Author Topic: EM Drive Developments Thread 1  (Read 765581 times)

Offline frobnicat

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Re: EM Drive Developments
« Reply #1260 on: 10/02/2014 05:36 PM »
Quote
Time permitting I will try to find and read it. If I don't find it factual you owe me a bear.
If it isn't enjoyable I'll owe you a beer, or a scotch or whatever, but not a bear.  Bear's are expensive and ill-mannered.

Yeah, well, right,  ;D
Thanks for the sensible clarifications and your effort to share your views.

Offline Mulletron

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Re: EM Drive Developments
« Reply #1261 on: 10/02/2014 05:54 PM »
Well this forum is getting a bit out of hand here. Truth is, nobody knows how this darn thing works. At this point we don't even know if it works. The folks working at the coal face of this research have theories just as we do. I personally have posted on here a few very different ideas I had and from others, but none of that really matters because it is just speculation. I think we should be mindful to separate the "how" from the "why" until the effect has been scaled up and proven/dis proven. If this thing is shown experimentally to be real and is undeniable, then the rest of the scientific community will jump in and rewrite physics to explain it. I can tell you, as you already know that most theoretical physicist won't touch this until it is undeniable because it is a taboo subject and could damage their reputation. In addition to that, the very notion of the emdrive actually working puts their sacred cows like the precision of GR in jeopardy, not to mention supersymmetry and string theory. It is best to play nice with each other and don't toot our own horns too early and fall in love with our or others theories. Folks can submit research papers all day about x or y, but it doesn't amount to a hill of beans unless an experiment backs it up.
Challenge your preconceptions, or they will challenge you. - Velik

Offline raketa

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Re: EM Drive Developments
« Reply #1262 on: 10/02/2014 06:02 PM »
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The experimental setup is not the trouble.  Since they cannot do a real evaluation of theory, what they've asked for is more thrust, which is what Jim is working on.

That makes no sensible sense to me. In this context this would be an application driven research ? So the trouble is the experimental setup. Why should they care about theories ? If the effect is hinting at being anything like it says it is, then pour the money and hire the third party experimentalists to do an all or nothing confirmation of any real effect at all. Even if all it takes is a mW thruster mounted on an atomic force microscope cantilever to get a few pN of thrust, just to see it's real. Then make phenomenological model. Then build better/bigger devices and see if it fits such or such ground breaking theory.
Even if the fact to pursue a higher thrust might contribute to show this is not a real effect and therefore allow for a progress, my point is that putting the focus on that is not the best way to assert the reality of any effect at all.
Again, the "this is impossible" hypothesis appears not well accommodated by the strategy.
I think we're talking past each other because you're not familiar with what I've been relating, which is Woodward's work.  I have little interest in the work at Eagle because I know the QVF hypothesis is wrong.  The Eagle work interests me in as much as it may be stumbling across M-E evidence, but this would be by mistake.  For example, it works only with a  dielectric and during switching transients which bear enough in common with an AC signal they can produce decent thrust.  But the DC signal doesn't do this.

Keep in mind the contrast here.  Woodward's scheme does not violate conservation.  There's nothing "new" in his work, nor any contradictions with conventional science.  In fact, while explaining his work, he very ably answered questions about the classical and semi-classical electron models we've had for decades, and as I said, he deserves a Nobel for this alone.  I'm not suggesting you skip ahead, but chapter 7 is a nail-biter.

In any event, I agree the "this is impossible" kinds of statements are unhelpful.  And the statement that QVF violates conservation is not really true.  That's a distraction fallacy intended to be later explained away as one becomes aware of what QVF is proposing.  However what is not a distraction is that QVF violates Einstein's Equivalence Principle (EEP).  In that scheme, the virtual proton/electron pairs cannot gravitate or they would have collapsed the universe, and yet they mediate momentum transfer.  This means they have to have different values for their gravitational and inertial masses, which violates EEP and all of GR.  QVF is therefore not true.

Woodward's work has done the opposite of deny what we know about life the universe and everything.  He has added to what we know by explaining how the surface of the electron can spin at 100c.  This is an amazing accomplishment since before Woodward's work, that seemed like a violation of GR, and as it turns out, it is required by GR.

As to your frustration in general, I feel your pain.  I would just point out however, that frustration does not justify failure to do due diligence.  As I explained earlier, the experimental setup does not lend itself to the kinds of simplification you're requiring.  You therefore need to invest the time to look at how the setup actually works, rather than stipulate it ought to work how you'd like.  The self-contained setup is NOT the best setup for the work Woodward has been doing to date.  Along these same lines I'd note to you, that you justify the work of others who did not provide vacuum, and appear to presume Woodward did not provide vacuum.  This is not true.  All of the spurious sources one can imagine have been dealt with one by one on Woodward's balance, including thermal, ion, Dean Drive effects, displacement effect, etc.  All of this is in the book.

http://www.amazon.com/Making-Starships-Stargates-Interstellar-Exploration/dp/1461456223

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Time permitting I will try to find and read it. If I don't find it factual you owe me a bear.
If it isn't enjoyable I'll owe you a beer, or a scotch or whatever, but not a bear.  Bear's are expensive and ill-mannered.
Interesting. I will definitely read book.

Offline Rodal

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Re: EM Drive Developments
« Reply #1263 on: 10/02/2014 06:09 PM »
Sciama lived until December 19, 1999. 

If anyone knows of a paper that Sciama wrote commenting on transient fluctuations in the local proper energy density as being a possible means for propellant-less propulsion, or a local violation of momentum-conservation, please let us know, as it would be of much interest.

This is a link to one of the last Sciama's papers published, in 1994: "On the Interaction Between Cosmic Rays and Dark Matter Molecular Clouds in the Milky Way. l Basic Considerations"

http://cds.cern.ch/record/389845/files/9906159.pdf?version=1

and this is a paper on "Astrophysical evidence for the existence of black holes" he submitted in 1999:

http://arxiv.org/abs/astro-ph/9912186
« Last Edit: 10/02/2014 06:29 PM by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1264 on: 10/02/2014 06:44 PM »
I don't think Sciama ever did that.  I think that is Woodward's claim to fame.  First place the notion was published was probably "Measurement of a Machian Transient Mass Fluctuation," Foundations of Physics Letters 4, 407- 423 (1991).

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1265 on: 10/02/2014 07:09 PM »
I think we should be mindful to separate the "how" from the "why" until the effect has been scaled up and proven/dis proven.

With this sentence, I suddenly realized the validity of separating experiment from theory.
« Last Edit: 10/03/2014 07:48 AM by JohnFornaro »
Sometimes I just flat out don't get it.

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1266 on: 10/02/2014 07:09 PM »
Yes, the basic issue is whether rest mass can change at the particle level and not just as a rearrangement of kinetic energy.
Woodward has never suggested we can alter the rest mass of particles, but rather only of bulk mass items that store Mach Effects or mass fluctuations in the interatomic energy bonds.  In fact, all bulk matter stores delta mass during deformation, since deformation changes the energy in these bonds and energy = mass X c^2.
« Last Edit: 10/02/2014 07:10 PM by Ron Stahl »

Offline wembley

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Re: EM Drive Developments
« Reply #1267 on: 10/02/2014 07:21 PM »
...
But I don't think he uses that approach any more:
"The first thruster built by SPR Ltd and tested in 2003 also used a dielectric section, but to obtain our subsequent high thrust levels, we abandoned the dielectric and concentrated on our present cavity design."
Where is the above quotation from? (I would appreciate a link for it so that I can further understand the context)

Thanks for your response

_________
PS: I looked for it , but I could not find that statement in this 2006 report:   http://www.newscientist.com/data/images/ns/av/shawyertheory.pdf

This was in an email from Dr Shawyer in response to the NASA paper. Have you tried contacting him?

Offline JohnFornaro

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Re: EM Drive Developments
« Reply #1268 on: 10/02/2014 07:27 PM »
Quote from: JF
...these few pages are not a complete derivation of the operating principles

When there are equations, I prefer to just go with equations -that's my personal viewpoint. If I am missing some new equation, I would appreciate it being pointed out. Thank you.

My math whiz friend asked me to supply a derivation regarding these equations.  I could not do this, and scanned those pages, because I thought that the derivation resided in that passage.  so I just threw it out to the community here.

I realize that I asked for a lot up thread, when I requested an equational line of reasoning which started with, say, e=Mc^2 and resulted in propellantless drive or an explanation of inertia.`
Sometimes I just flat out don't get it.

Offline Rodal

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Re: EM Drive Developments
« Reply #1269 on: 10/02/2014 07:42 PM »
...
But I don't think he uses that approach any more:
"The first thruster built by SPR Ltd and tested in 2003 also used a dielectric section, but to obtain our subsequent high thrust levels, we abandoned the dielectric and concentrated on our present cavity design."
Where is the above quotation from? (I would appreciate a link for it so that I can further understand the context)

Thanks for your response

_________
PS: I looked for it , but I could not find that statement in this 2006 report:   http://www.newscientist.com/data/images/ns/av/shawyertheory.pdf

This was in an email from Dr Shawyer in response to the NASA paper. Have you tried contacting him?

Thank you for your response.  I understand that Shawyer knows that you (if I recall correctly, please forgive me and correct me if I'm wrong) are a writer with contributions to AviationWeek and Wired, as he disclosed the above information to you.

I am not in the media, and thus I treat communications with me as private, and I only discuss in forums information that is generally available to the public.  Thus, from this viewpoint you are in a better position than me to gather and release such information  :)

Offline Rodal

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Re: EM Drive Developments
« Reply #1270 on: 10/02/2014 07:44 PM »
I found this intriguing, interesting pre-publication paper by Sciama, which he wrote in 1954, about a year after his paper on the origins of inertia that is used by Woodward for his transient formulation.

"On a possible method of shielding gravitation"
http://gravityresearchfoundation.org/pdf/awarded/1954/sciama.pdf

Since this typewritten paper with handwritten notes is pre-publication, I checked its legitimacy:

<<Dennis Sciama who wrote on a possible method of shielding gravitation using Mach’s principle.>> page 9 of "The Role of Gravitation in Physics, Report from the 1957 Chapel Hill Conference"  http://www.edition-open-access.de/media/sources/5/Sources5.pdf

This paper by Sciama is very interesting because:

Sciama concludes that the universe must contain an assembly of masses with negative energy

Sciama considers the covariant inertial-gravitational field metric and the covariant matter field.  Sciama examines the equations from the viewpoint of a rotating frame.  Sciama concludes that there must be extra negative terms in the covariant matter field, and that these terms are due to particles carrying the gravitational field, possessing negative energy.  He also concludes that they should have gravitational repulsion and could be used as a gravity shield.

Sciama does not use the transient fluctuation as justification for this negative energy particles, actually their origin and existence is not at all related to the "wormhole" square term in Woodward's formulation.  I find that noteworthy, that Sciama travels this completely different road (than Woodward) towards negative energy.
« Last Edit: 10/02/2014 07:48 PM by Rodal »

Offline raketa

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Re: EM Drive Developments
« Reply #1271 on: 10/02/2014 07:47 PM »
Start to read Woodward book and it is fascinating. It remembers me The Feynman Lectures on Physics. Instead of usual approach trying confuse crowd, because they  don't understand and try cover up it, James try to explain what we know how we know.
Love example of Galileo about law of movement, how everybody could see how far ball  is go  base on smoothness of surface, but nobody want to change it and have idea to see that will move indefinitely if not friction, which was obvious if  you are able to look without prediction.
Interesting discussion about inertia, looks like we are back at the beginning of 20 century and going adjust  STR , like Einstein had adjust Newton physic  Fascinating. EM Drive is just byproduct of rethinking of understanding of our universe. Einstein through his theory practically close our universe for travelling to stars and Woodward maybe open it again as possible scenario. It is so excited to live in this time, in all frontier we are moving forward like didn't happen for last 40 years. In decade maybe Mars(because Spacex), in 20-30 years interstellar probe if EM drive will work.

Offline Mulletron

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Re: EM Drive Developments
« Reply #1272 on: 10/02/2014 08:03 PM »
http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?letter=.&classic=YES&bibcode=1953MNRAS.113...34S&page=&type=SCREEN_VIEW&data_type=PDF_LOW&send=GET&filetype=.pdf

Sciama's 1953 paper above.

I gotta say IMHO of course, I am completely anti Machian and derivatives such as Sciama's take on inertia. Let me explain:

Mach's ideas come from a time where he didn't enjoy the benefit of anything QM. He didn't even believe that atoms exist I read somewhere.

Sciama mentions in his introduction accelerations in reference to the fixed stars. His ideas didn't enjoy the benefit of knowing the universe is expanding and accelerating.

For the life of me, I cringe when I read things such as local matter interacting with the distant matter of the universe, that kind of stuff. This isn't relevant anymore. How can we get instantaneous thrust if the action depends on a gravinertial field propagating at C.

What makes more sense to me are the various theories which explain the origin of inertia as quantum phenomena. Quantum effects are local, here, and now.

http://calphysics.org/index.html

http://arxiv.org/find/physics/1/au:+McCulloch_M/0/1/0/all/0/1 
(similar to above but further modifies inertia when in an environment with very low accelerations)

This emdrive thing has taken up a lot of my time lately, not so much as if or why it works. I have discovered that the jury is out on so many fundamental scientific concepts which I thought were nailed down, like inertia, origin or mass (not simply/only Higgs) and dark matter/energy. The dark energy/matter thing really bugs me. They were clearly invented to explain away inadequacies in theory attempting to explain observation. Instead of revising theory, more "crap" was piled on to fix it. Kinda like the games renormalization plays; card tricks. I think the current state of science is in bad shape in that theory has trumped observation. I get that it is important to spend time/money looking for new particles/gravity waves, etc. But I see little effort from mainstream science to go back and question itself when nothing new is found. One can ride a bunk theory for years and build a career of it. Then we end up with unfalsifiable theories like string theory or more particles like superpartners. Gravinertial fields are yet another invention to address something happening here and now that isn't explained by current accepted theory. Thus I am excited when I read things like "Anomalous Thrust Production from an RF Test Device" because if it really is true, it will really shake up the old tired paradigm I briefly ranted about above. It would do science a service if we would "play with what we got", instead of creating new theories to play with. GR hasn't let us down yet, but it is macro. There is a gap between macro and micro which could be filled in by modifying GR on its boundaries where appropriate, instead of treating it as complete. Einstein doesn't have an ego anymore. I admire Hawking for continually adjusting to the times.







 
Challenge your preconceptions, or they will challenge you. - Velik

Offline Rodal

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Re: EM Drive Developments
« Reply #1273 on: 10/02/2014 08:04 PM »
Also, Sciama, in his paper

"On a possible method of shielding gravitation"
http://gravityresearchfoundation.org/pdf/awarded/1954/sciama.pdf

accepts the fact that the boundary conditions for the equations of General Relativity are not specified and this is a subject of controversy, particularly regarding conclusions as in Sciama's Mach theory.

I have previously addressed the issue of boundary conditions in a comment from @Mulletron regarding the Unruh effect.

This issue (of boundary conditions in General Relativity) is very important for Sciama's theory, particularly for the approximation used by Sciama, for his inertial effect (the terms in a perturbation of GR are not decreasing rapidly such that one can neglect the far field).  In fact the far-field is critical for Sciama's inertial theory, and definitely for Woodward fluctuation theory (dealing with 2nd order derivatives).
« Last Edit: 10/02/2014 08:07 PM by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1274 on: 10/02/2014 08:06 PM »
He also concludes that they should have gravitational repulsion and could be used as a gravity shield.
This is a common mistake even physicists make very often.  Although negative mass has negative gravitational action and is thus repelled by other matter, it also has negative inertial action so the direction of the former is reversed by the latter.  So negative mass actually acts like normal mass, despite it's backward inertia.

Offline Rodal

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Re: EM Drive Developments
« Reply #1275 on: 10/02/2014 08:14 PM »
He also concludes that they should have gravitational repulsion and could be used as a gravity shield.
This is a common mistake even physicists make very often.  Although negative mass has negative gravitational action and is thus repelled by other matter, it also has negative inertial action so the direction of the former is reversed by the latter.  So negative mass actually acts like normal mass, despite it's backward inertia.
This is from a paper written by Sciama one year after he wrote the 1953 paper that Woodward uses as the foundation for his transient equations based on Machian inertia. Please reconsider your statement that Sciama made a mistake in 1954 in not properly considering  Machian "inertial action"
Sciama's negative energy particles in this paper are not due to or related to what Woodward considers negative energy due to the quadratic of the transient term.
« Last Edit: 10/02/2014 08:27 PM by Rodal »

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1276 on: 10/02/2014 08:24 PM »
How can we get instantaneous thrust if the action depends on a gravinertial field propagating at C.
This is an excellent question and holds for EM fields as well as gravitational.  Wheeler and Feyman's answer is found in their absorber theory:

http://en.wikipedia.org/wiki/Wheeler–Feynman_absorber_theory

Since Maxwell's equations have two solutions, both forward in time (retarded wave) and backward in time (advanced wave), they chose to use them both to explain instantaneity or the "action at a distance" problem.  Woodward merely applied this same theory to gravitation as is explained in his book.  I'd note if you don't like this explanation so far as inertia and gravity are concerned, then you should apply this same objection to all field theory, without which we would for instance have no electric motors.

Note too, the very nice dovetail this makes with John Cramer's Transactional Interpretation of QM.  You'll find that in the book as well.

Offline Ron Stahl

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Re: EM Drive Developments
« Reply #1277 on: 10/02/2014 08:30 PM »
He also concludes that they should have gravitational repulsion and could be used as a gravity shield.
This is a common mistake even physicists make very often.  Although negative mass has negative gravitational action and is thus repelled by other matter, it also has negative inertial action so the direction of the former is reversed by the latter.  So negative mass actually acts like normal mass, despite it's backward inertia.
This is a paper from a paper written by Sciama one year after he wrote the 1953 paper that Woodward uses as the foundation for his transient equations based on Machian inertia. Please reconsider your statement that Sciama made a mistake in 1954 in not properly considering  Machian "inertial action"
Sciama's negative energy particles in this paper are not due to or related to what Woodward considers negative energy due to the quadratic of the transient term.
Yes.  That's completely correct.  Sciama is of course right that negative gravitational action comes from negative gravitational mass, but IIRC, he failed to note the negative inertial action reverses this otherwise backward action, and I have seen many physicists do this same thing.  I myself presumed if negative mass were a natural state of matter, that it would be scarce since it would be repelled by normal mass, but Woodward corrected me that although it would want to fall away from all matter, it would fall toward it because of the reversed inertial sign.  As it turns out, we're surrounded by negative matter but didn't realize it until Woodward's discovery.

Offline 93143

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Re: EM Drive Developments
« Reply #1278 on: 10/02/2014 08:36 PM »
Sciama mentions in his introduction accelerations in reference to the fixed stars. His ideas didn't enjoy the benefit of knowing the universe is expanding and accelerating.

He knew it was expanding.  Isn't that what a "Robertson-Walker" metric means?  Y'know, more or less...

Quote
This isn't relevant anymore.

http://arxiv.org/pdf/1208.3096v2.pdf

negative inertial action reverses this otherwise backward action

Isn't that only true for the negative mass?  Positive mass would still be repelled by it.
« Last Edit: 10/02/2014 08:39 PM by 93143 »

Offline Rodal

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Re: EM Drive Developments
« Reply #1279 on: 10/02/2014 08:44 PM »
negative inertial action reverses this otherwise backward action

Isn't that only true for the negative mass?  Positive mass would still be repelled by it.

And therefore would act as a gravity shield against our planet's (positive mass) attraction, which was the whole point of Sciama's 1954 paper.
« Last Edit: 10/02/2014 08:50 PM by Rodal »

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