm effect illustrates the physicality of electromagnetic potentials, Φ and A, in quantum mechanics. Classically it was possible to argue that only the electromagnetic fields are physical, while the electromagnetic potentials are purely mathematical constructs, that due to gauge freedom aren't even unique for a given electromagnetic field.
However, Vaidman has challenged this interpretation by showing that the AB effect can be explained without the use of potentials so long as one gives a full quantum mechanical treatment to the source charges that produce the electromagnetic field.[9] According to this view, the potential in quantum mechanics is just as physical (or non-physical) as it was classically. Aharonov, Cohen, and Rohrlich responded that the effect may be due to a local gauge potential or due to non-local gauge-invariant fields.[10]
...
Locality of electromagnetic effects
The Aharonov–Bohm effect shows that the local E and B fields do not contain full information about the electromagnetic field, and the electromagnetic four-potential, (Φ, A), must be used instead. By Stokes' theorem, the magnitude of the Aharonov–Bohm effect can be calculated using the electromagnetic fields alone, or using the four-potential alone. But when using just the electromagnetic fields, the effect depends on the field values in a region from which the test particle is excluded. In contrast, when using just the electromagnetic four-potential, the effect only depends on the potential in the region where the test particle is allowed. Therefore, one must either abandon the principle of locality, which most physicists are reluctant to do, or accept that the electromagnetic four-potential offers a more complete description of electromagnetism than the electric and magnetic fields can. On the other hand, the AB effect is crucially quantum mechanical; quantum mechanics is well-known to feature non-local effects (albeit still disallowing superluminal communication), and Vaidman has argued that this is just a non-local quantum effect in a different form.[9]
In classical electromagnetism the two descriptions were equivalent. With the addition of quantum theory, though, the electromagnetic potentials Φ and A are seen as being more fundamental. [13] Despite this, all observable effects end up being expressible in terms of the electromagnetic fields, E and B. This is interesting because, while you can calculate the electromagnetic field from the four-potential, due to gauge freedom the reverse is not true.
...
Monopoles and Dirac strings
The magnetic Aharonov–Bohm effect is also closely related to Dirac's argument that the existence of a magnetic monopole can be accommodated by the existing magnetic source-free Maxwell's equations if both electric and magnetic charges are quantized.
A magnetic monopole implies a mathematical singularity in the vector potential, which can be expressed as a Dirac string of infinitesimal diameter that contains the equivalent of all of the 4πg flux from a monopole "charge" g. The Dirac string starts from, and terminates on, a magnetic monopole.
This last paragraph above reminds me of the 1/r^2 behavior of the magnetic field from a single charge in the Biot-Savart law.
Global action vs. local forces
Similarly, the Aharonov–Bohm effect illustrates that the Lagrangian approach to dynamics, based on energies, is not just a computational aid to the Newtonian approach, based on forces. Thus the Aharonov–Bohm effect validates the view that forces are an incomplete way to formulate physics, and potential energies must be used instead. In fact Richard Feynman complained[citation needed] that he had been taught electromagnetism from the perspective of electromagnetic fields, and he wished later in life he had been taught to think in terms of the electromagnetic potential instead, as this would be more fundamental. In Feynman's path-integral view of dynamics, the potential field directly changes the phase of an electron wave function, and it is these changes in phase that lead to measurable quantities.
Is this below the scalar electric potential wave?
Electric effect
Just as the phase of the wave function depends upon the magnetic vector potential, it also depends upon the scalar electric potential. By constructing a situation in which the electrostatic potential varies for two paths of a particle, through regions of zero electric field, an observable Aharonov–Bohm interference phenomenon from the phase shift has been predicted; again, the absence of an electric field means that, classically, there would be no effect.
From the Schrödinger equation, the phase of an eigenfunction with energy E goes as {\displaystyle e^{-iEt/\hbar }} {\displaystyle e^{-iEt/\hbar }}. The energy, however, will depend upon the electrostatic potential V for a particle with charge q. In particular, for a region with constant potential V (zero field), the electric potential energy qV is simply added to E, resulting in a phase shift:
{\displaystyle \Delta \phi =-{\frac {qVt}{\hbar }},} \Delta \phi =-{\frac {qVt}{\hbar }},
where t is the time spent in the potential.
The initial theoretical proposal for this effect suggested an experiment where charges pass through conducting cylinders along two paths, which shield the particles from external electric fields in the regions where they travel, but still allow a varying potential to be applied by charging the cylinders. This proved difficult to realize, however. Instead, a different experiment was proposed involving a ring geometry interrupted by tunnel barriers, with a bias voltage V relating the potentials of the two halves of the ring. This situation results in an Aharonov–Bohm phase shift as above, and was observed experimentally in 1998.[27]
I want to say no that this above is a little different but related maybe. This article seems a bit more related but not sure its the best source.
https://www.researchgate.net/publication/327447483_Scalar_WavesScalar Waves
Bahman Zohuri
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#1238
by
Bob012345
on 30 Jul, 2019 17:35
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#1239
by
meberbs
on 30 Jul, 2019 17:52
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https://www.newscientist.com/article/2169809-impossible-em-drive-doesnt-seem-to-work-after-all/
An old and admittedly flawed test.
What "admitted flaws" are there in the test that article is about? That is not talking about the old test that had a Q orders of magnitude too low.
As I understand it, the Woodward team responded to Tajmar's null test showing how the Dresden team didn't follow proper protocol, didn't understand what they were doing and ruined the device.
https://drive.google.com/file/d/1iMkqxPFXFBFT3rbmRrXmrtGlrBdZWmNh/view
The article is about the emDrive, and has literally nothing to do with Woodward's device at all.
This is the wrong thread to go into Woodward's complaints about the test of Woodward's device, so I won't respond to what you just said about that in detail, but you are taking a one sided perspective, and not considering Woodward's responsibility to actually sufficiently explain how to run his device.
It would propagate with the electric field in the direction of travel, very unlike normal light. I think generally of much less magnitude but I think that might depend on the device that generates it and the magnitude of change in charge.