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#1580 by Eusa on 24 Apr, 2016 21:49
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I cannot see anything in nature that some quantum vacuum energy could come from space itself. No, the zero point energy keeps its zero. Only way is to accelerate other bodies of the heaven and get thereby some reaction.
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#1581 by meekGee on 24 Apr, 2016 22:05
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...
That's the kind of thing I'm looking for, but would that violate conservation of energy?
IIUC, the EM drive eats energy and produces thrust, just like any rocket. Rocket lose a lot of energy into the propellant, and in that respect, an EM drive will have some "specific impulse".
Unless I'm missing something, this apparatus will only violate conservation of energy if the generator makes more energy than is put into the EM drive...
Correct. Professor Frobnicat was the first one to show that, if the claims that the EM Drive can produce a force/PowerInput greater than the one of a photon rocket (Prof.Yang claims that in her experiments she produced over 300,000 times the Force/PowerInput of a photon rocket) then at a given speed, the kinetic energy exceeds the energy input and hence excess power is produced, therefore violating conservation of energy. Most EM Drive proponents (i.e. Shawyer, Yang, etc.) put this "under the carpet". Dr. McCulloch deals with it full-front and admits that according to his Unruh effect theory this is possible, and he claims that the excess-energy would come from the Quantum Vacuum.
ok (and again apologies for most likely rehashing old territory)
So a photon rocket conserved momentum since the photons clearly carry momentum, and has an awful power efficiency, just like any very high ISP rocket.
Any rocket using "lower velocity exhaust" will have better power power efficiency, and lower ISP. So the 300,000x factor is not surprising (so far...)
With the EM drive OTOH, we can't identify the "exhaust". But let's assume, that just like a car on tires, there's no exhaust. There's simply a momentum exchange with the rest of the universe, through the mechanism of magic.
If that's the case, then you don't need to break conservation of energy. You produce an impulse to the left, and the rest of the universe moves to the right. How? funky physics magic. But nothing was broken - it's just that the ship is not an isolated system.
So let's assume we're trying to make a free energy generator, in order to prove that the EM drive can't be built.
Let's make it one dimensional - one EM carriage is moving left-to-right, the other is moving right-to-left, and the generator operates between them. Because of symmetry, it no longer matters that the EM carriages somehow connect to the rest of the universe, since they cancel each other. They might as well be pushing against each other - which can be achieved with any mechanical means.
So you don't need any photon rocket limits. You put a certain amount of energy into the drives, they move in their opposite directions, and you collect the energy from the generator.
Free energy would mean you get more energy out of the generator than you put into the drives, but that's not implied in anything about the EM drive so far, again IIUC - unless I am missing the point about the photon rocket. -
#1582 by Monomorphic on 24 Apr, 2016 23:05
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Sims of the wedge geometry i'm working on. I'm not sure if anyone has shown Phi rotate before. I think it helps visualize the fields.
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#1583 by RotoSequence on 24 Apr, 2016 23:10
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Sims of the wedge geometry i'm working on. I'm not sure if anyone has shown Phi rotate before. I think it helps visualize the fields.
Very interesting... I'm particularly curious to see what kind of results TE012 and TE014 give. -
#1584 by tleach on 24 Apr, 2016 23:13
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Gave that a go. On the left, no dialectric. On the right, five layers of dialectrics. Top layer (layer1) relative elec perm=3, layer2=2.25, layer3=1.5, layer4=0.75, layer5=0.01 I also used flaring, like the bell of a trumpet, for the side walls.
Thanks for trying out the scalar horn frustum (trumpet bell) shape! It looks like it can resonate at least as well as a traditional frustum shape, at least it can if you don't start putting in too many dielectric layers :-) -
#1585 by Tellmeagain on 25 Apr, 2016 00:04
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Professor Higgins also said that in his paper, that for energy to be conserved, force/power can not exceed that of photon rocket. His paper is at arXiv, http://arxiv.org/pdf/1506.00494.pdf
...
That's the kind of thing I'm looking for, but would that violate conservation of energy?
IIUC, the EM drive eats energy and produces thrust, just like any rocket. Rocket lose a lot of energy into the propellant, and in that respect, an EM drive will have some "specific impulse".
Unless I'm missing something, this apparatus will only violate conservation of energy if the generator makes more energy than is put into the EM drive...
Correct. Professor Frobnicat was the first one to show that, if the claims that the EM Drive can produce a force/PowerInput greater than the one of a photon rocket (Prof.Yang claims that in her experiments she produced over 300,000 times the Force/PowerInput of a photon rocket) then at a given speed, the kinetic energy exceeds the energy input and hence excess power is produced, therefore violating conservation of energy. Most EM Drive proponents (i.e. Shawyer, Yang, etc.) put this "under the carpet". Dr. McCulloch deals with it full-front and admits that according to his Unruh effect theory this is possible, and he claims that the excess-energy would come from the Quantum Vacuum. -
#1586 by frobnicat on 25 Apr, 2016 00:11
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...
That's the kind of thing I'm looking for, but would that violate conservation of energy?
IIUC, the EM drive eats energy and produces thrust, just like any rocket. Rocket lose a lot of energy into the propellant, and in that respect, an EM drive will have some "specific impulse".
Unless I'm missing something, this apparatus will only violate conservation of energy if the generator makes more energy than is put into the EM drive...
Correct. Professor Frobnicat was the first one to show that, if the claims that the EM Drive can produce a force/PowerInput greater than the one of a photon rocket (Prof.Yang claims that in her experiments she produced over 300,000 times the Force/PowerInput of a photon rocket) then at a given speed, the kinetic energy exceeds the energy input and hence excess power is produced, therefore violating conservation of energy. Most EM Drive proponents (i.e. Shawyer, Yang, etc.) put this "under the carpet". Dr. McCulloch deals with it full-front and admits that according to his Unruh effect theory this is possible, and he claims that the excess-energy would come from the Quantum Vacuum.
Thanks dr Rodal for taking great consideration for my previous (anonymous public forum posts only) work on the subject and keeping those conclusions afloat. Just a little precision, while I'm certainly an early popularizer of the 1st principle issues of EM drive since this thread series got momentum in 2014 (following Brady et al. report from EagleWorks), and I'm reasonably proud of that and of the "constant velocity" turn I gave on it (as a more personal contribution), I am aware of at least half a dozen people "out there" having made similar (and sometimes as well if not better formulated) remarks, for propellantless schemes in general, before my own posts (and including the constant velocity wheel idea in some instances). Will have to do a short list of links at some time... (right now its just forgotten from browsing history cache)... Well as I said, it seems a rather straightforward consequence and not likely to be forgotten, more likely to be "rediscovered" again and again, also raging recently on Woodward's effect thread.
@meekGee :
when talking about "propellantless schemes in a real vacuum" I'm excluding things that push/drag on real matter or field that do define a natural rest frame and hence a natural efficiency=function(velocity_relative_to_real_medium), like solar sailing, electrodynamic tethers... It is not excluded that EM drive effect, if it is confirmed (which I doubt), is indeed coupling with such a real field or dark flow of some sort that do define a natural rest frame relative to which the efficiency (Force per power input) varies in such a way as to save the apparence of energy conservation (as is the case for powered electrodynamic tethers in "motor mode" for instance), and simultaneously ruins the hopes for a complete revolution of propulsion in deep space from EM drive as the problem for fast space travel is not so much one of momentum but one of energy (as is evidenced by the rather energy starved than propellant mass starved high specific impulse ion drives propelled missions for instance, at least for fully autonomously powered propulsion, ie. far from the sun, requiring nuclear power fuel densities).
With this restriction in mind, that I'm talking of a fully relativistic effect (with no preferred rest frame, which as far as I know is the leading expectation among the proponents, as none as ever provided experimental test about velocity relative to likely natural rest frames apart from "the ground" which is irrelevant for deep space, nor discussed that theoretically) the whole point of EM drive effect and more generally of "relativistic propellantless schemes in a real vacuum" is precisely that the "generator makes more energy than is put into the EM drive" Because if it wasn't able of such a feat then it wouldn't be more interesting than a photon rocket at 3.33µN/kW. A steady state "propellantless thruster" (by definition not bleeding mass, at least no other than the extremely tiny amount of mass equivalent to the spent onboard energy/c˛, whether radiated or lost otherwise) simply has to be able to generate more energy than it consumes (in specific conditions) to be able to beat a photon rocket. It can also "dissipate" (literally make vanish) more energy than it radiates (in other specific conditions, but that's another story). For quantitative argument around you can see for instance those 2 posts (I'm linking to my own posts not because of self promotion agenda but because I can answer to that content)
https://forum.nasaspaceflight.com/index.php?topic=39772.msg1512120#msg1512120
https://forum.nasaspaceflight.com/index.php?topic=39004.msg1461319#msg1461319
Recall that to compare a rocket with a propellantless scheme, to be fair and compare apples to apples or oranges to oranges, one has to convert apple to oranges as per E=mc˛. The mass flow of the exhaust of a classical action/reaction rocket, even a very high specific impulse one, when converted (considered) as an energy flow, makes the power used to accelerate the propellant mass relative to the spacecraft pale in comparison. In this sense the spent power (all included) per given thrust of a classical action/reaction rocket is actually higher than that of a photon rocket. It's only because we don't know of a way to transmute dead mass of burnt fuel into energy than we throw overboard all this colossal reserve of energy ( = mc˛ ). The liter of (really) hot water vapor (H20) at the output of a cryogenic engine is worth almost 1017 J or about 20 MegaTon of TNT. 3 liters make (would make) for the equivalent in energy of the most powerful thermonuclear weapon ever detonated, the Tsar Bomba. So in the end, spending mass is spending energy (even if we don't really know how to use it, short of nuclear reactions, and that's still a tiny amount of converted mass), and to compare a classical action/reaction rocket to a photon rocket and to a functional EM drive this is to be taken into account. Seen as a propellantless thruster (counting all that is spent as energy) classical action/reaction is extraordinarily loosy.
The other way around (oranges to apples), a photon rocket that uses an onboard nuclear reactor (or RTG) and transmutes say 1g of mass into energy, assuming 10% efficiency, gets a kick of p=.1*E/c=.1*mc=30000 kg.m/s (a 300kg spacecraft gets a deltaV of 100m/s). A chemical rocket that sacrifice the exact same amount of onboard mass (by burning it chemically and throwing the resulting "ashes" down the nozzle into vacuum) has say a specific impulse of 450s, about 4400 m/s exhaust velocity in vacuum, that makes for a kick of ... p=4.4 kg.m/s. Nothing to laugh at but that's a deltaV of 0.015 m/s for our 300kg spacecraft. On the other hand an EMdrive with a "figure of merit" that's 10000 times more efficient than a photon rocket, i.e. at about 33mN/kW as is routinely (almost casually) discussed here, from 1g of burned nuclear fuel (same generator as above for the photon rocket) will get us a kick of p=10000*.1*E/c=1000*mc=300000000 kg.m/s. Our EM drive powered spacecraft of 300kg will gain a deltaV of 1000km/s (2 times above galactic escape velocity). By burning 1g of nuclear fuel and converting it to electricity with 10% efficiency. A spacecraft of 300kg having for sole compensation of gaining 1000km/s the loss of one gram of mass. I'm not here to troll, the numbers speak by themselves. This drive is not an "engine that converts electric energy to kinetic energy", it's basically a generator that harvests energy from some dark place, and the apparent required energy to power it (microwave RF generator) is only a "catalyst" in trace amounts compared to the dark source, as much as the energy spent by the crew of a sail boat is minute compared to the energy given to the sail boat by the wind. And like automating the principle of a sail into a windmill, it's no surprise that this can be used as a net generator (over-unity feedback) in some appropriate conditions.
BTW since a lot of links provided recently (summarized) by dr Rodal points to Feigel effect (or similar concepts) has this link been already shared here ?
Does the Feigel effect break the first law? Ottavio A. CrozeQuote from: Ottavio A. CrozeThis revised analysis shows that there can be no net vacuum momentum contribution in a steady Feigel effect.
.../...
... either the vacuum does not actually transfer momentum to the ME medium or energy (albeit in tiny amounts) can be extracted from the vacuum without other energy input. This is a blatant violation of conservation of energy the first law of thermodynamics. Similar considerations apply to the vacuum radiometer. The rotation of its magnetoelectric vanes caused by the vacuum would be dissipated by friction at the pivot ...
.../...
The analysis, however, demonstrates quite clearly how a steady Feigel effect should not exist purely on thermodynamic grounds (one cannot extract free momentum or energy from the vacuum).
sorry for the rough cut job, just pointing to the sentences with similar reasoning (other parts of the paper involve technicalities I'm not familiar with), basically that a steady state vacuum actuated "wheel" will get us into free energy territory as soon as net steady state QV momentum contribution is present. Granted, the systems under consideration are not "powered" as they consider static fields, so the energy conservation trouble is all the more evident.
edit in red
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#1587 by Vesc on 25 Apr, 2016 00:51
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In regards to "Prof."[1] Frobnicat's excellent expose on this issue to meekGee (a long time poster to NSF IIRC), I have another question. If the EM Drive *were* acting as a catalytic engine would there be any scenario whereby "constant power in" would not yield a constant force out? Especially in regards to the recent paper by McCullough (sp?). It would be weird to consider inertia to be non-constant, but then again it's weird to consider that relativistic objects increase in mass. I guess I'm hypothesizing that this Unruh 'radiation' would behave differently on a moving object such that the simple formula F = Pin/c no longer holds? And what would be the implications of that that might be considered nonphysical? Thanks in advance for any consideration and observations you can provide....
[1] Since I don't know you personally, or in any other matter outside of this forum, and you are using a pseudonym (as am I, nothing wrong with that) I am going to defer to the authority of Dr. Jose Rodal who has called you such and as since he is a publicly known figure whose credentials I have independently verified to my satisfaction (as good as that is
and with a reputation to protect I'm going to assume he has somehow verified that or he wouldn't be calling you such.
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#1588 by Rodal on 25 Apr, 2016 00:52
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Donaire, van Tiggelen and Rikken, in their 2015 work quote both Croze 2012's work and Feigel's:
BTW since a lot of links provided recently (summarized) by dr Rodal points to Feigel effect (or similar concepts) has this link been already shared here ?
Does the Feigel effect break the first law? Ottavio A. CrozeQuote from: Ottavio A. CrozeThis revised analysis shows that there can be no net vacuum momentum contribution in a steady Feigel effect.
.../...
... either the vacuum does not actually transfer momentum to the ME medium or energy (albeit in tiny amounts) can be extracted from the vacuum without other energy input. This is a blatant violation of conservation of energy the first law of thermodynamics. Similar considerations apply to the vacuum radiometer. The rotation of its magnetoelectric vanes caused by the vacuum would be dissipated by friction at the pivot ...
.../...
The analysis, however, demonstrates quite clearly how a steady Feigel effect should not exist purely on thermodynamic grounds (one cannot extract free momentum or energy from the vacuum).
sorry for the rough cut job, just pointing to the sentences with similar reasoning (other parts of the paper involve technicalities I'm not familiar with), basically that a steady state vacuum actuated "wheel" will get us into free energy territory as soon as net steady state QV momentum contribution is present. Granted, the systems under consideration are not "powered" as they consider static fields, so the energy conservation trouble is all the more evident.
edit in red
Transfer of linear momentum from the quantum vacuum to a magnetochiral molecule
M. Donaire, B.A. van Tiggelen and G.L.J.A. Rikken
http://arxiv.org/pdf/1404.5990.pdf
I have to refresh my mind on how they dealt with the criticism of Feigel' work (I seem to recall that they did at some point in time) or whether they ever addressed Croze's 2013 (which is earlier than their 2015 work).
I see that Croze has a caveat: steady (not allowed), while unsteady (which is allowed).
And I notice that EM Drive experiments up to now have been short-duration (is what they are measuring steady ?)
Also, Croze discusses a "steady Feigel effect". Is a "steady Feigel effect" identical to s a "Donaire, van Tiggelen effect"? -
#1589 by frobnicat on 25 Apr, 2016 00:57
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.../...
With the EM drive OTOH, we can't identify the "exhaust". But let's assume, that just like a car on tires, there's no exhaust. There's simply a momentum exchange with the rest of the universe, through the mechanism of magic.
If that's the case, then you don't need to break conservation of energy. You produce an impulse to the left, and the rest of the universe moves to the right. How? funky physics magic. But nothing was broken - it's just that the ship is not an isolated system.
.../...
Sorry to quote and respond only to this part, no time to dig further, hope my previous post can clarify some other concerns.
So the question is : what is the velocity of the spacecraft relative to the "rest of the universe" upon which it is supposed to push ? What is the velocity of an EM drive sitting in the vacuum chamber at Eagleworks lab relative to this "road" with which it will exchange momentum ? Now ? 11 hours, 58 minutes, and 2 seconds (half a sidereal day) later ? What comes to the axis of thrust relative to this velocity when the device is turned 90° or 180° ?
Because when exchanging momentum with a road, the power needed (or recovered) depends not only on the force but also on the relative velocity of the vehicle with respect to the road, as per spent_power=F.Vel (scalar product between the 2 vectors) and is negative if force is opposite to velocity (as in braking) in which case spent_power is negative, meaning actually some power is harvested (even if it is often dissipated locally as waste heat, it can at least partially be recovered as useful power, as in regenerative breaking). So knowing this relative velocity on what a device is pushing is crucially important to understand its energetic aspects.
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#1590 by meekGee on 25 Apr, 2016 01:33
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Very true..../...
With the EM drive OTOH, we can't identify the "exhaust". But let's assume, that just like a car on tires, there's no exhaust. There's simply a momentum exchange with the rest of the universe, through the mechanism of magic.
If that's the case, then you don't need to break conservation of energy. You produce an impulse to the left, and the rest of the universe moves to the right. How? funky physics magic. But nothing was broken - it's just that the ship is not an isolated system.
.../...
Sorry to quote and respond only to this part, no time to dig further, hope my previous post can clarify some other concerns.
So the question is : what is the velocity of the spacecraft relative to the "rest of the universe" upon which it is supposed to push ? What is the velocity of an EM drive sitting in the vacuum chamber at Eagleworks lab relative to this "road" with which it will exchange momentum ? Now ? 11 hours, 58 minutes, and 2 seconds (half a sidereal day) later ? What comes to the axis of thrust relative to this velocity when the device is turned 90° or 180° ?
Because when exchanging momentum with a road, the power needed (or recovered) depends not only on the force but also on the relative velocity of the vehicle with respect to the road, as per spent_power=F.Vel (scalar product between the 2 vectors) and is negative if force is opposite to velocity (as in braking) in which case spent_power is negative, meaning actually some power is harvested (even if it is often dissipated locally as waste heat, it can at least partially be recovered as useful power, as in regenerative breaking). So knowing this relative velocity on what a device is pushing is crucially important to understand its energetic aspects.
So based on that, can we still say with certainty that if the EM drive gives more thrust/energy thana photon rocket, it violates conservation of energy?
Or does it depend on the magic by which it works?
With a photon rocket, the counter momentum is the relativistic momentum of the photons.
With the EM drive, it can be anything. Maybe it interacts with rest of the universe in a way that depends on the relative velocity between itself and each specific bit of the universe... *
So I don't see an automatic violation of energy principles... Yet.
So still skeptical and unsure... The purist in me is waiting for the clear debunking. The optimist is waiting for more corroboration and unambiguous results...
* EDIT, or it interacts with the rest of the universe in a way that is proportional to 1/r2, so your frame of reference for measuring velocity is just the Earth.... How uninspiring, ironic, and useless for space travel.... -
#1591 by RotoSequence on 25 Apr, 2016 01:41
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<Under-Informed Spitballing>Maybe there is a preferred reference frame for EM drive to rely on, and everything is relative to the origin point of the Big Bang</Under-Informed Spitballing>
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#1592 by Rodal on 25 Apr, 2016 01:59
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...
Donaire, van Tiggelen and Rikken, in their 2015 work quote both Croze 2012's work and Feigel's:
BTW since a lot of links provided recently (summarized) by dr Rodal points to Feigel effect (or similar concepts) has this link been already shared here ?
Does the Feigel effect break the first law? Ottavio A. CrozeQuote from: Ottavio A. CrozeThis revised analysis shows that there can be no net vacuum momentum contribution in a steady Feigel effect.
.../...
... either the vacuum does not actually transfer momentum to the ME medium or energy (albeit in tiny amounts) can be extracted from the vacuum without other energy input. This is a blatant violation of conservation of energy the first law of thermodynamics. Similar considerations apply to the vacuum radiometer. The rotation of its magnetoelectric vanes caused by the vacuum would be dissipated by friction at the pivot ...
.../...
The analysis, however, demonstrates quite clearly how a steady Feigel effect should not exist purely on thermodynamic grounds (one cannot extract free momentum or energy from the vacuum).
sorry for the rough cut job, just pointing to the sentences with similar reasoning (other parts of the paper involve technicalities I'm not familiar with), basically that a steady state vacuum actuated "wheel" will get us into free energy territory as soon as net steady state QV momentum contribution is present. Granted, the systems under consideration are not "powered" as they consider static fields, so the energy conservation trouble is all the more evident.
edit in red
Transfer of linear momentum from the quantum vacuum to a magnetochiral molecule
M. Donaire, B.A. van Tiggelen and G.L.J.A. Rikken
http://arxiv.org/pdf/1404.5990.pdf
I have to refresh my mind on how they dealt with the criticism of Feigel' work (I seem to recall that they did at some point in time) or whether they ever addressed Croze's 2013 (which is earlier than their 2015 work).
I see that Croze has a caveat: steady (not allowed), while unsteady (which is allowed).
And I notice that EM Drive experiments up to now have been short-duration (is what they are measuring steady ?)
Also, Croze discusses a "steady Feigel effect". Is a "steady Feigel effect" identical to s a "Donaire, van Tiggelen effect"?
In this reference van Tiggelen and Rikken differentiate their approach from the Feigel process.
They go over the equations and they propose experiments:
The Feigel Process Process
The Momentum of Quantum Vacuum
Bart van Bart van Tiggelen Tiggelen CNRS -France
http://lpm2c.grenoble.cnrs.fr/UserFiles/File/ESA%20kick-off.pdf -
#1593 by SeeShells on 25 Apr, 2016 03:16
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Some readers might want a refresher. I find that so much is out there in theories that I helps to ground myself every so often.
https://en.wikipedia.org/wiki/Quantum_vacuum_thruster
Shell -
#1594 by X_RaY on 25 Apr, 2016 06:31
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I tried stacked dialectrics with a high electric permittivity. Starting with 30 at the top and ending with 6 at the bottom. RF injection was into the middle at layer with 18 permittivity. Got a result that doesn't look very promising.
What are the dimensions of this this resonator?
Did you take into account that the wavelength in the dielectric depends on both the local wavelength in the metallic cavity and the permittivity?
Please remember the dielectric lowers the natural resonant frequency of each mode
Example :
cylindrical cavity resonator,
2a=100mm
L=100mm
complete "filled" with vacuum eps_r=1
TE012@4,727GHz
whole inner volume with dielectric eps_r=30
TE012@0,863GHz
The difference is equal to the factor sqrt(eps_r).
To get resonance you have to choose the dimensions as well as the permittivity of all single layer very carefull. -
#1595 by Impaler on 25 Apr, 2016 07:51
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Wet blanket theory here from lurker. From last few pages of reading higher thrust was observed with plastic dielectric insert and their is some speculation about this allowing some kind of desirable gas or molecule to enter chamber.
But could the entire thrust measurement simply be the result of sputtering of atoms off the insert in a kind of internal solid rocket motor. It would exhibit the sharp start and stop properties that have suggested thrust is not simply coming from the devices getting hot after extended run times.
If this is correct thrust would always be in the direction having the plastic insert, is that consistent with observations? -
#1596 by OttO on 25 Apr, 2016 08:24
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Would the following paper apply also to microwaves?
http://arxiv.org/abs/1603.07224
Photon mass drag and the momentum of light in a medium
as a direct consequence of the fundamental conservation laws of nature and the special theory of relativity, the energy and momentum of light propagating in a medium are carried by quasiparticles, coupled states of fi eld and matter, which have a finite rest mass and the Minkowski form of momentum...The finite rest mass of the quasiparticle directly leads to a photon mass drag effect optomechanically displacing the medium along the photon flow -
#1597 by RERT on 25 Apr, 2016 08:37
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A couple of things:
1) On a post Dr.Rodal made at or close to the point where he introduced the research on magnetochiral molecules/QV, I couldn't help noticing the scaling "1 nm/s at B=10T" in the picture of a slide. It seems like this would be negligible in any DIY experiment. Happy to be shown wrong, but that's as it appears at first blush.
2) I'm very encouraged by DaChuna's news that TU Dresden is handing out PhD studentships to optimize EM-drive resonances. Sounds like some serious work is going on there.
R. -
#1598 by frobnicat on 25 Apr, 2016 08:44
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<Under-Informed Spitballing>Maybe there is a preferred reference frame for EM drive to rely on, and everything is relative to the origin point of the Big Bang</Under-Informed Spitballing>
There is no "origin point" as there was no space-time in which such point to be placed, but there is something as an average local rest frame, as measured by the frame in which the photons of the CMB are seen neither blue shifted nor red shifted in any particular directions. Earth and its host galaxy are far from being at rest relative to that frame, we are drifting at a few hundreds of km/s relative to it. Also this does make some kind of "absolute" velocity (or energy) limit for charged particles travelling in vacuum : Greisen–Zatsepin–Kuzmin limit. Notice that this limit concerns only relativistic velocities, no time to extrapolate but at 7TeV (LHC at Higgs discovery level) a proton goes "99.9999991% times the speed of light" and Greisen–Zatsepin–Kuzmin limit is for energies 7 orders of magnitude above TeV accelerator.
But this "average" rest frame has no intrinsic physical meaning (in usual treatment of QFT that I'm aware of) for true physical vacuum, and there is no conclusive experimental evidence (that I'm aware of, but this is not my domain) that there is a breaking of relativity for true physical vacuum in absence of such relic radiation. In particular this content (real photons) above the quantum vacuum can't explain an EM-drive effect in a lab as :
1- There is no way that such CMB photons can enter the metallic cavity, i.e. make it inside the drive, and putting all the test apparatus inside a metallic vacuum chamber (Eagleworks experiments) makes it even more impossible for CMB photons to play any role.
2- For low energy photons there is no self interaction of EM radiation with EM radiation.
3- The density of CMB is extremely low, 3.38×10-11Jm-3.
Relic neutrinos will also define an average local rest frame (same as CMB photons ?), and they will traverse through and into metallic cavities, but don't interfere much. And there's not much of a density either. And they are weakly interacting. Dark matter is gravitationally bounded to local lumps (local cluster, galaxy, perhaps even concentrating at stellar level) so defines an other local rest frame than the relic particles. But again gravitational effect upper bounds show densities too low to explain momentum exchange with EM drive effect (but not vanishingly small if assuming strong coupling with... those extremely weakly interacting particles). Other conceivable "ghost" particles or "dark" fields have similar upper bound by the same studies used for dark matter searches, and hence are known to have energy densities a bit short of explaining EM drive effect (by local interactions). This last point would probably deserve more work to be ascertained with certainty I think (taking into account estimates of cross section and flows for given average relative velocities and temperatures).
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#1599 by Rodal on 25 Apr, 2016 13:15
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Hackaday tiny EM Drive V. 4 with ABS polymer insert shows test with cavity reversed ( the cavity is turned in the opposite direction.).. but know what?
It shows reverse direction
Aachen team writes: "test looking good" with ABS polymer insert
results appear better than without polymer insert
https://hackaday.io/project/5596-em-drive/log/36758-test-with-dielectric-cavity-reversed
Hope that they eventually try:
1) polymer insert at small end instead of big end
2) semi-crystalline HDPE extruded insert instead of amorphous spaghetti 3D printed ABS
and with a reputation to protect I'm going to assume he has somehow verified that or he wouldn't be calling you such.
