Author Topic: EM Drive Developments - related to space flight applications - Thread 11  (Read 646682 times)

Offline meberbs

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       thankyou for your excellent references.
Have you read any of them? If so I would expect you to make some acknowledgement of the content, rather than the actual content of you post which is mostly a series of falsehoods about me.

Unlike you I am not trying to insult anyone,
Then how come you keep repeating things that I have repeatedly explained to you why they are insulting? And why have you not apologized for them?

Also, I am not aware of any time I said something insulting, so I certainly have not done so intentionally. By the way I also find it inappropriate how you keep assigning motives behind my words that simply are not there.

I am simply saying that you are too easily satisfied and too quick to reject potentially interesting experimental evidence.  It is a bad plan to reject any evidence on the basis that it challenges your presumptions.
Yet another case of you assigning actions to me that I have not done. You accuse me with rejecting experimental evidence, when you have not provided any experimental evidence for me to reject. In fact, you are the one who has rejected evidence in this conversation apparently for no other reason than a refusal to accept that scientific theories which are known to be self-consistent are in fact self-consistent.

Science is an open investigation of reality, there is reason in consideration of the possibility that we do not yet have a perfect definition of electromagnetic interaction.
Except there is no reason. Electromagnetic interactions have been tested, and are consistent with theory across a huge range of scales. It is not reasonable to reject the countless experiments that have been done. Besides which, you haven't "asked about the possibility." You have straight asserted inconsistencies where there are none.

There are good reasons not to reject difficult questions.
I have given responses to all of your questions. In the past you have repeatedly ignored even straightforward questions I have asked of you.

If it offends you that other people choose to pursue this, well good for you, go get a better hobby would be my advice.
Try reading my posts again, what is offensive is when you start with an assumption that is equivalent to "scientists are all idiots," by insisting that inconsistencies exist in theories that countless scientists have reviewed and agreed that they are consistent. The first time maybe you never did any research on your own and thought that there were flaws, but you have been repeating the claim over and over again, while adding no evidence to support it and after you have been provided with evidence contrary to your claim. It is also offensive when you misrepresent things that I have previously said.

Offline meberbs

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...
There was never any practical evidence in the early tests and data that supports scalability. Nothing to say that a larger or smaller frustum, functioning at higher or lower frequencies or power levels, would produce similar results. A great deal of speculation, but data?

I don’t know if there is any practical potential in the EmDrive concept. At the same time I don’t believe that any test data in the public domain proves that there is no practical potential. Even a few ounces of propellant less thrust, could revolutionize the space industry from low earth orbit on...
The problem with "proves that there is no practical potential" is the typical problem with proving a negative. There is always going to be some other variable or combination that hasn't been tested. This is why I think it is important to set some kind of defined boundaries for when to call it a dead end.

At this point with the available data, there is certainly some additional final testing that can reasonably be done, as there are a few ongoing experiments that haven't been finalized. But given that there is little in potentially positive data that hasn't been countered with more sensitive experiments I am not sure how much more is reasonable. It is also useful to keep in mind that electrodynamics really has been well tested in a wide range of regimes, spanning everything that occurs in an emDrive. This is why from the beginning it was just short of certain that the data that showed thrust was nothing other than experimental errors.

As to your suggestion for higher power tests, there were issues with magnetrons, and their poor frequency stability, which is a problem for matching good resonance, it could be done, but despite the lower total power, more recent tests have been more sensitive in a force/power ratio sense. I am not going to tell anyone not to run an experiment (unless there are clear flaws that would make the experiment useless), I would just suggest defining in a precise sense what "good enough" means for what testing you want to do. (Even if you aren't planning on funding or doing more testing yourself, you can still state your opinion on what you think is worthwhile.)

Offline flux_capacitor

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https://arxiv.org/abs/1712.07962

A paper by J. S. Farnes proposes a negative mass model of cold dark matter and dark energy. By adding a Creation Tensor to the model, constantly adding negative-mass dark matter to the cosmos, the accelerating expansion of the universe is preserved. Interestingly, his "toy model" also predicts Dark Matter Halos around galaxies.

Quote from: Abstract
Dark energy and dark matter constitute 95% of the observable Universe. Yet the physical nature of these two phenomena remains a mystery. Einstein suggested a long-forgotten solution: gravitationally repulsive negative masses, which drive cosmic expansion and cannot coalesce into light-emitting structures. However, contemporary cosmological results are derived upon the reasonable assumption that the Universe only contains positive masses. By reconsidering this assumption, I have constructed a toy model which suggests that both dark phenomena can be unified into a single negative mass fluid. The model is a modified ΛCDM cosmology, and indicates that continuously-created negative masses can resemble the cosmological constant and can flatten the rotation curves of galaxies. The model leads to a cyclic universe with a time-variable Hubble parameter, potentially providing compatibility with the current tension that is emerging in cosmological measurements. In the first three-dimensional N-body simulations of negative mass matter in the scientific literature, this exotic material naturally forms haloes around galaxies that extend to several galactic radii. These haloes are not cuspy. The proposed cosmological model is therefore able to predict the observed distribution of dark matter in galaxies from first principles. The model makes several testable predictions and seems to have the potential to be consistent with observational evidence from distant supernovae, the cosmic microwave background, and galaxy clusters. These findings may imply that negative masses are a real and physical aspect of our Universe, or alternatively may imply the existence of a superseding theory that in some limit can be modelled by effective negative masses. Both cases lead to the surprising conclusion that the compelling puzzle of the dark Universe may have been due to a simple sign error.

EDIT: The author wrote this entry as well

https://theconversation.com/bizarre-dark-fluid-with-negative-mass-could-dominate-the-universe-what-my-research-suggests-107922

I was about to post this as it appears Mike McCulloch has some serious competition. In my opinion, this is exactly the kinds of things McCulloch should be doing to bolster his theory.

Jamie Farnes is an established cosmologist at Oxford who took the time to base his theory in seemingly well-founded math and significant computational methods. He has some simulations with interesting results. 

He is able to show that his model creates dark matter halos, large-scale structure,  and he has observation time at the Square Kilometer Array (SKA) soon.  Here is his youtube channel:  {snip}



Beware of all these web media "discovering" this "new" and "revolutionary" theory (really just because of a PR issued by the University of Oxford and a subsequent article Farnes published in the Conversation on December 5, 2018) dismissing all other prior work about negative mass and negative energy states in quantum mechanics and cosmology.

Jamie Farnes' theory "unifying dark matter and dark energy as a repulsive dark fluid" is plagued by the theoretically unphysical and experimentally unobserved runaway motion effect arising in general relativity when one adds negative mass to the Einstein field equations, that Farnes yet embraces in his paper, writing:

Quote from: Jamie Farnes
[the runaway motion] behaviours violate no known physical laws. Negative masses are consistent with both conservation of momentum and conservation of energy.

Which is the same as saying that "perpetual motion does not violate conservation laws of physics". Indeed, it should be noted at first that as a couple (+m)(-m) indefinitely accelerates according to GR's runaway motion, it reaches a relativistic speed, but the total kinetic energy of the couple ˝(+m)v˛ + ˝(-m)v˛ stays constant… Moreover, there is an even more preposterous yet simpler explanation of such unphysical paradox. Astrophysicist Thomas Gold said, discussing Bondi's paper with Peter Bergmann, Felix Pirani and Dennis Sciama in 1957:

Quote from: Thomas Gold
What happens if one attaches a negative and positive mass pair to the rim of a wheel? This is incompatible with general relativity, for the device gets more massive.

As a consequence (but nobody seems to notice?) Farnes' model is an overunity theory.

EDIT: Comments from Sabine Hossenfelder about Farnes' theory. Hossenfelder is a physicist who published in Physical Review D a bimetric theory that also unifies dark matter and dark energy as one dark fluid, in 2008, ten years before Farnes (yet today ignored by memorylessness media). See also her 2009 presentation paper. She was the first to publish a Lagrangian derivation of a system of two coupled field equations managing positive and negative masses in cosmology with no runaway paradox, in a very similar way to the Janus cosmological model, which uses about the same sets of equations (except various additional "pull-overs" in Hossenfelder's theory).
« Last Edit: 12/10/2018 01:31 pm by flux_capacitor »

Offline Monomorphic

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As a consequence (but nobody seems to notice?) Farnes' model is an overunity theory.

EDIT: Comments from Sabine Hossenfelder about Farnes' theory. Hossenfelder is a physicist who published in Physical Review D a bimetric theory that also unifies dark matter and dark energy as one dark fluid, in 2008, ten years before Farnes (yet today ignored by memorylessness media). See also her 2009 presentation paper. She was the first to publish a Lagrangian derivation of a system of two coupled field equations managing positive and negative masses in cosmology with no runaway paradox, in a very similar way to the Janus cosmological model, which uses about the same sets of equations (except various additional "pull-overs" in Hossenfelder's theory).

I am by no means a proponent of the theory and would not want to die on this hill, but I thought this point was covered by Farnes in the paper here, which you partially quoted:

"One of the more bizarre properties of negative mass is that which occurs in positive–negative mass particle pairs. If both masses have equal magnitude, then the particles undergo a process of runaway motion. The net mass of the particle pair is equal to zero. Consequently, the pair can eventually accelerate to a speed equal to the speed of light, c. Due to the vanishing mass, such motion is strongly subject to Brownian motion from interactions
with other particles. In the alternative cases where both masses have unequal magnitudes, then either the positive or the negative mass may outpace the other – resulting in either a collision or the end of the interaction.
Although counterintuitive and “preposterous” (Bonnor 1989), all of these behaviours violate no known physical laws. Negative masses are consistent with both conservation of momentum and conservation of energy (Forward 1990), and have been shown to be fully consistent with general relativity in the seminal work of Bondi (1957)."




As for Hossenfelder's comments on Farnes' theory, Farnes responded in the comments with this:

"Jamie Farnes submits the following comment:

"Thank you for writing an article about this. However, I do not think these comments are actually related to the findings in my paper, but rather the papers of others. Your disagreement appears to be with the work of Bondi, who showed that these negative masses are compatible with GR. The comments seem to ignore Bondi's seminal work. I highlight in my paper that spin-2 particles are not at all relevant in this model - I know that is the lens through which you view these equations, but it is just one of many perspectives.

There also seems to be some confusion about section 2.3.3. and the “counterintuitive” finding. This is not actually related to my own work, but is actually an outcome from the cited work of Stephen Hawking and Don Page. It's not counterintuitive because it is wrong, just because that is how the predicted universe would behave!

So the article in its current form gives the impression that it disagrees with my paper, but you are actually disagreeing with far more influential works and authors.

A creation term is also not a "magic fix by which you can explain everything and anything". That is incredibly misleading. It provides very exact and specific well-defined physical properties.

The article also currently reads: "The primary reason that we use dark matter and dark energy to explain cosmological observations is that they are simple." Here you are neglecting the fact that there is ***no physical explanation*** for either dark energy and dark matter. My theory provides the first physical explanation for both of these phenomena in a single unified and intuitive framework. Given the lack of evidence for all conventional theories at present, including those which you frequently highlight, I am surprised that you would not see the advantage to a new idea.

Highlighting the vacuum instability is also completely wrong. This is a feature of the theory, and this is clearly emphasised in the paper. The creation term moderates the production rate of negative mass particles, and prevents this from being a catastrophic event.

Having said all that, I do greatly appreciate the last paragraph, which I think is much more correct. The article also does not mention the abundance of astrophysical observations which my model seems to match - I think to present it as a theory is not really fair or accurate, given the initial matching to the real world."
« Last Edit: 12/10/2018 09:11 pm by Monomorphic »

Offline TheTraveller

Enjoy the latest www.emdrive.com news

Quote
December 2018

A short Technical Note on Thrust performance versus Load conditions of EmDrive Thrusters is given here.

The note explains why EmDrive complies with both the Law of Conservation of Momentum, as well as the Law of Conservation of Energy.

Technical Note on Emdrive Thrust v Load
http://www.emdrive.com/thrustvload.pdf
« Last Edit: 12/11/2018 02:23 am by TheTraveller »
It Is Time For The EmDrive To Come Out Of The Shadows

Offline meberbs

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Enjoy the latest www.emdrive.com news

Quote
December 2018

A short Technical Note on Thrust performance versus Load conditions of EmDrive Thrusters is given here.

The note explains why EmDrive complies with both the Law of Conservation of Momentum, as well as the Law of Conservation of Energy.

Technical Note on Emdrive Thrust v Load
http://www.emdrive.com/thrustvload.pdf
Anyone actually need a detailed explanation of how everything in the provided link is nothing but gibberish?

Offline TheTraveller

Enjoy the latest www.emdrive.com news

Quote
December 2018

A short Technical Note on Thrust performance versus Load conditions of EmDrive Thrusters is given here.

The note explains why EmDrive complies with both the Law of Conservation of Momentum, as well as the Law of Conservation of Energy.

Technical Note on Emdrive Thrust v Load
http://www.emdrive.com/thrustvload.pdf
Anyone actually need a detailed explanation of how everything in the provided link is nothing but gibberish?

Meberbs,

Please note that in 2006 the Demonstrator EmDrive had a 8.2g frictional load applied while it accelerated on the rotary test rig.

Quote
The rotary air bearing supports a total load of 100kg, with a friction torque resulting in a calibrated resistance force of 8.2 gm at the engine centre of thrust.

http://emdrive.com/dynamictests.html

Might ask yourself why the frictional load was required?
It Is Time For The EmDrive To Come Out Of The Shadows

Offline Flyby

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TT,  I don't think we need more additional papers on how it "supposedly" would work, but more videos and factual proof of WORKING EM drives...

Less words, more proof...to put it bluntly...

Offline OnlyMe

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...
There was never any practical evidence in the early tests and data that supports scalability. Nothing to say that a larger or smaller frustum, functioning at higher or lower frequencies or power levels, would produce similar results. A great deal of speculation, but data?

I don’t know if there is any practical potential in the EmDrive concept. At the same time I don’t believe that any test data in the public domain proves that there is no practical potential. Even a few ounces of propellant less thrust, could revolutionize the space industry from low earth orbit on...
The problem with "proves that there is no practical potential" is the typical problem with proving a negative. There is always going to be some other variable or combination that hasn't been tested. This is why I think it is important to set some kind of defined boundaries for when to call it a dead end.

At this point with the available data, there is certainly some additional final testing that can reasonably be done, as there are a few ongoing experiments that haven't been finalized. But given that there is little in potentially positive data that hasn't been countered with more sensitive experiments I am not sure how much more is reasonable. It is also useful to keep in mind that electrodynamics really has been well tested in a wide range of regimes, spanning everything that occurs in an emDrive. This is why from the beginning it was just short of certain that the data that showed thrust was nothing other than experimental errors.

As to your suggestion for higher power tests, there were issues with magnetrons, and their poor frequency stability, which is a problem for matching good resonance, it could be done, but despite the lower total power, more recent tests have been more sensitive in a force/power ratio sense. I am not going to tell anyone not to run an experiment (unless there are clear flaws that would make the experiment useless), I would just suggest defining in a precise sense what "good enough" means for what testing you want to do. (Even if you aren't planning on funding or doing more testing yourself, you can still state your opinion on what you think is worthwhile.)

meberbs,

The word “proves” is itself subjective, and yet does tend toward an more rigid interpretation. To avoid a discussion of semantics, just replace it with “demonstrates”. In context they mean the same thing, while demonstrates does not insist on the same absolute interpretation. You know that there have been and will continue to be both theoretical and experimental proofs, that are later falsified. I never intended the more rigid interpretation of the word.

Beyond that, I believe my intention should have been clear. If you begin with a design that produces even questionable positive results, in this case a frustum with an adjustable small end and powered by a magnetron, you cannot clarify those questionable results, including the even unlikely possibility of an anomalous force, by preforming the experiment with a substantially different design. Redesign the testbed and retest the original build.

I had hopes that SeeShells’ build from late 2015 might have been repaired and tested on a testbed capable of addressing some of the concerns raised. It seems she had cleaned up the magnetron frequency stability and retained some of the early design characteristics...

Without beginning with a build that has generated even a questionable positive result, you cannot know that the design changes have not designed out the potential.

There is no way to know that matching resonance is the key. It very well could be that the instability of the magnetron is important or even that whatever might have been happening is subject to a minimum power threshold. There has not been enough testing in the public realm to know., one way or the other. It seems that each time a design has been tested with questionable results, both the build and testbeds have been redesigned. That was true even with professor Yang’s two published examples... two substantially different builds tested on two substantially different testbeds.

It seems that even Eagleworks early intent was to build a device test it and then provide that same device/build to another lab to be retested. I would like to have seen that kind of experimental rigor followed with a magnetron powered early frustum design... demonstrate some repeatability, before beginning to refine and experiment with fundamental design changes.


Offline OnlyMe

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Enjoy the latest www.emdrive.com news

Quote
December 2018

A short Technical Note on Thrust performance versus Load conditions of EmDrive Thrusters is given here.

The note explains why EmDrive complies with both the Law of Conservation of Momentum, as well as the Law of Conservation of Energy.

Technical Note on Emdrive Thrust v Load
http://www.emdrive.com/thrustvload.pdf
Anyone actually need a detailed explanation of how everything in the provided link is nothing but gibberish?

Meberbs,

Please note that in 2006 the Demonstrator EmDrive had a 8.2g frictional load applied while it accelerated on the rotary test rig.

Quote
The rotary air bearing supports a total load of 100kg, with a friction torque resulting in a calibrated resistance force of 8.2 gm at the engine centre of thrust.

http://emdrive.com/dynamictests.html

Might ask yourself why the frictional load was required?

TT,

Your comment implies that without that load the rotary rig was frictionless and does not address the past unanswered criticisms, questioning the affect of coolant flow and pump operation, among other design issues, suggested by the photos.

BTW where is that rotary rig now? If it really worked it would have been worth a pretty penny then, let alone today.

Offline meberbs

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Meberbs,

Please note that in 2006 the Demonstrator EmDrive had a 8.2g frictional load applied while it accelerated on the rotary test rig.

Quote
The rotary air bearing supports a total load of 100kg, with a friction torque resulting in a calibrated resistance force of 8.2 gm at the engine centre of thrust.

http://emdrive.com/dynamictests.html

Might ask yourself why the frictional load was required?
Others have already explained other problems with that experiment, and in no way can you claim that the friction was "required" (That would require removing all other error sources, and more tests showing that it only works with friction present)

The paper is obviously wrong in many ways, and it has already been explained to you repeatedly that a device that accelerates free space without interacting with anything outside of itself (i.e. something not accelerating with it) is the definition of violating conservation of momentum. The paper ignores this entirely.

Also, the explanation for the first row of the table is yet again Shawyer using reaction force as a term he just inserts wherever he finds in convenient, ignoring the actual definition. In reality if the emDrive was actually generating a force, the readout of the scale would reduce, because the scale measures only the force pushing down on it, which is just the portion of the weight of the object not cancelled by the magical upwards force generated by the emDrive.

If you consider what happens when transitioning from row 3 to row 2 of the table, Shawyer is claiming that adding an additional mass on top that creates an additional downwards force, with no effect on the internals of the emDrive, he even assumes that motion of the scale surface downwards is ideally 0, suddenly makes the drive jump upwards.

The only thing the paper shows is actually a bunch of handwaving that Shawyer can use to reject any experiment he doesn't like the results of given the logical inconsistency of his claims. Whether this is due to willful ignorance or deliberate deception on his part is the only question, but I decline to speculate on this.

Offline flux_capacitor

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As a consequence (but nobody seems to notice?) Farnes' model is an overunity theory.

EDIT: Comments from Sabine Hossenfelder about Farnes' theory. Hossenfelder is a physicist who published in Physical Review D a bimetric theory that also unifies dark matter and dark energy as one dark fluid, in 2008, ten years before Farnes (yet today ignored by memorylessness media). See also her 2009 presentation paper. She was the first to publish a Lagrangian derivation of a system of two coupled field equations managing positive and negative masses in cosmology with no runaway paradox, in a very similar way to the Janus cosmological model, which uses about the same sets of equations (except various additional "pull-overs" in Hossenfelder's theory).

I am by no means a proponent of the theory and would not want to die on this hill, but I thought this point was covered by Farnes in the paper here, which you partially quoted:

{extensive quotes of Hossenfelder and Farnes}

Yes I understand you're not a proponent of that theory, you're just like me and others here interested in such questions about negative energy states.

The simple fact is: Farnes dodges this question. Because the simple answer is: Farnes uses a negative gravitational mass AND a negative inertial mass in his theory for his negative mass (or "dark fluid" as he calls it). All the issue boils down to that simple axiom.

Why? In his answer to Hossenfelder, he tries to toss the hot potato to Hermann Bondi, saying that all these questions are rather related to the work of others and not his own work, but in fact Bondi justly covered all possibilities including the one chosen by Farnes, that is:
  gravitational mass = inertial mass for each kind of particles
+ both positive and negative mass particles share the same family of geodesics (from the same metric gμν in the Einstein field equations)

which corresponds to Bondi's hypothesis (iv) in his 1957 paper.

This arbitrary choice seems at first handy and elegant as it naturally satisfies Einstein's equivalence principle, but as noted by Hossenfelder this leads to catastrophic behaviors in real examples. One can try to reduce the problem talking of "Brownian motion for interactions with other particles" as Farnes does in his paper, as well as resorting to different mass values for a couple (+m)(-m) which fortunately prevent in this case such pair to accelerate indefinitely in a runaway motion. But the true fact is, according to these fundamental hypotheses, if one attaches Farnes' negative mass next to a positive mass (of the same amount |m | ) on a wheel, it accelerates as a perpetual motion and "gets more massive" which is incompatible with general relativity, as noted by Gold. For me, this is a much more simple yet bigger problem than all other peripheral things Farnes acknowledged to discuss.


Bondi's hypothesis (iii) does not violate the EEP if two metrics (two distinct families of geodesics) are considered, one for positive energy species and a second one for negative energy species. Two metrics for a single manifold, a frontside and a backside on the same 4D hypersurface describing the universe.

This is the path independently followed by S. Hossenfelder and J.P. Petit. In such a case, the "negativity" of some mass is not an intrinsic physical feature, it arises instead from the geometry of spacetime itself, from its local amount of curvature.

According to these two authors, some negative curvature that would be measured somewhere in spacetime (Look! A Negative Mass!) introduces a new concept of apparent mass. EVERY single inertial mass is always positive, for any massive particle in the whole universe. But from a different perspective, from the point of view of its own metric or as measured from the opposite one (from the "backside" of the hypersurface) the gravitational mass of that particle appears positive or negative, respectively. This geometric concept of "conjugate curvatures" is still absolutely not understood (or at least absolutely not discussed).

Incidentally, bimetric models also explains why negative mass (= dark matter) remains optically invisible, a feature unexplainable in single-metric models like Farnes' theory.

All this to set the pendulum back on a more neutral position ;) It's good to finally hear about theories introducing negative mass in cosmology, but it doesn't hurt to talk about all valid theories, especially when some prior work do exist in parallel to an undue biased buzz by the media.
« Last Edit: 12/11/2018 06:23 pm by flux_capacitor »

Offline flux_capacitor

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Also, the explanation for the first row of the table is yet again Shawyer using reaction force as a term he just inserts wherever he finds in convenient, ignoring the actual definition. In reality if the emDrive was actually generating a force, the readout of the scale would reduce, because the scale measures only the force pushing down on it, which is just the portion of the weight of the object not cancelled by the magical upwards force generated by the emDrive.

Agreed. Let's say otherwise it the simplest way possible. This would work if the EmDrive was a rocket expelling matter (hot gas) backward behind its nozzle, but the EmDrive has no exhaust and does not expel ANYTHING. So if it worked as a genuine propellantless thruster, it would be rather like an aerostat or a warp drive. TT: if you have a 800-pound gorilla sitting in a room on a scale, the scale reads 800 pounds, OK? Now suppose you have a big helium balloon able to lift a mass of exactly 400 pounds. Being kind with him, you attach your balloon to the gorilla. What is the result? The gorilla does not lift in the air, for the ballon does not apply enough force upward to counteract gravity. But according to 1st row of table 1, Shawyer says the scale still reads 800 pounds. This is wrong: it now reads 400 pounds.

Online Chris Bergin

Whoa. You can be critical about published work, but you can't attack another member for it. That's' where we step in.
One post deleted, posting the above to warn people "not to go there" as I know a lot of you are in this EM Drive bubble and forget the forum rules apply even in this wacky backwater. ;)
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Offline Monomorphic

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But the true fact is, according to these fundamental hypotheses, if one attaches Farnes' negative mass next to a positive mass (of the same amount |m | ) on a wheel, it accelerates as a perpetual motion and "gets more massive" which is incompatible with general relativity, as noted by Gold.

I played around with these kinds of n-body toy universe models many years ago and one thing I noticed then was that it is fairly easy to simulate "structure formation"  - so perhaps that is the least impressive things his model mimics as far as I am concerned. It is also fairly subjective when describing tendrils, walls, voids, etc.

Farnes says the creation term is not a "magic fix," but it is simple to throw together a toy universe model that shows structure formation when using a similar creation metric. In the model below,  I am simulating 5,000 particles of positive mass, but with a creation metric similar to Farnes' creation tensor for the negative mass particles.   

I noticed that creating particles randomly out of nowhere helps smooth out the results of the model. This definitely helps improve structure formation (such as tendrils) - so it is kind of a magic fix.   




« Last Edit: 12/12/2018 02:57 am by Monomorphic »

Offline TheTraveller

Also, the explanation for the first row of the table is yet again Shawyer using reaction force as a term he just inserts wherever he finds in convenient, ignoring the actual definition. In reality if the emDrive was actually generating a force, the readout of the scale would reduce, because the scale measures only the force pushing down on it, which is just the portion of the weight of the object not cancelled by the magical upwards force generated by the emDrive.

Agreed. Let's say otherwise it the simplest way possible. This would work if the EmDrive was a rocket expelling matter (hot gas) backward behind its nozzle, but the EmDrive has no exhaust and does not expel ANYTHING. So if it worked as a genuine propellantless thruster, it would be rather like an aerostat or a warp drive. TT: if you have a 800-pound gorilla sitting in a room on a scale, the scale reads 800 pounds, OK? Now suppose you have a big helium balloon able to lift a mass of exactly 400 pounds. Being kind with him, you attach your balloon to the gorilla. What is the result? The gorilla does not lift in the air, for the ballon does not apply enough force upward to counteract gravity. But according to 1st row of table 1, Shawyer says the scale still reads 800 pounds. This is wrong: it now reads 400 pounds.

Hi FC,

In example 1, as per Roger's assumptions, the EmDrive can't move / accelerate so there is no force generated, being F = ma, and the result is correct. This has been the case since day one.

Yes in reality the scale does move down slightly to record the 2g added mass and thus a 1g upward force from the EmDrive will cause a very small upward acceleration and a reduction in the displayed mass. However it is no way as simple as either case given here nor are the effects linear at the start of acceleration plus the thrust will stop when the EmDrive has moved upward as far as it can and acceleration stops.

All of this has been gone over many times, so nothing new here.
It Is Time For The EmDrive To Come Out Of The Shadows

Offline meberbs

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In example 1, as per Roger's assumptions, the EmDrive can't move / accelerate so there is no force generated, being F = ma, and the result is correct. This has been the case since day one.
As anyone who has taken introductory physics knows, the F in that equation is the sum of all forces on an object.

For Shawyer's example, there is the force of the balance beam which is equal and opposite to the force of gravity on the drive, there is the force of the mass pushing the drive down, there is the force of the scale keeping the drive from moving downwards (which is what the readout of the scale reports) and there is the magic upwards force produced by the drive (or the 400lb upwards force of the balloon in flux_capacitor's example.) There being no acceleration just means that these forces are balanced. It does not make any of them zero. By the logic in your statement, the scale reading would not change when the balloon is attached to the gorilla, which is simply wrong.

Yes in reality the scale does move down slightly to record the 2g added mass and thus a 1g upward force from the EmDrive will cause a very small upward acceleration and a reduction in the displayed mass. However it is no way as simple as either case given here nor are the effects linear at the start of acceleration plus the thrust will stop when the EmDrive has moved upward as far as it can and acceleration stops.
Nope, Shawyer claims none of this. Statements about nonlinearities, or necessity of freedom for downwards motion (when any motion would be upwards anyway)  irrelevant.

All of this has been gone over many times, so nothing new here.
Yet you still deny that Shawyer is failing introductory level physics, and simply ignore things like the obvious incongruity moving from line 3 to line 2 of the table Shawyer wrote that I pointed out.

Offline TheTraveller

In example 1, as per Roger's assumptions, the EmDrive can't move / accelerate so there is no force generated, being F = ma, and the result is correct. This has been the case since day one.
As anyone who has taken introductory physics knows, the F in that equation is the sum of all forces on an object.

For Shawyer's example, there is the force of the balance beam which is equal and opposite to the force of gravity on the drive, there is the force of the mass pushing the drive down, there is the force of the scale keeping the drive from moving downwards (which is what the readout of the scale reports) and there is the magic upwards force produced by the drive (or the 400lb upwards force of the balloon in flux_capacitor's example.) There being no acceleration just means that these forces are balanced. It does not make any of them zero. By the logic in your statement, the scale reading would not change when the balloon is attached to the gorilla, which is simply wrong.

Yes in reality the scale does move down slightly to record the 2g added mass and thus a 1g upward force from the EmDrive will cause a very small upward acceleration and a reduction in the displayed mass. However it is no way as simple as either case given here nor are the effects linear at the start of acceleration plus the thrust will stop when the EmDrive has moved upward as far as it can and acceleration stops.
Nope, Shawyer claims none of this. Statements about nonlinearities, or necessity of freedom for downwards motion (when any motion would be upwards anyway)  irrelevant.

All of this has been gone over many times, so nothing new here.
Yet you still deny that Shawyer is failing introductory level physics, and simply ignore things like the obvious incongruity moving from line 3 to line 2 of the table Shawyer wrote that I pointed out.


Meberbs,

As has been stated from day one, if an EmDrive can't accelerate, as in example one, there is no force generated. Ie if a = 0 then F = ma = 0.

Using an example of a helium filled balloon, which generates upward force even if not accelerating, is clearly not a valid argument to use with example 1.
It Is Time For The EmDrive To Come Out Of The Shadows

Offline meberbs

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Meberbs,

As has been stated from day one, if an EmDrive can't accelerate, as in example one, there is no force generated. Ie if a = 0 then F = ma = 0.

Using an example of a helium filled balloon, which generates upward force even if not accelerating, is clearly not a valid argument to use with example 1.
As has been explained to you countless times the "can't accelerate" condition makes no sense. As I literally just explained, F =ma means something different. F =ma applies just as much to the balloon as it does to the emDrive. If you base your argument on that, you are clearly wrong. There is no way for the electrodynamic forces to know the difference between the situations described in Shawyer's paper and change whether they are producing a net force. Plus what you are saying continues to ignore the other examples, such as the second one where a net deflection happens, and the emDrive remains deflected despite the no motion in the lab frame. Plus in the third one, it is more free to accelerate, but doesn't move for no reason whatsoever.

Also you are still ignoring that as far as the effect on emWaves inside the cavity is concerned, pointing upwards in a gravity well is equivalent to accelerating at 1 g. The force is either there or it isn't. Claiming that it comes and goes based on factors that don't have any way to effect the electrodynamic forces makes no sense.

Offline OnlyMe

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Enjoy the latest www.emdrive.com news

Quote
December 2018

A short Technical Note on Thrust performance versus Load conditions of EmDrive Thrusters is given here.

The note explains why EmDrive complies with both the Law of Conservation of Momentum, as well as the Law of Conservation of Energy.

Technical Note on Emdrive Thrust v Load
http://www.emdrive.com/thrustvload.pdf

TT,

Most of your argument just doesn’t make sense. Still a single sentence from early in the link above seems to suggest I have missed something very important... These have been repeatedly observed during experimental work extending over many years, and under many different test conditions, including reports of in orbit tests.

Where is the data from these, “…in orbit tests.”?

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