Where is the paper? Is it possible to download a copy from somewhere?
Where is the paper? Is it possible to download a copy from somewhere?
It's not published until December.
ah...thought the traveller said it was in circulation. does that just mean in academic circles?
ah...thought the traveller said it was in circulation. does that just mean in academic circles?
Since it has been peer reviewed, the reviewers will have seen it, plus probably some other distribution within NASA.
Contrary to TT's comment, I do not believe it is common for papers to leak before publication. Most reviewers have at least that much integrity, and it would not be enough people involved that the odds of a bad apple would be particularly high.
Here is a thought. Let's measure the power in through the antenna. Doing so we should know the amount of heat that should be present in the frustum. Immerse the thing in a substance that has heat capacity and run it over a period of time. Later we measure the temperature and we get the time accumulated energy dumped into heat.
If there is any work being done on something that is escaping the frustum, then some of that energy will be lost and not show up as heat. We would have some discrepancy in the energy put in and the heat generated? Bad or good idea?
Another test is to completely enclose the device and put it into a neutral buoyancy tank. Also, short of space itself, one could set up some tests in zero gee with the vomit comet. Net thrust ought to be evident over the thirty second or so zero gee phase.
Here is a thought. Let's measure the power in through the antenna. Doing so we should know the amount of heat that should be present in the frustum. Immerse the thing in a substance that has heat capacity and run it over a period of time. Later we measure the temperature and we get the time accumulated energy dumped into heat.
If there is any work being done on something that is escaping the frustum, then some of that energy will be lost and not show up as heat. We would have some discrepancy in the energy put in and the heat generated? Bad or good idea?
Another test is to completely enclose the device and put it into a neutral buoyancy tank. Also, short of space itself, one could set up some tests in zero gee with the vomit comet. Net thrust ought to be evident over the thirty second or so zero gee phase.
neutral buoyancy could still be effected by thermal gradients. Zero gee in the vomit comet I think has been mentioned before by someone I think but you would be limited on time and costs but maybe. You might still have the problem of thermal gradients in the vomit comet also.
The idea of just measuring the power put in and the increase in heat is to eliminate force measurements plagued by other effects and look for thermal anomalies. If something is escaping the cavity and carrying away momentum it should show up as missing energy.
I came across a treasure-trove of magnetrons at an electronics flea market yesterday. I didn't buy them.
Thermal buoyancy could still be effected by thermal gradients. Zero gee in the vomit comet I think has been mentioned before by someone I think but you would be limited on time and costs but maybe. You might still have the problem of thermal gradients in the vomit comet also.
The idea of just measuring the power put in and the increase in heat is to eliminate force measurements plagued by other effects and look for thermal anomalies. If something is escaping the cavity and carrying away momentum it should show up as missing energy.
Forgot to mention just floating the device in a large controlled enclosed space with helium balloons or configured as a mini Zeppelin. If accelerations of at least 0.01 m/s2 could be achieved it would be pretty clear it works.
ah...thought the traveller said it was in circulation. does that just mean in academic circles?
Since it has been peer reviewed, the reviewers will have seen it, plus probably some other distribution within NASA.
Contrary to TT's comment, I do not believe it is common for papers to leak before publication. Most reviewers have at least that much integrity, and it would not be enough people involved that the odds of a bad apple would be particularly high.
mmmm, for once I agree with TT (but don't get used to that!)
Unless a paper is really controversial (like this might be the case) or it contains very sensitive information (again, this might be the case) it's rather common practice among scholars to circulate their papers in their circles, usually even before submitting, precisely to have a better grasp of the (informed) public's reaction.
Myself (a scholar in a completely different field) I always circulate my working papers well before they even go to review to get comments & suggestions back.
ah...thought the traveller said it was in circulation. does that just mean in academic circles?
Since it has been peer reviewed, the reviewers will have seen it, plus probably some other distribution within NASA.
Contrary to TT's comment, I do not believe it is common for papers to leak before publication. Most reviewers have at least that much integrity, and it would not be enough people involved that the odds of a bad apple would be particularly high.
mmmm, for once I agree with TT (but don't get used to that!)
Unless a paper is really controversial (like this might be the case) or it contains very sensitive information (again, this might be the case) it's rather common practice among scholars to circulate their papers in their circles, usually even before submitting, precisely to have a better grasp of the (informed) public's reaction.
Myself (a scholar in a completely different field) I always circulate my working papers well before they even go to review to get comments & suggestions back.
You've laid out two very good reasons this paper may not have been circulated far.
Does anyone have any recent information on the laser interferometer ("warp field") experiments at Eagleworks, related to the EM Drive?
I hear quite a bit about it last year but not since...
A lot of physics could be extracted by further
analysis of this perturbation equations in different situations that at present can be
managed only numerically.
The special case of four dimensions implies that, being the energy-momentum tensor
of the electromagnetic field traceless, the scalar field does not couple directly with the
electromagnetic field
I'm not going to pretend that I really understand the passages I quote above. Rather, I ask those that do understand them...
Would Frasca's Brans-Dicke model for EM Drive operation make any other easily testable predictions? Any chance a theory like this could account for flyby anomalies?
A lot of physics could be extracted by further
analysis of this perturbation equations in different situations that at present can be
managed only numerically.
The special case of four dimensions implies that, being the energy-momentum tensor
of the electromagnetic field traceless, the scalar field does not couple directly with the
electromagnetic field
I'm not going to pretend that I really understand the passages I quote above. Rather, I ask those that do understand them...
Would Frasca's Brans-Dicke model for EM Drive operation make any other easily testable predictions? Any chance a theory like this could account for flyby anomalies?
The first quote just points out that the equations we have to cope with are too much complicated that, to solve them, generally a computer is needed. This is an ongoing activity with a lot of interesting results so far. But you can fix any geometry, like that of a frustum, and you will get a general solution by putting all the data into a machine and let it crunch them. Anyhow, in the case at hand, some simple approximations can help to avoid to use a computer and get some useful equation to understand what is going on.
The second quote just states that the gravitational constant, that in Brans-Dicke model is not really a constant, can change inside the frustum in a significant way. This can only happen through the square of the energy density of the e.m. field by an indirect coupling with the warped space-time inside the truncated cone because the effect of the e.m. field is not a direct one on the gravitational constant.
Testable predictions can be extended to laser interferometry, an ongoing activity at EW labs, but, having a complete theory, you can think to build any setup and compute the expected effects.
I would like to emphasize that, if it is confirmed that Brans-Dicke model is at work inside the frustum, this would be already a breakthrough in physics.
The second quote just states that the gravitational constant, that in Brans-Dicke model is not really a constant, can change inside the frustum in a significant way. This can only happen through the square of the energy density of the e.m. field by an indirect coupling with the warped space-time inside the truncated cone because the effect of the e.m. field is not a direct one on the gravitational constant.
Testable predictions can be extended to laser interferometry, an ongoing activity at EW labs, but, having a complete theory, you can think to build any setup and compute the expected effects.
I would like to emphasize that, if it is confirmed that Brans-Dicke model is at work inside the frustum, this would be already a breakthrough in physics.
Marco, I have three questions:
1/ Can you explain in layman terms how his your Brans-Dicke theory different from
Minotti's who also explains the anomalous thrust of asymmetric EM resonators?
2/ Does your development of the Brans-Dicke theory predict if a powerful and efficient (superconducting or not) asymmetric RF resonant cavity, or array of cavities, can achieve enough thrust to lift a body within Earth gravitational field (aka lift engine) or does the predicted thrust/weight ratio is always tiny, containing the space flight applications to deep space probes only?
3/ EmDrive apart, if the effect can scale up at the square of the energy density of the EM field and hence can truly alter some physical constants, do you think a huge amount of concentrated energy could warp spacetime enough so it could locally go beyond neutrons' critical density threshold and create a mini black hole?
...
Marco, I have three questions:
1/ Can you explain in layman terms how his your Brans-Dicke theory different from Minotti's who also explains the anomalous thrust of asymmetric EM resonators?
2/ Does your development of the Brans-Dicke theory predict if a powerful and efficient (superconducting or not) asymmetric RF resonant cavity, or array of cavities, can achieve enough thrust to lift a body within Earth gravitational field (aka lift engine) or does the predicted thrust/weight ratio is always tiny, containing the space flight applications to deep space probes only?
3/ EmDrive apart, if the effect can scale up at the square of the energy density of the EM field and hence can truly alter some physical constants, do you think a huge amount of concentrated energy could warp spacetime enough so it could locally go beyond neutrons' critical density threshold and create a mini black hole?
1) Differently form Minotti's approach, Brans-Dicke theory (it is not mine) is a model accepted by the community since '60s. It has been a workhorse to unveil possible deviations from general relativity. It introduces a set of constants, the most important is omega, that provide an understanding about how Einstein's equations could change. For these reasons, it has been and is today an accepted theory by all the scientific community. What it is seen is that the agreement between Einstein's theory and Brans-Dicke theory is perfect provided the omega parameter is taken large enough. So, this for the cosmological and planetary scales. But, inside a resonant cavity, with a large e.m. field, things could be quite different as I show. Particularly, Newton constant could become quite large due the square of the energy density of the e.m. field inside. This kind of physical setup has not been analyzed before for Brans-Dicke theory and the results appear to be absolutely striking.
2) Now, one has formulas to project an optimized cavity to take thrust to its maximum from a physical standpoint. For a superconducting cavity what really matters is the Q factor and this largely increases thrust. This is all due to Einstein's theory of general relativity with the proper correction arising from Brans-Dicke model (just a change in the Newton constant). This change should be computed in the design phase.
3) No, I fear this is impossible.
Now, one has formulas to project an optimized cavity to take thrust to its maximum from a physical standpoint. For a superconducting cavity what really matters is the Q factor and this largely increases thrust. This is all due to Einstein's theory of general relativity with the proper correction arising from Brans-Dicke model (just a change in the Newton constant). This change should be computed in the design phase.
So, a resonating symmetrical cavity with high Q factor, due to the highly concentrated EM field, will alter the gravitational constant (and be testable using laser interferometry), but will not produce any thrust because this alteration is symmetrical in relation to the cavity's center of mass?
The thrust is generated because of the asymmetrically offset alteration of the gravitational constant in relation to the cavity's center of mass? Hence, the greater the offset achieved (TE212 vs TE013 for instance), the greater the thrust measured (assuming the same Q value)?
For these reasons, it has been and is today an accepted theory by all the scientific community. What it is seen is that the agreement between Einstein's theory and Brans-Dicke theory is perfect provided the omega parameter is taken large enough. So, this for the cosmological and planetary scales. But, inside a resonant cavity, with a large e.m. field, things could be quite different as I show.
Playing devil's advocate, the point of a locally varying constant in Brans-Dicke theory reminds me of a skeptical discussion I followed some time ago on another forum about Brans' view in 1962 (and what is understood nowadays from his view) stating that gravitational potential energy-momentum is not locally defined in Einstein's GR, because the Einstein stress-energy pseudotensor is not a covariant quantity, hence that
no meaningful covariant values can be assigned locally to this quantity. That would be the main issue for the local aspects of Brans-Dicke theory related to the EmDrive.
But trying to avoid comparing apples and oranges leads to how φ is defined respectively in the Brans-Dicke theory, and Einstein's general theory of relativity. In
The Meaning of Relativity, discussing 1916 GR, Einstein was talking specifically about g
tt/2 as the GR version of the Newtonian potential φ. But Brans-Dicke φ is an invariant scalar field, unlike g
tt(
x), and not Einstein's own original φ as per his earliest attempts at a relativistic theory of gravity. Can you clarify this point?
...
So, a resonating symmetrical cavity with high Q factor, due to the highly concentrated EM field, will alter the gravitational constant (and be testable using laser interferometry), but will not produce any thrust because this alteration is symmetrical in relation to the cavity's center of mass?
The thrust is generated because of the asymmetrically offset alteration of the gravitational constant in relation to the cavity's center of mass? Hence, the greater the offset achieved (TE212 vs TE013 for instance), the greater the thrust measured (assuming the same Q value)?
This was already discussed with Dr. Rodal. Newton constant does not count in this case. All you need is an asymmetry. With the original computation, you needed practically a cone to get a tiny effect. Here, due to the change in the Newton constant, the need for a conical cavity can be dismissed.