-
#80 by X_RaY on 30 Jun, 2018 21:12
-
The joint of different metals and its contact potential is only of interest for different temperatures between the contact points because of the Seebeck effect.I'm up to browser bookmark 414 in this blog. I really need a criteria to enable me to get on with my life!
If The Traveller can't make this work, nobody can: he does seem to have a hotline to Shawyer, and talks a decent game on RF engineering, though I suppose metalwork skills (as above) etc are not a given.
I will try and make myself quit worrying if there is nothing forthcoming from TT this year, or on another announced schedule.
I would regard a positive result from Monomorphic as equally definitive in the opposite direction.
So no pressure....
Hi Rert,
Still waiting for the Silver Epoxy. Seems the supplier had no stock when I ordered. Don't want to clean the edge and outer surface before I have the epoxy and then have it start to oxidize.
As for forming over the flower pot, some of the hoop ring are installed internally, help in position with hot glue, to make the form much stiffer. Then more hoop rings are used externally to form and hold the copper frustum in place. Have done this before, so know it can be done fairly easily. The hoop rings are the trick.
Between that I have installed new side and back fencing plus rebuilding bedroom furniture for a friends son. So no rest.
You don't have to worry about Copper oxidation. Copper oxidizes very slowly at room temperature, in dry air. Conductive epoxy contains Silver and will produce a contact potential with Copper. Another method you might want to look into is to use Copper rivets.
To use copper rivets would lead to high conductive but located contact points and do not fit to TT's ( &"Roger's") definition of a good cavity since he states that even small scratches (some µm depth) will lower the Q of the cavity to much.
https://forum.nasaspaceflight.com/index.php?topic=42978.msg1719903#msg1719903
However it is possible to weld the copper wall. I think an expert for such a welding process would be necessary to make the seam, but it is feasible.
A weld seam could be abraded and polished adequately.
Picture source:
https://www.kupferinstitut.de/fileadmin/user_upload/kupferinstitut.de/de/Documents/Shop/Verlag/Downloads/Verarbeitung/i012.pdf
Sorry the text is written in german language but i am sure you will find something similar in english when you search for.
-
#81 by scienceguy on 01 Jul, 2018 22:28
-
Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
-
#82 by VAXHeadroom on 01 Jul, 2018 22:43
-
Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
Nobody has a generally accepted theory of how an EmDrive actually would work at the physical level. However, one thing I think I can say that most if not all will agree on, is that the wave interaction would look nothing like that - it is WAY WAY more complex. The systems are sized to produce standing waves at resonant frequencies within the cavity. The TE013 mode which is the predominant system people are trying essentially produces 3 stacked toroidal standing waves. But how those waves move within the cavity, and how they interact with the cavity walls and/or the outside world is the subject of several years debate on this forum! -
#83 by aero on 02 Jul, 2018 00:52
-
Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
Nobody has a generally accepted theory of how an EmDrive actually would work at the physical level. However, one thing I think I can say that most if not all will agree on, is that the wave interaction would look nothing like that - it is WAY WAY more complex. The systems are sized to produce standing waves at resonant frequencies within the cavity. The TE013 mode which is the predominant system people are trying essentially produces 3 stacked toroidal standing waves. But how those waves move within the cavity, and how they interact with the cavity walls and/or the outside world is the subject of several years debate on this forum!
Doesn't the standing wave consist of two waves propagating in opposite directions? The standing wave occurs at the stationary point of constructive interference of the two waves. If this is the case then the illustration shows one of the two waves. The other wave is in the opposite direction but are they necessarily equal? No, there are always losses on the bounce defined in a roundabout way by the quality factor. One of the waves has always bounced more than the other except when the antenna is exactly centered on the node of the standing wave. But of course, it can't be centered on all three nodes. That brings us right back to the differential internal radiation pressure within the frustum. Quantum particles were introduced because the differential radiation pressure argument was dismissed. Quantum particles are judged to have more mass and lower velocity than light waves, hence more thrust for the same energy. But it is not at all clear that the radiation pressure of the light wave is the mechanism coupling the microwave to the quantum particles. If that is so, then the fact that the quantum particles do not reflect from the copper walls gives the resulting momentum reaction to the frustum, thrust in other words. If radiation pressure is not the coupling mechanism then there is yet another mystery, what is the coupling mechanism? Well, this whole EM Drive is a mystery so what's one more mystery added to the soup? -
#84 by Peter Lauwer on 02 Jul, 2018 12:03
-
Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
Hi,
What do you call a "quantum particle"? (I would say all particles are quantum particles)
Apart from that:
1) the EmDrive may not work at all,
2) If it does work, there is no consensus about how/why it should work,
3) If such an explanation is a bit like you draw it here, it is in conflict with conservation of momentum (and would therefore need quite some extra explanation).
Peter -
#85 by scienceguy on 02 Jul, 2018 15:54
-
By "quantum particle" I meant a particle that is created briefly and then annihilated in the quantum vacuum. You're right, I should have been more specific.
-
#86 by zen-in on 02 Jul, 2018 16:28
-
The joint of different metals and its contact potential is only of interest for different temperatures between the contact points because of the Seebeck effect.I'm up to browser bookmark 414 in this blog. I really need a criteria to enable me to get on with my life!
If The Traveller can't make this work, nobody can: he does seem to have a hotline to Shawyer, and talks a decent game on RF engineering, though I suppose metalwork skills (as above) etc are not a given.
I will try and make myself quit worrying if there is nothing forthcoming from TT this year, or on another announced schedule.
I would regard a positive result from Monomorphic as equally definitive in the opposite direction.
So no pressure....
Hi Rert,
Still waiting for the Silver Epoxy. Seems the supplier had no stock when I ordered. Don't want to clean the edge and outer surface before I have the epoxy and then have it start to oxidize.
As for forming over the flower pot, some of the hoop ring are installed internally, help in position with hot glue, to make the form much stiffer. Then more hoop rings are used externally to form and hold the copper frustum in place. Have done this before, so know it can be done fairly easily. The hoop rings are the trick.
Between that I have installed new side and back fencing plus rebuilding bedroom furniture for a friends son. So no rest.
You don't have to worry about Copper oxidation. Copper oxidizes very slowly at room temperature, in dry air. Conductive epoxy contains Silver and will produce a contact potential with Copper. Another method you might want to look into is to use Copper rivets.
To use copper rivets would lead to high conductive but located contact points and do not fit to TT's ( &"Roger's") definition of a good cavity since he states that even small scratches (some µm depth) will lower the Q of the cavity to much.
https://forum.nasaspaceflight.com/index.php?topic=42978.msg1719903#msg1719903
However it is possible to weld the copper wall. I think an expert for such a welding process would be necessary to make the seam, but it is feasible.
A weld seam could be abraded and polished adequately.
Picture source:
https://www.kupferinstitut.de/fileadmin/user_upload/kupferinstitut.de/de/Documents/Shop/Verlag/Downloads/Verarbeitung/i012.pdf
Sorry the text is written in german language but i am sure you will find something similar in english when you search for.
Another method would be to use a bead roller on each edge and then crimp the beads together. If you started with a flat sheet of Copper cut to size and with 3/4" - 1" excess on each end, the firs step would be to roll it into a cone, by setting a roller so it has more pressure on one side than the other. Then roll beads at each end that will lock together and roll them flat. These steps are done every day by HVAC sheet metal specialists. -
#87 by Jim Davis on 02 Jul, 2018 16:29
-
By "quantum particle" I meant a particle that is created briefly and then annihilated in the quantum vacuum. You're right, I should have been more specific.
Isn't "virtual particle" the accepted nomenclature in that case? Or am I misremembering? -
#88 by OnlyMe on 02 Jul, 2018 16:32
-
Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
Nobody has a generally accepted theory of how an EmDrive actually would work at the physical level. However, one thing I think I can say that most if not all will agree on, is that the wave interaction would look nothing like that - it is WAY WAY more complex. The systems are sized to produce standing waves at resonant frequencies within the cavity. The TE013 mode which is the predominant system people are trying essentially produces 3 stacked toroidal standing waves. But how those waves move within the cavity, and how they interact with the cavity walls and/or the outside world is the subject of several years debate on this forum!
Doesn't the standing wave consist of two waves propagating in opposite directions? The standing wave occurs at the stationary point of constructive interference of the two waves. If this is the case then the illustration shows one of the two waves. The other wave is in the opposite direction but are they necessarily equal? No, there are always losses on the bounce defined in a roundabout way by the quality factor. One of the waves has always bounced more than the other except when the antenna is exactly centered on the node of the standing wave. But of course, it can't be centered on all three nodes. That brings us right back to the differential internal radiation pressure within the frustum. Quantum particles were introduced because the differential radiation pressure argument was dismissed. Quantum particles are judged to have more mass and lower velocity than light waves, hence more thrust for the same energy. But it is not at all clear that the radiation pressure of the light wave is the mechanism coupling the microwave to the quantum particles. If that is so, then the fact that the quantum particles do not reflect from the copper walls gives the resulting momentum reaction to the frustum, thrust in other words. If radiation pressure is not the coupling mechanism then there is yet another mystery, what is the coupling mechanism? Well, this whole EM Drive is a mystery so what's one more mystery added to the soup?
The radiation pressure argument/model, whether addressed as bouncing photons or electromagnetic waves, has been addressed repeatedly in the past. In each case the net force should wind up zero... no net asymmetric force or acceleration. Even while there are continuing attempts to revive the basic idea, probably because it would seem “a simple” way to reconcile the conservation of momentum/energy issue... Still it seems a beaten into the ground approach...
That said, should anyone conclusively demonstrate any anomalous force/acceleration associated with the operation of an EmDrive, the anomalous force/acceleration must.., would seem to be derived from an interaction between the frustum itself and the asymmetry of the “standing waves” introduced/generated within the frustum, which would mean that any acceleration would be relative to the frame of reference of the asymmetric electromagnetic magnetic field(s) within the frustum. If this turns out to be the case it would require a reevaluation of just how we interpret some conservation laws. Conservation of momentum becoming less important than conservation of energy... and it would seem unlikely that one could expect an unlimited constant force/acceleration from a constant and unvarying energy input.
Just how any interaction between the frustum and the contained asymmetric electromagnetic field(s) within might generate an anomalous force/acceleration remains an unknown. However, it seems far easier to imagine that some interaction between the asymmetric distribution of the toroidal electromagnetic fields within the frustum and the induced electric currents and corresponding electromagnetic fields in the frustum walls, might generate some small asymmetric anomalous force, even acceleration of the frustum... If an interaction along this line were found to be the source of thrust/acceleration, is would be directly proportional to the intensity of the asymmetric electromagnetic filed(s) and corresponding/resulting electric and magnetic properties induced in the frustum walls... and ultimately the total power/magnitude of the electromagnetic energy introduced into the frustum.
One last point, at this time it does not seem that anyone has published accurate design parameters together with conclusive evidence of successful generation of useable thrust, which leaves most of the DIY and other known experimenters, still searching for the best or proper design.., or holding critical information to theirselves.
P.S. the above was only intended to present the possibility of a more or less classical explanation for a successful EmDrive generating thrust. There are and have been several other models presented in the past, involving interactions with the quantum vacuum, manipulation of inertia and or gravitation and probably others. Though, personally I am skeptical about the manipulation inertia/gravity, I have seen past research arguing that there is an electromagnetic contribution to frame-dragging, which could be extended to linear frame dragging and used as an argument supporting the idea that an EmDrive or similar device might affect the local curvature of “spacetime” and result in some small acceleration, as seen from an outside observer.... A long stretch... The quantum vacuum involvement even a further stretch since the vacuum itself remains highly theoretical at present and any supporting experimental evidence requires far high energies than involved in any published EmDrive experiments.
-
#89 by X_RaY on 02 Jul, 2018 19:12
-
Everyone who has been here for a long time probably knows videos like this... looks fast and relatively easy**
The joint of different metals and its contact potential is only of interest for different temperatures between the contact points because of the Seebeck effect.I'm up to browser bookmark 414 in this blog. I really need a criteria to enable me to get on with my life!
If The Traveller can't make this work, nobody can: he does seem to have a hotline to Shawyer, and talks a decent game on RF engineering, though I suppose metalwork skills (as above) etc are not a given.
I will try and make myself quit worrying if there is nothing forthcoming from TT this year, or on another announced schedule.
I would regard a positive result from Monomorphic as equally definitive in the opposite direction.
So no pressure....
Hi Rert,
Still waiting for the Silver Epoxy. Seems the supplier had no stock when I ordered. Don't want to clean the edge and outer surface before I have the epoxy and then have it start to oxidize.
As for forming over the flower pot, some of the hoop ring are installed internally, help in position with hot glue, to make the form much stiffer. Then more hoop rings are used externally to form and hold the copper frustum in place. Have done this before, so know it can be done fairly easily. The hoop rings are the trick.
Between that I have installed new side and back fencing plus rebuilding bedroom furniture for a friends son. So no rest.
You don't have to worry about Copper oxidation. Copper oxidizes very slowly at room temperature, in dry air. Conductive epoxy contains Silver and will produce a contact potential with Copper. Another method you might want to look into is to use Copper rivets.
To use copper rivets would lead to high conductive but located contact points and do not fit to TT's ( &"Roger's") definition of a good cavity since he states that even small scratches (some µm depth) will lower the Q of the cavity to much.
https://forum.nasaspaceflight.com/index.php?topic=42978.msg1719903#msg1719903
However it is possible to weld the copper wall. I think an expert for such a welding process would be necessary to make the seam, but it is feasible.
A weld seam could be abraded and polished adequately.
Picture source:
https://www.kupferinstitut.de/fileadmin/user_upload/kupferinstitut.de/de/Documents/Shop/Verlag/Downloads/Verarbeitung/i012.pdf
Sorry the text is written in german language but i am sure you will find something similar in english when you search for.
Another method would be to use a bead roller on each edge and then crimp the beads together. If you started with a flat sheet of Copper cut to size and with 3/4" - 1" excess on each end, the firs step would be to roll it into a cone, by setting a roller so it has more pressure on one side than the other. Then roll beads at each end that will lock together and roll them flat. These steps are done every day by HVAC sheet metal specialists.
**with knowledge, experience and the right equipment
-
#90 by scienceguy on 05 Jul, 2018 15:56
-
Hi,
What do you call a "quantum particle"? (I would say all particles are quantum particles)
Apart from that:
1) the EmDrive may not work at all,
2) If it does work, there is no consensus about how/why it should work,
3) If such an explanation is a bit like you draw it here, it is in conflict with conservation of momentum (and would therefore need quite some extra explanation).
Peter
Just out of curiosity, how would that explanation conflict with conservation of momentum? After the virtual particle transfers momentum to the microwave, it disappears. Or does momentum need to be conserved in the vacuum as well? -
#91 by OnlyMe on 05 Jul, 2018 17:13
-
Hi,
What do you call a "quantum particle"? (I would say all particles are quantum particles)
Apart from that:
1) the EmDrive may not work at all,
2) If it does work, there is no consensus about how/why it should work,
3) If such an explanation is a bit like you draw it here, it is in conflict with conservation of momentum (and would therefore need quite some extra explanation).
Peter
Just out of curiosity, how would that explanation conflict with conservation of momentum? After the virtual particle transfers momentum to the microwave, it disappears. Or does momentum need to be conserved in the vacuum as well?
In your earlier hypothetical ...Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. ...?
... and that, in that post you agree “quantum particle” should have been “virtual particle”, ... as far as I can remember no one has presented a convincing argument where the net force or momentum transferred to the frustum would be any different than bouncing photons or waves around the inside of the frustum. There should still be a net null asymmetric force (IOW no net force or acceleration). Any gain a photon might acquire interacting with a virtual particle should still wind up transferring momentum to the walls of the frustum in an overall symmetrical manner. The photons, waves still bounce off all interior surfaces, in the same way they would had they not interacted with virtual particles.
In any case, for the most part the conservation of momentum issue revolves around the issue that if an EmDrive does accelerate, it does so without exchanging any momentum with an external mass or even known field... the acceleration would seam to occur from a completely internally contained process.
Dr. White’s quantum vacuum model attempts to get around this by essentially arguing that the EmDrive is interacting with the quantum vacuum as a whole (inside and outside the frustum so to speak). And there have been a few attempts past and present that attempt to argue that the EmDrive can locally change the shape of spacetime (use gravity) or alter the intial charteristics of the drive in a manner that results in an acceleration as viewed by an outside observer.
But until someone provides a truly functional drive to work with, theory of operation remains largely dependent on imagination.
-
#92 by meberbs on 05 Jul, 2018 17:24
-
Answered your own question. If momentum disappears, then it is not conserved.Hi,
What do you call a "quantum particle"? (I would say all particles are quantum particles)
Apart from that:
1) the EmDrive may not work at all,
2) If it does work, there is no consensus about how/why it should work,
3) If such an explanation is a bit like you draw it here, it is in conflict with conservation of momentum (and would therefore need quite some extra explanation).
Peter
Just out of curiosity, how would that explanation conflict with conservation of momentum? After the virtual particle transfers momentum to the microwave, it disappears. Or does momentum need to be conserved in the vacuum as well?
Noether's theorem on conservation laws applies everywhere. -
#93 by scienceguy on 05 Jul, 2018 17:27
-
what about if the virtual particle moves a little while transferring momentum to the microwave? Maybe while it transfers momentum to the left to the microwave, it moves to the right for a tiny distance, conserving momentum, THEN it disappears.
-
#94 by meberbs on 05 Jul, 2018 17:42
-
what about if the virtual particle moves a little while transferring momentum to the microwave? Maybe while it transfers momentum to the left to the microwave, it moves to the right for a tiny distance, conserving momentum, THEN it disappears.
No, to conserve momentum, it has to transfer the momentum to something else before it disappears. When it does so, it by definition cancels out the momentum that it transferred to the photon. This is no different than the photons just bouncing around transferring momentum on their own, and does not lead to net motion. -
#95 by OnlyMe on 06 Jul, 2018 15:17
-
what about if the virtual particle moves a little while transferring momentum to the microwave? Maybe while it transfers momentum to the left to the microwave, it moves to the right for a tiny distance, conserving momentum, THEN it disappears.
No, to conserve momentum, it has to transfer the momentum to something else before it disappears. When it does so, it by definition cancels out the momentum that it transferred to the photon. This is no different than the photons just bouncing around transferring momentum on their own, and does not lead to net motion.
There is a great deal of theoretical stuff and “if’s” involved in this whole line of discussion but,...
If one first accepts that virtual particles can be created within an EmDrive, any interaction of those virtual particles with photons, electromagnetic waves or even real particles within the frustum, May transfer some momentum in the process. From there it would seem that momentum could still be conserved, in that the virtual particle would be losing momentum in that transfer... the disappearing virtual particle would have a lower “energy, momentum or perhaps even mass” than it did when first created... and we would be essentially extracting energy/momentum from the vacuum, without violating conservation laws.
I don’t believe this is what is happening and the whole quantum vacuum interaction seems a difficult stretch, for too many reasons to get into in a discussion here. That said.., again, if one accepts the existence of a quantum vacuum with characteristics that allow interaction with conventional classical physical systems, we cannot reject out of hand the possibility that a transfer of momentum between components of the quantum vacuum and physical systems is possible. It could even be argued that Unruh radiation may be an example of an exchange of momentum/energy between the quantum vacuum and an accelerating physical object... once more a far more complex discussion than warranted here.
My point is that most of our understanding of and rules dealing with conservation of energy and momentum are tied to conventional classical physical systems, while much of the discussion begins to explore conditions that may not be fully defined as a classical physical system. We don’t really know how conservation laws fit with any interaction between a physical system and the “quantum vacuum”, when we can’t even reach a consensus as to the existence and characteristics of the quantum vacuum.
And to beat a dead horse, I don’t personally believe an interaction with virtual particles is at play here, or that radiation pressure of any sort leads to any anomalous force/acceleration... I do remain hopefully optimistic that these experiments will reveal even a small useable thrust/acceleration. -
#96 by aero on 06 Jul, 2018 17:01
-
The question of course is, "Is there thrust?"
If so,
"Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.
Read more at: https://www.brainyquote.com/quotes/arthur_conan_doyle_134512" -
#97 by LowerAtmosphere on 07 Jul, 2018 12:47
-
The quantum vacuum involvement even a further stretch since the vacuum itself remains highly theoretical at present and any supporting experimental evidence requires far high energies than involved in any published EmDrive experiments.Hey so I've been leisurely skimming these threads for quite some time and I want to know if I understand this EM drive correctly. The microwaves bounce of the walls and then bounce off a quantum particle and back to the wall, imparting momentum. Please see attached diagram. Is this correct?
Nobody has a generally accepted theory of how an EmDrive actually would work at the physical level. However, one thing I think I can say that most if not all will agree on, is that the wave interaction would look nothing like that - it is WAY WAY more complex. The systems are sized to produce standing waves at resonant frequencies within the cavity. The TE013 mode which is the predominant system people are trying essentially produces 3 stacked toroidal standing waves. But how those waves move within the cavity, and how they interact with the cavity walls and/or the outside world is the subject of several years debate on this forum!
Doesn't the standing wave consist of two waves propagating in opposite directions? The standing wave occurs at the stationary point of constructive interference of the two waves. If this is the case then the illustration shows one of the two waves. The other wave is in the opposite direction but are they necessarily equal? No, there are always losses on the bounce defined in a roundabout way by the quality factor. One of the waves has always bounced more than the other except when the antenna is exactly centered on the node of the standing wave. But of course, it can't be centered on all three nodes. That brings us right back to the differential internal radiation pressure within the frustum. Quantum particles were introduced because the differential radiation pressure argument was dismissed. Quantum particles are judged to have more mass and lower velocity than light waves, hence more thrust for the same energy. But it is not at all clear that the radiation pressure of the light wave is the mechanism coupling the microwave to the quantum particles. If that is so, then the fact that the quantum particles do not reflect from the copper walls gives the resulting momentum reaction to the frustum, thrust in other words. If radiation pressure is not the coupling mechanism then there is yet another mystery, what is the coupling mechanism? Well, this whole EM Drive is a mystery so what's one more mystery added to the soup?
The radiation pressure argument/model, whether addressed as bouncing photons or electromagnetic waves, has been addressed repeatedly in the past. In each case the net force should wind up zero... no net asymmetric force or acceleration. Even while there are continuing attempts to revive the basic idea, probably because it would seem “a simple” way to reconcile the conservation of momentum/energy issue... Still it seems a beaten into the ground approach...
That said, should anyone conclusively demonstrate any anomalous force/acceleration associated with the operation of an EmDrive, the anomalous force/acceleration must.., would seem to be derived from an interaction between the frustum itself and the asymmetry of the “standing waves” introduced/generated within the frustum, which would mean that any acceleration would be relative to the frame of reference of the asymmetric electromagnetic magnetic field(s) within the frustum. If this turns out to be the case it would require a reevaluation of just how we interpret some conservation laws. Conservation of momentum becoming less important than conservation of energy... and it would seem unlikely that one could expect an unlimited constant force/acceleration from a constant and unvarying energy input.
Just how any interaction between the frustum and the contained asymmetric electromagnetic field(s) within might generate an anomalous force/acceleration remains an unknown. However, it seems far easier to imagine that some interaction between the asymmetric distribution of the toroidal electromagnetic fields within the frustum and the induced electric currents and corresponding electromagnetic fields in the frustum walls, might generate some small asymmetric anomalous force, even acceleration of the frustum... If an interaction along this line were found to be the source of thrust/acceleration, is would be directly proportional to the intensity of the asymmetric electromagnetic filed(s) and corresponding/resulting electric and magnetic properties induced in the frustum walls... and ultimately the total power/magnitude of the electromagnetic energy introduced into the frustum.
... The quantum vacuum involvement even a further stretch since the vacuum itself remains highly theoretical at present and any supporting experimental evidence requires far high energies than involved in any published EmDrive experiments.
Your points about side wall interaction and the layering of the field are correct and your post is very useful but the energy density argument is WRONG. I have repeatedly proven in prior posts that the peak field density along the central modal points is above vacuum permittivity!!!! I will share my old posts again to clarify this point.
My old post #1 regarding repeated CoM bias:
would you agree that stimulated emissions from a laser or spaser exceed the activation energy? Would you agree that the hamiltonian for a system is unrelated to the specific charge imbalance/stress tensors or rather the magnetic dipoles which occur in a metal can cause the electrons to break the non-crossing condition if the refractive index is different (among other reasons such as the entire Octupole/Quadrupole discussion)? Do you recognize that anisotropic effects throughout a cold plasma and or resonant phonons can transmit force without equivalent input energy? Then you will see that OU is nonsense in the context of intra-cavity reactions. CoE and CoM is a dead end I have said it before and I will say it again.
----------
07/02/2017
Hyperplanck's posts about phonons fit perfectly into this.
@Monomorphic, yes I was referring to some spherical/parabolic end simulations. Since proposing the hypothesis here - credit to Flux_Capacitor for being the first to notice that the field strength was high enough for dielectric breakdown and for proposing the white noise injection via klystron in thread 8, as we now recently discovered that the system will store a wide bandwidth.
2.4x10^7kV/m was quoted in my previous posts, so I assumed this was a modal peak value from one of the simulations. I did some extensive digging through the past two threads and found some examples of both realistic and futuristic peak values which I included below. As expected, parabolic mirrors or spherical ends work best at creating a focal point for maximum density, though the modal shape is usually something symmetric along the wrong axis* or a TM sidewall pressure (versus endcap pressure) which decreases thrust because the resonant wave's information caught in the plasma/ions/wavelets/phonons/electron soup (take your pick) has a more similar time-to-wall. There is a lesser pressure gradient in a desirable direction if your field is symmetric across the perpendicular of your acceleration vector or if it is symmetric and each peak is equally strong. Most simulated peak fields are around 700kV/m, which is not close enough to the 3000kV/m (or ~3300kV/m) to appear to matter. There is natural ambient ionization in the air which is increased once you begin injecting large amounts of energy into the cavity*** even if the ionization cycle does not begin for hot plasma, like you would see in a tokomak**. The behaviour of the plasma depends on the voltage, the geometry, the wave shape, the waveguide and most crucially the eigenmodes.
Max E-Fields Old Simulations
Spherical endplate TE012 - 36MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1610054#msg1610054
TT - 7.5MV/m - https://forum.nasaspaceflight.com/index.php?topic=41732.msg1616337#msg1616337
Cannae - 25.6MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1612540#msg1612540
Sphere - 6.5MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1611016#msg1611016
Tapered prism (Similar to Yang) - 3.017MV/m https://forum.nasaspaceflight.com/index.php?topic=40959.msg1610152#msg1610152
Spherical endplate TE013 - ~27MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1608904#msg1608904
Helical Antenna clover leaf - very high - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1608617#msg1608617
I think the old posts by Dr. Rodal regarding fluid mechanics are also interesting and worth considering though they rely on the exchange of kinetic energy of massive particles, not electron pressure between current layers(=standing waves) and therefore do not solve CoM issues as they are not directional unlike field line relaxations.
* For example: TE011 where both endcaps more or less share the same central field (or only a few 'layers of the onion' when compared to TE013 or TE019). The layers cause the lag in information through magnetic reconnection, while the location of the modal peak determines the source of the information.
**All this rephrases my previous posts a bit and makes a lot more sense after you read Yamada's 2010 guide to magnetic reconnection. The theory is that the reconnection rate scales with how collisionless the plasma is as a function of the mean free path of the electron and furthermore strong guide fields slow down the reconnection rate. If you have a fairly weak system like the EM Drive then you either need: a long distance to build charge needed for realignment (like the Earth's cold magnetotail) or boundary conditions which keep the pressure locked in and the waves resonate along more or less closed paths. I cannot hope to explain the entire concept better than Yamada did so read his guide and mentally add in the recent discoveries about fast reconnection, relativistic electrons, electron behaviour in metallic lattices, plasmonics, and phonons. If we even achieve 1% ionization equilibrium (assuming only the atmosphere matters) then you will be getting thrust. If you achieve 99% ionization then you will need strong guide fields to prevent turbulence which in turn reduces reconnections. The golden zone is somewhere in the middle where the cold plasma does not pose a danger when unstable. All of this is some late night thoughts so apologies for typos...
***Among others, it is clear since the 1970s that in their excited state many of the elements in air will disassociate. If you keep injecting energy, more of the electrons will be excited on average. https://www.nist.gov/publications/ionization-carbon-nitrogen-and-oxygen-electron-impact-0
-
#98 by Monomorphic on 07 Jul, 2018 15:33
-
Max E-Fields Old Simulations
Spherical endplate TE012 - 36MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1610054#msg1610054
TT - 7.5MV/m - https://forum.nasaspaceflight.com/index.php?topic=41732.msg1616337#msg1616337
Cannae - 25.6MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1612540#msg1612540
Sphere - 6.5MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1611016#msg1611016
Tapered prism (Similar to Yang) - 3.017MV/m https://forum.nasaspaceflight.com/index.php?topic=40959.msg1610152#msg1610152
Spherical endplate TE013 - ~27MV/m - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1608904#msg1608904
Helical Antenna clover leaf - very high - https://forum.nasaspaceflight.com/index.php?topic=40959.msg1608617#msg1608617
As you pointed out, these are older simulations, and as such they are not entirely accurate. TT's and a couple of others for example were simulated at 1,000W, instead of the usual 30W I run the simulations at now (since that is the power of my amplifier). The helical antenna very high reading I think was a bug with the software as when I closed it down and opened it the next day, that was not a repeatable result. Others were run with what amounts to a perfect conductor instead of copper, which makes a huge difference.
It would probably be best to rerun all of those simulations under the same conditions. As an example, the spherical end-plate cavity when rerun under normal conditions (copper walls and 30W), tops out around 150kV/m. Between 100kV/m and 200kV/m seems to be about the typical I would be able to get using the current amplifier and coupler setup.
-
#99 by OnlyMe on 07 Jul, 2018 18:14
-
....
The quantum vacuum involvement even a further stretch since the vacuum itself remains highly theoretical at present and any supporting experimental evidence requires far high energies than involved in any published EmDrive experiments.
Your points about side wall interaction and the layering of the field are correct and your post is very useful but the energy density argument is WRONG. I have repeatedly proven in prior posts that the peak field density along the central modal points is above vacuum permittivity!!!! I will share my old posts again to clarify this point.
...
Your argument seems to me one of apples and oranges.
First, though I believe the existence of the quantum vacuum (QV) is generally accepted, the exact composition of the QV and its potential interaction with “ordinary” matter remains theoretical and hotly debatable.
Second, any attempt to compare any localized field intensity with the energy required to create a massive particle., even a short lived massive virtual particle, is more speculation than even a theoretical predictions of QFT/QED.
Consider that the energy content of one proton would be 938.257 MeV and that so far the highest powered experiments have employed magnetrons... assume a 1000 watt magnetron and 100% of that energy reaching the field within the frustum... 1kWh= 2.246943e+25eV which leaves a significant gap and assumes the magnetron was transmitting for a full hour, not seconds or even minutes. Just not enough energy is added to the system to create massive particles for even short periods of time.
Is it possible that a resonant microwave field within a frustum alters how the physical structure of the EmDrive might interact with the QV? Sure but that is something yet to be proven and depends on just how we describe the fundament characteristics of the QV...
Beyond that I was referring to what little we know from experimental data, opposed to the theoretical implications of simulations. Again, what is really needed is to pin down a functional design, that generates reproducible results. Even while simulations have and will continue to be useful tools, the proof will be in the data generated from experiment.
