Author Topic: EM Drive Developments - related to space flight applications - Thread 2  (Read 2098290 times)

Offline Stormbringer

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From what I remember, originally there was the Alcubierre "Warp Drive" concept proposed by Mexican physicist Miguel Alcubierre, which required a jupiter-sized mass of dark matter. Then Dr White came up with a refinement of the geometry, so that the amount of dark matter was much less (someone compared it to the mass of the Voyager space probe.) Then Dr White announced his intention to test whether a "space warp" was possible, by using a Michelson interferometer to try to detect a path-length difference when a voltage was applied to a capacitor ring.

So that stuff was all purely related to Alcubierre "Warp Drive". And of course news media were widely reporting that NASA was researching how to develop a Warp Drive, and the news stories were of course showing pictures of the starship Enterprise from Star Trek. But Shawyer's EMdrive was nowhere in that picture, and was an altogether separate and much less reported story on its own.

Then when the Eagleworks lab got involved in experimental testing to verify the Shawyer EMdrive concept (or Cannae drive, whatever) that's when suddenly the 2 stories began to merge, and speculation was put forth that the EMdrive was somehow a "Q-thruster" and then further that it was a "Warp Drive". Since the actual mechanism - if any - is unknown, what it is seems to depend on who's doing the speculating.
Maybe there is some of that going on out there. But what i am recalling is from this thread. and I think it may have been Mr March or someone directly in a conversation with Mr March in this thread. Again my memory may be faulty on who but not where. It happened here. :) ...or maybe i am insane. :)
When antigravity is outlawed only outlaws will have antigravity.

Offline TheTraveller

How much power are you planning on putting through that coax?  The thicker it gets, the stiffer it gets, which would mess up any delicate movements of the balance beam.  My experience is with amateur radio, and there 50 watts is the most you would try to put through something like RG-59 (looks like cable-TV cable).   RG-8, which can handle a kilowatt, is about 1 cm in diameter and not very flexible at all.

Power losses in the cable of course turn into heat...
Thanks for the feedback.

Did a few years as a ham. You are right. Cable heat losses need to be considered. Will be very small. Max power will be 100W.

What I plan to do is not a lot different to how Shawyer tests is cryo EM Drive variant as attached. Note the scale under the cryo EM Drive and the other above left?

He has been doing this since 2003 or before. Why reinvent the wheel? Follow the path he has made.
« Last Edit: 05/05/2015 06:54 PM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
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Offline Rodal

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I am afraid that Star-Drive...aka Paul March isn't coming back. We had such a productive collaboration. That was open source science happening right before the World's eyes.

We'll reach the stars someday, and you're getting us there...one data point at a time.

There was a time, when a German/US engineer working on ICBM's at the US Army in the early 1950's, at the height of the cold war with the Soviet Union, was allowed to publish a fantastic vision of space exploration first in Collier's magazine and then to appear on TV's Disney's hour to discuss a trip to Mars with a flotilla of spaceships, this at a time before Sputnik, when such a trip to Mars seemed impossible:








Those programs on Disney inspired a generation that motivated them to go into math, physics, and engineering, and there was no backlash from the US Army.

Amazing how times have changed that now discussing future space applications (even if they are impractical like the flotilla of spaceships to Mars was) is met with such backlash at the one organization that should be inspiring young people to go into mathematics, physics and engineering (instead of being condemned to short trips to near-Earth orbit gazing at our own planet).   

:(


Besides, NASA's present Administrator had (previous to Dr.White's papers on warp-drive) made presentations stating that

We Can Only Survive If We Are A Multi-Planet Species


« Last Edit: 05/05/2015 07:13 PM by Rodal »

Offline CW

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Somehow reminds me of the movie Interstellar, when one of the 'bright' guys says something in the vein of "The world doesn't need any more engineers, it needs farmers". Yeeaahh.. right, 'Einstein'. Well.. in the end it is clear that all who thought like that, perished in the story. Which is, uh, all of mankind except for a couple 1000's of (probably pretty smart) people.

EDIT: Actually.. the movie implies that, because only very smart people made it into space and procreate there, their descendants should also be quite a bit smarter in general than the old generations on Earth. An evolutionary jump, if you will, caused by extinction pressure.
;)
« Last Edit: 05/05/2015 07:13 PM by CW »
Reality is weirder than fiction

Offline Flyby

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.....

Amazing how times have changed that now discussing future space applications (even if they are impractical like the flotilla of spaceships to Mars was) is met with such backlash at the one organization that should be inspiring young people to go into mathematics, physics and engineering (instead of being condemned to short trips to near-Earth orbit gazing at our own planet).   

:(

......


I agree with you for a 110%, but i can't help noticing that our current world is rougher, harsher and more aggressive then the 50 or 60's. The way we communicate with each other has become way more aggressive and opinionated/polarized.

I've just read the infamous Forbes article ppl were referring to in the other (article) topic.........sigh... :-\
Blindly aggressive, polarized and opinionated.. I suppose that ridiculing others makes someone a top article writer these days?

Things like this get under my skin...
why not give hard working ppl (Eagleworks & R.Shawyer) give a chance to chase a dream? If it doesn't pan out, no real harm done...
« Last Edit: 05/05/2015 07:26 PM by Flyby »

Offline aceshigh

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EDIT: Actually.. the movie implies that, because only very smart people made it into space and procreate there, their descendants should also be quite a bit smarter in general than the old generations on Earth. An evolutionary jump, if you will, caused by extinction pressure.
;)

which goes against current fact: the 10% smarter people on Earth seems to procreate much more slowly than the other 90%.


maybe this trend is older than we think and is the reason why we are still stuck to Earth.

Offline WarpTech

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while realizing my knowledge of electromagnetism falls short compared to level that is discussed here, i do have a question about that interesting idea on momentum transfer of the waves :

-with the law on conservation of energy in the back of my head -
 
How can the momentum transfer of a wave be bigger then the energy contained in a photon, as seen in a pure photon rocket ? I believe calculations showed the forces observed in the frustum are many times (100? 1000?) greater then what a photon rocket would be able to produce...

Due to the duality of microwave being a photon particle and a wave at the same time, shouldn't the energy contained in a wave/particle be the same?

Is it because for a photon rocket only a small portion of that energy is used for kinetic motion, while in the momentum transfer a greater part of the energy is transferred? ???
Concerning Todd's formulation, I attach below his reply that was posted in another thread, that may also be of help concerning the above question:

COM=conservation of momentum
GR=General Relativity

His answer has to do with the "gravitational field" inside the cavity, which can have different levels of energy :
(in one post he suggested that the experimenters should post a label on the frustum reading "Gravitational Field Inside")
I'm trying to wrap my head around this, so let's see if i got this right...(in simple wording)

Due to the shape of the frustum, energy is gradually compressed going from the large base to the small base. (energy density differs along the longitudinal axis).
 This energy increase also causes a denser gravitational field, effectively slowing down electromagnetic waves, who transfer part of their momentum energy to the frustum...
I can more or less see how "gravitational drag" can cause a forward motion for wave moving towards the small end... but what about the returning waves?

Do they accelerate again when the gravitational field inside the frustum decreases (going from small to large base) , hence nullifying the forward momentum..

or

do they keep their lower energy state on the way back, hence slowly dying out to zero after X bounces?

or.. did i completely miss the point? :'(

I too am still trying to wrap my head around it all, but to answer some of the questions here, I think it is important to understand the relationship of the Energy-momentum 4-vector and how it transforms in a gravitational field. I'm sure we are all aware of the relationship for transverse EM waves where,

E^2 = p^2 * c^2

This can be re-written simply

p = E/c

In free space, no-one would argue with this. However, in the wave guide, as in a gravitational field, c is replaced by a group velocity, then roughly speaking,

p ~ E/v_g

The group velocity is a variable inside the tapered waveguide. So momentum is "amplified" toward the small end, relative to the "conserved" energy input. Momentum is conserved at the expense of a velocity gradient and the motion of the frustum. The gain in momentum is inversely proportional to the reduction in wave velocity.

If we had a photon rocket in a vacuum where the speed of light, c/K << c, it would have a very large thrust! It is the value of c in vacuum that makes it so weak.

Inside the waveguide, you do not need to worry about energy density as you do in GR. It is simply the geometry that is controlling the group velocity, not the energy density. I should be more careful with my words. It is the same principle as "gravity", it "mimics" gravity over a narrow bandwidth, but if you try to apply GR and calculate space-time curvature, you will have a difficult time justifying it. It's not space-time that's curved, it's the taper of the frustum.

Waves that are reflected and are not cut-off by the taper do not contribute much, if anything. They are however, red-shifted when moving backwards, toward the higher v_g end. What I am currently trying to ascertain is whether the wavelengths of these reflected waves bouncing back and fourth, decay over time to longer wavelengths that are then cut-off and absorbed. If that's true, then obviously, having a high Q resonant cavity will amplify the effect enormously. I have a lot of research to do. :)

I"m also wondering if anyone would like to discuss my warp drive technology and how ZPF gravity works, I can start another thread, so as not to clutter the EM Drive thread with other stuff. It would be great if more engineers understood it as I do.

Best Regards,
Todd D.

Offline zen-in

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How much power are you planning on putting through that coax?  The thicker it gets, the stiffer it gets, which would mess up any delicate movements of the balance beam.  My experience is with amateur radio, and there 50 watts is the most you would try to put through something like RG-59 (looks like cable-TV cable).   RG-8, which can handle a kilowatt, is about 1 cm in diameter and not very flexible at all.

Power losses in the cable of course turn into heat...
Thanks for the feedback.

Did a few years as a ham. You are right. Cable heat losses need to be considered. Will be very small. Max power will be 100W.

What I plan to do is not a lot different to how Shawyer tests is cryo EM Drive variant as attached. Note the scale under the cryo EM Drive and the other above left?

He has been doing this since 2003 or before. Why reinvent the wheel? Follow the path he has made.

Eagleworks mounted their PA on the balance beam.   The frequency source could also be custom made and mounted on the balance beam.   That would eliminate the coax problem.
Interesting photograph; I have not seen it before.   The experiment is nicely setup with very good shielding for air currents.   But I don't see how it can be called cryogenic.   It looks like the Nitrogen dewar is just supplying dry Nitrogen.   The apparatus inside the clear boxes and sitting on a postage scale is not a dewar.   Unless he has found a supplier of room temperature superconductors it is not a superconductor test.  Superconducting cavities have to be cooled with liquid Helium and to keep the lHe from boiling off in a flash the lHe dewar has to be surrounded by a liquid Nitrogen dewar.   A high vacuum has to separate the dewars from everything and high IR reflective surfaces and other exotic contrivances are needed.   Otherwise the cryogens boil off and the whole thing turns into a missile.   High temperature superconductors are easier to work with because they only require liquid Nitrogen.  The second picture shows my crufty rotating magnetic field setup.   The white thing is a styrofoam container filled with liquid Nitrogen and the dut (device under test).   
« Last Edit: 05/05/2015 08:04 PM by zen-in »

Offline PaulF

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BTW, I think Mr. Shawyer claimed that there was no dielectric inserted into his cavity at all because it was not needed for its functioning. Technically though, that's not possible with materials like copper and aluminum. They instantly oxidize during manufacture of the cavity. So, the standing EM waves will encounter a dielectric on any metallic surface.
Would a copper or aluminium (british :) ) alloy, one that does not oxidize easily, do the trick or would that never provide enough reflectivity for the microwaves?

Because what you are stating is that even mr. Shawyer never had a thruster without dielectric. And thus measurements without dielectric do not exist...

Offline CW

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EDIT: Actually.. the movie implies that, because only very smart people made it into space and procreate there, their descendants should also be quite a bit smarter in general than the old generations on Earth. An evolutionary jump, if you will, caused by extinction pressure.
;)

which goes against current fact: the 10% smarter people on Earth seems to procreate much more slowly than the other 90%.


maybe this trend is older than we think and is the reason why we are still stuck to Earth.

True. However, schools and universities serve as a filtering mechanism. There is a clear tendency for highly educated and intelligent people to marry each other and procreate. Rarely will you find a couple with a highly incompatible intellectual profile. Hence, over time, our modern societies create an pre-filtered work evironment that literally promotes genetic reinforcement of certain properties, for instance greater-than-average intelligence, within their specific metiers. I remember a TEDtalks presentation that stressed that aspect of our modern world (sorry, no link right now). Pretty interesting stuff :) .
Reality is weirder than fiction

Offline Flyby

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to Todd D.

Thank you for replying in such an elaborated way!
 
As you've noticed by my wording, I do not have a scientific background and most certainly will need to reread your reply several times.
On top of that,  English is only my 3rd language so assessment of what's being said is obviously a slow process on it self.
But, I must say that,  since a few months, this EMdrive topic forced me to study some aspects of science and math I've never seen before.
All in all, not a bad thing... :P

It is on rare moments like these, that i have a tiny tiny regret for not having taken the path of a nuclear science engineer, but architecture instead...a difficult choice i made decades ago...
« Last Edit: 05/05/2015 08:25 PM by Flyby »

Offline Rodal

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Yesterday I was too busy with other work, and I gave the benefit of the doubt to posters that insisted that there was new information supplied by R. Shawyer.

Upon further inspection, it is immediately evident from looking at Shawyer's paper that this is not new information.

The way that R. Shawyer defines R2 and R1 and L1, it necessarily follows that L1 must be such that L1=R2-R1

This is a tautology, and as such it cannot be described as "new information", any more than supplying another paper stating that R2=R1+L1 could claimed to be new information, and then supplying another paper stating that R1=R2-L1 could claimed to be new information, or supplying another paper defining a new variable R3=R1+R2 is new information, or supplying another paper defining a new variable R4=Sqrt[R1^2+R2^2].  One can construct endless definitions, definitions of new variables don't provide any new information.

New information would be to supply the dimensional value of R1 and R2 (from which L1 necessarily follows and it would be unnecessary, superfluous and bad engineering drawing practice to also give).


http://forum.nasaspaceflight.com/index.php?topic=36313.msg1369066#msg1369066
« Last Edit: 05/05/2015 08:29 PM by Rodal »

Offline TheTraveller

Eagleworks mounted their PA on the balance beam.   The frequency source could also be custom made and mounted on the balance beam.   That would eliminate the coax problem.
Interesting photograph; I have not seen it before.   The experiment is nicely setup with very good shielding for air currents.   But I don't see how it can be called cryogenic.   It looks like the Nitrogen dewar is just supplying dry Nitrogen.   The apparatus inside the clear boxes and sitting on a postage scale is not a dewar.   Unless he has found a supplier of room temperature superconductors it is not a superconductor test.  Superconducting cavities have to be cooled with liquid Helium and to keep the lHe from boiling off in a flash the lHe dewar has to be surrounded by a liquid Nitrogen dewar.   A high vacuum has to separate the dewars from everything and high IR reflective surfaces and other exotic contrivances are needed.   Otherwise the cryogens boil off and the whole thing turns into a missile.   High temperature superconductors are easier to work with because they only require liquid Nitrogen.  The second picture shows my crufty rotating magnetic field setup.   The white thing is a styrofoam container filled with liquid Nitrogen and the dut (device under test).
Here is what is inside the shiny metal cylinder. An EM Drive with a superconducting inner surface.

According to Shawyer it is designed to be cooled by liquid Nitrogen and it's super-conducting surfaces are formed from YBCO thin films on sapphire substrates.
« Last Edit: 05/05/2015 08:27 PM by TheTraveller »
"As for me, I am tormented with an everlasting itch for things remote. I love to sail forbidden seas.
Herman Melville, Moby Dick

Offline tea monster

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The Disney/Von Braun films of the 50's were based on solid, mathematically provable science and physics. Apart from building the ships, all the concepts were based on solid, proven rules of nature.

The EM drive is nowhere near that stage. None of the physics of how it works are proven and its operation as described seems to violate the conservation of energy.

It could well be that we are on the cusp of a new wonderful age of innovation. Or we may be looking at another Dean drive. Until we know for certain, nobody is going to be producing films for Disney.

If it is proven to work as described (and we should know soon), then there will be plenty of excitement, magazine articles and documentaries.

Offline StrongGR

As far as I can tell, I am not the only one to have thought to a general relativity effect here. This paper uses a modified version of Einstein equations to explain what is going on in a conical resonant cavity without violating momentum conservation. The point is that the author uses a weak perturbation approximation and I do not know if this is fully justified.

Offline FutureStormtrooper

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Maybe someone can tell him we've settled down here.  Did the tumult from a few of the new thread participants because of the new publicity discourage him?

I sent him an Email at his nasa.gov address letting him know essentially that last night. Didn't hear back, but time will tell.

Offline Rodal

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As far as I can tell, I am not the only one to have thought to a general relativity effect here. This paper uses a modified version of Einstein equations to explain what is going on in a conical resonant cavity without violating momentum conservation. The point is that the author uses a weak perturbation approximation and I do not know if this is fully justified.

I had read that paper. Unfortunately, as the author of the paper states:

Quote
The weakest part of the theory seems to be that there is no clear way of preventing large gravitational effects due to the magnetic field of the Earth, as predicted by Eq. (17)

Therefore the author himself admits that his model is contradicted by predicting large gravitational effects due to the Earth's magnetic field that are contrary to all experimental evidence.
« Last Edit: 05/05/2015 08:36 PM by Rodal »

Offline sanman

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From what I remember, originally there was the Alcubierre "Warp Drive" concept proposed by Mexican physicist Miguel Alcubierre, which required a jupiter-sized mass of dark matter. Then Dr White came up with a refinement of the geometry, so that the amount of dark matter was much less (someone compared it to the mass of the Voyager space probe.) Then Dr White announced his intention to test whether a "space warp" was possible, by using a Michelson interferometer to try to detect a path-length difference when a voltage was applied to a capacitor ring.

So that stuff was all purely related to Alcubierre "Warp Drive". And of course news media were widely reporting that NASA was researching how to develop a Warp Drive, and the news stories were of course showing pictures of the starship Enterprise from Star Trek. But Shawyer's EMdrive was nowhere in that picture, and was an altogether separate and much less reported story on its own.

Then when the Eagleworks lab got involved in experimental testing to verify the Shawyer EMdrive concept (or Cannae drive, whatever) that's when suddenly the 2 stories began to merge, and speculation was put forth that the EMdrive was somehow a "Q-thruster" and then further that it was a "Warp Drive". Since the actual mechanism - if any - is unknown, what it is seems to depend on who's doing the speculating.
Maybe there is some of that going on out there. But what i am recalling is from this thread. and I think it may have been Mr March or someone directly in a conversation with Mr March in this thread. Again my memory may be faulty on who but not where. It happened here. :) ...or maybe i am insane. :)

And besides that, Paul March was initially involved with research on Prof Woodward's "Mach Effect"  theory, which is again something altogether different from Alcubierre warp drive and EMdrive. Mach Effect as of yet cannot be claimed to violate the established laws of physics, and is supposedly a prerequisite or necessary consequence of Einstein's Relativity.

But so the Woodward Mach Effect experiments were about oscillating masses, weren't they? They were not the same type of apparatus as the EMdrive.

So when I see people mentioning warp drive, Woodward's theory, and EMdrive all in the same thread, it kind of looks like the lines are being blurred here. These things originally started out as completely distinct from each other - they were 3 separate things - and now it looks like they're all being mashed together in the thread discussions. Perhaps it's because the same researchers at Eagleworks have been involved in investigating all 3 things.

Offline Rodal

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From what I remember, originally there was the Alcubierre "Warp Drive" concept proposed by Mexican physicist Miguel Alcubierre, which required a jupiter-sized mass of dark matter. Then Dr White came up with a refinement of the geometry, so that the amount of dark matter was much less (someone compared it to the mass of the Voyager space probe.) Then Dr White announced his intention to test whether a "space warp" was possible, by using a Michelson interferometer to try to detect a path-length difference when a voltage was applied to a capacitor ring.

So that stuff was all purely related to Alcubierre "Warp Drive". And of course news media were widely reporting that NASA was researching how to develop a Warp Drive, and the news stories were of course showing pictures of the starship Enterprise from Star Trek. But Shawyer's EMdrive was nowhere in that picture, and was an altogether separate and much less reported story on its own.

Then when the Eagleworks lab got involved in experimental testing to verify the Shawyer EMdrive concept (or Cannae drive, whatever) that's when suddenly the 2 stories began to merge, and speculation was put forth that the EMdrive was somehow a "Q-thruster" and then further that it was a "Warp Drive". Since the actual mechanism - if any - is unknown, what it is seems to depend on who's doing the speculating.
Maybe there is some of that going on out there. But what i am recalling is from this thread. and I think it may have been Mr March or someone directly in a conversation with Mr March in this thread. Again my memory may be faulty on who but not where. It happened here. :) ...or maybe i am insane. :)

And besides that, Paul March was initially involved with research on Prof Woodward's "Mach Effect"  theory, which is again something altogether different from Alcubierre warp drive and EMdrive. Mach Effect as of yet cannot be claimed to violate the established laws of physics, and is supposedly a prerequisite or necessary consequence of Einstein's Relativity.

But so the Woodward Mach Effect experiments were about oscillating masses, weren't they? They were not the same type of apparatus as the EMdrive.

So when I see people mentioning warp drive, Woodward's theory, and EMdrive all in the same thread, it kind of looks like the lines are being blurred here. These things originally started out as completely distinct from each other - they were 3 separate things - and now it looks like they're all being mashed together in the thread discussions. Perhaps it's because the same researchers at Eagleworks have been involved in investigating all 3 things.
Or perhaps they are connected as there are countless examples I can give in physics where what was supposed to be earlier theories (thought to be very different at the time) they turned out to be incomplete parts of a bigger theory encompassing them.  Many examples: Schrodinger wave equation and Heissenberg's matrix formulation,   Five consistent versions of string theory were developed until it was realized in the mid-1990s that they were different limits of a conjectured single 11-dimensional theory now known as M-theory. etc etc   I can go on and on...

(Of course, I know that Schrodinger, Heisenberg, and Witten are on a complete different scale to the level of the present "theories" , but you get the point of what Paul March refers to when he states that QV and ME may be different sides of the same coin)
« Last Edit: 05/05/2015 08:58 PM by Rodal »

Offline zen-in

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Eagleworks mounted their PA on the balance beam.   The frequency source could also be custom made and mounted on the balance beam.   That would eliminate the coax problem.
Interesting photograph; I have not seen it before.   The experiment is nicely setup with very good shielding for air currents.   But I don't see how it can be called cryogenic.   It looks like the Nitrogen dewar is just supplying dry Nitrogen.   The apparatus inside the clear boxes and sitting on a postage scale is not a dewar.   Unless he has found a supplier of room temperature superconductors it is not a superconductor test.  Superconducting cavities have to be cooled with liquid Helium and to keep the lHe from boiling off in a flash the lHe dewar has to be surrounded by a liquid Nitrogen dewar.   A high vacuum has to separate the dewars from everything and high IR reflective surfaces and other exotic contrivances are needed.   Otherwise the cryogens boil off and the whole thing turns into a missile.   High temperature superconductors are easier to work with because they only require liquid Nitrogen.  The second picture shows my crufty rotating magnetic field setup.   The white thing is a styrofoam container filled with liquid Nitrogen and the dut (device under test).
Here is what is inside the shiny metal cylinder. An EM Drive with a superconducting inner surface.

According to Shawyer it is designed to be cooled by liquid Nitrogen and it's super-conducting surfaces are formed from YBCO thin films on sapphire substrates.

OK I see how that works now; just a liquid Nitrogen dewar with the dut suspended in it.   Very similar to my setup.   Nitrogen boil-off will affect the lower scale but not the one that supports the dut so much.   I would imagine there is a lot of boil-off during a test.     YBCO thin films have high AC losses; typically above 60 Hz.   No doubt these are specially designed to minimize those lossses.   

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