Dr. Rodal,
I'm not quite sure I'm following this correctly, but, are you basically saying that you are producing a region of reduced mass at one end of the device while increasing the mass at the other end of the device, or are we talking about what could be a region of expanded space behind the device and a compressed area in front?
If this is a negative or educed mass situation, should there not be a pressure change in the immediate area of the actual negative mass? If so, this should be measurable in the pressure of the air column directly beneath the area of negative mass, should it not?
None of that is discussed. The relativistic equations for conservation of momentum are posed, treating the EM Drive as a lumped mass system, and then seeing what a change in speed implies for the change in mass in order to satisfy conservation of momentum. For conservation of momentum, it doesn't matter how the negative mass was produced, it is assumed that it can be produced somehow, and the consequences are explored. It is shown that the laws of physics are not violated, within the range of variables explored in the note.
As to how one can have negative mass:
1) there has not been experimental confirmation of negative mass occurring naturally in the Universe and no experiments exist that have conclusively shown that negative mass can be produced artificially, to my knowledge.
2) Negative mass is a consistent theoretical concept that has been discussed by many physicists, most prominently starting with Bondi. Negative mass is allowed by the laws of physics.
3) As pointed out in my note, Minotti states that self-acceleration of the EM Drive if due to General Relativity theory with the scalar coupling field, implies negative mass. Lobo has discussed a number of other reaction-less propulsion that imply negative mass, and McCulloch's theory implies variable mass. Prof. Woodward's Mach Effect theory also discusses how negative mass can be produced. Ditto for Dr. White's theory.
So, I don't discuss how negative mass can be produced, but Minotti's paper gives a consistent theory of how a General Relativity theory with the scalar coupling field can indeed result in effective negative mass for the EM Drive.
Does it have to be negative mass? Could it be asymmetric mass instead (as determined by the frustum shape)? That would produce a falling effect as we feed energy into the system that would look like thrust to an outside observer. i.e. if you did this experiment with a tube, you'd get a spherical or tubular mass effect inside the cavity. With a frustum, you get a cone or teardrop shape.
If you re-distribute all the furniture inside the space station, to one corner of the space station, you will not produce self-acceleration of the space station.
You can re-distribute the mass inside the space station, or even throw it towards one corner so that it bounces off the walls and that still will not produce self-acceleration.
If I'm an observer inside of the space station with all the junk piled up into one side of the ISS, I'll feel the slight attraction of that mass. If I'm in orbit around another mass the more massive part of the station with the junk pilled into it will want to point in the direction of the mass. Correct?
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
Do you mean the center of force ? That can be separated from the center of mass.
Food for thought regarding gravity and photons...FWIW regarding emdrive discussions. There are some counterintuitive effects of gravity/mass (at least to me). Others might find this easily understood and I would be glad to hear about it.
Mass produces a gravity "well" or spacetime distortion the "sucks everything" towards it. Fair enough, seems logical. Then, we discover Gravitational Lensing:
https://en.wikipedia.org/wiki/Gravitational_lensTo me, this seems counterintuitive...photons directly behind an object and the observer not getting sucked in, but diverted around the object, appearing as a ring or distorted image (check out the images in the link).
Now, a "well" would seem to imply a photon or light source near an edge of an object in between an observer and source should bend photons TOWARDS the mass and be invisible to the observer...not distorted OUTWARDS and AROUND the object.
I am sure I am missing something here, but why do photons
divert around rather than into the gravitational source of the interfering object?
...
I am sure I am missing something here, but why do photons divert around rather than into the gravitational source of the interfering object?
an object moving in space does not fall straight into a mass point but is subject to dynamical forces (due to the differential equations of motion) that govern its motion, usually as a conic section (and given enough speed it will elliptically orbit the object) including a hyperbolic trajectory
https://en.wikipedia.org/wiki/Orbital_mechanicsFortunately the Earth has been orbiting the sun long-enough for us humans to exist and to be able to able to figure this out
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
Do you mean the center of force ? That can be separated from the center of mass.
First, I have no formal education in physics. Physics is a hobby, something I spend a good deal of time thinking about and reading, but not something I know a ton about. When I think of gravity, I think of a single point which attracts the center of mass of near by objects. The object that forms the center of gravity is unaffected by the center of gravity because its center of mass is as close as it can get to the center of gravity already. I am talking about move the center of gravity of an object away from its center of mass
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
Do you mean the center of force ? That can be separated from the center of mass.
First, I have no formal education in physics. Physics is a hobby, something I spend a good deal of time thinking about and reading, but not something I know a ton about. When I think of gravity, I think of a single point which attracts the center of mass of near by objects. The object that forms the center of gravity is unaffected by the center of gravity because its center of mass is as close as it can get to the center of gravity already. I am talking about move the center of gravity of an object away from its center of mass
For the center of mass to be different from the center of gravity you would need to have non-uniform g over the body (perhaps because the body is huge). To a first approximation one considers the gravitational mass to be concentrated at a point and the attracted body's dimensions to be such that g is constant over the body so the center of mass ~ center of gravity.
Certainly for the purposes of this thread (EM Drive) you can safely assume that g is constant over the EM Drive' small dimensions.
New EMDrive Topic on NSF - Resonant Cavity Space Propulsion for Institutional Experiments and Theory
I've been meaning to alert our distinguished NSF emdrive readers & members that Dr Rodal has created a new emdrive thread specifically for Institutional Experimentation and Theory. This is a great way to expand the topic to a more specific audience. I expect this topic will continue to expand like this at NSF in the future. Doc changes the name a bit, more descriptive for a fresh audience.
I encourage all those involved with Institutions to bookmark this NSF topic to read and participate:
http://forum.nasaspaceflight.com/index.php?topic=39214.20Emdrive is growing here on NSF and this active main thread can be tedious to extract useful information,
especially for Colleges and Universities who are considering experimental or theoretical participation. Of course, this is still welcomed on the main thread, but users might find it easier to discuss more specific details there. I believe Doc welcomes all, but I think its designed for shakers and movers at individual Institutions.
Good luck Doc on the related thread...don't go anywhere. Keep us posted on the stuff happening there
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
Do you mean the center of force ? That can be separated from the center of mass.
First, I have no formal education in physics. Physics is a hobby, something I spend a good deal of time thinking about and reading, but not something I know a ton about. When I think of gravity, I think of a single point which attracts the center of mass of near by objects. The object that forms the center of gravity is unaffected by the center of gravity because its center of mass is as close as it can get to the center of gravity already. I am talking about move the center of gravity of an object away from its center of mass
For the center of mass to be different from the center of gravity you would need to have non-uniform g over the body (perhaps because the body is huge). To a first approximation one considers the gravitational mass to be concentrated at a point and the attracted body's dimensions to be such that g is constant over the body so the center of mass ~ center of gravity.
Certainly for the purposes of this thread (EM Drive) you can safely assume that g is constant over the EM Drive' small dimensions.
I agree that the relatively small mass of the EMdrive would have an equal CoG to CoM. My thought is, hypothetically, what would happen if an objects CoG wasn't equal to its CoM. And is it possible that the EMdrive is somehow displacing one of the two?
New EMDrive Topic on NSF - Resonant Cavity Space Propulsion for Institutional Experiments and Theory
I've been meaning to alert our distinguished NSF emdrive readers & members that Dr Rodal has created a new emdrive thread specifically for Institutional Experimentation and Theory. This is a great way to expand the topic to a more specific audience. I expect this topic continue to expand like this in the future. Doc changes the name a bit, more descriptive for a fresh audience.
I encourage all those involved with Institutions to bookmark this NSF topic to read and participate:
http://forum.nasaspaceflight.com/index.php?topic=39214.20
Emdrive is growing here on NSF and this active main thread can be tedious to extract useful information, especially for Colleges and Universities who are considering experimental or theoretical participation. Of course, this is still welcomed on the main thread, but users might find it easier to discuss more specific details there. I believe Doc welcomes all, but I think its designed for shakers and movers at individual Institutions.
Good luck Doc on the related thread...don't go anywhere. Keep us posted on the stuff happening there
Well thank you
The purpose of the different thread is to have a thread where one can easily find proofs, more formal discussion and factual data, since the EM Drive threads have become so huge
it is difficult for me to find things (I am guilty of posting too many comments on the EM Drive thread )
So, it is not meant as a competing thread but a small section for reference and discussion, just like we have the emdrive wiki for example
I thought about this a bit earlier, for me to understand it, I separated center of mass from center of gravity. In everyday life center of mass and center of gravity would coincide with each other since mass warps space to cause gravity. But what if you shifted the center of gravity away from the center of mass? Would it be like trying to pick yourself up? Or would you be falling toward your own gravitational center?
Do you mean the center of force ? That can be separated from the center of mass.
First, I have no formal education in physics. Physics is a hobby, something I spend a good deal of time thinking about and reading, but not something I know a ton about. When I think of gravity, I think of a single point which attracts the center of mass of near by objects. The object that forms the center of gravity is unaffected by the center of gravity because its center of mass is as close as it can get to the center of gravity already. I am talking about move the center of gravity of an object away from its center of mass
For the center of mass to be different from the center of gravity you would need to have non-uniform g over the body (perhaps because the body is huge). To a first approximation one considers the gravitational mass to be concentrated at a point and the attracted body's dimensions to be such that g is constant over the body so the center of mass ~ center of gravity.
Certainly for the purposes of this thread (EM Drive) you can safely assume that g is constant over the EM Drive' small dimensions.
I agree that the relatively small mass of the EMdrive would have an equal CoG to CoM. My thought is, hypothetically, what would happen if an objects CoG wasn't equal to its CoM. And is it possible that the EMdrive is somehow displacing one of the two?
It could happen when falling inside the horizon of a black hole. It would tear you apart
You know, asymmetrical resonant cavities might not have been proven to be useful thrusters yet (or ever) but they may have value as scientific instruments.
New EMDrive Topic on NSF - Resonant Cavity Space Propulsion for Institutional Experiments and Theory
I've been meaning to alert our distinguished NSF emdrive readers & members that Dr Rodal has created a new emdrive thread specifically for Institutional Experimentation and Theory. This is a great way to expand the topic to a more specific audience. I expect this topic continue to expand like this in the future. Doc changes the name a bit, more descriptive for a fresh audience.
I encourage all those involved with Institutions to bookmark this NSF topic to read and participate:
http://forum.nasaspaceflight.com/index.php?topic=39214.20
Emdrive is growing here on NSF and this active main thread can be tedious to extract useful information, especially for Colleges and Universities who are considering experimental or theoretical participation. Of course, this is still welcomed on the main thread, but users might find it easier to discuss more specific details there. I believe Doc welcomes all, but I think its designed for shakers and movers at individual Institutions.
Good luck Doc on the related thread...don't go anywhere. Keep us posted on the stuff happening there
Well thank you
The purpose of the different thread is to have a thread where one can easily find proofs, more formal discussion and factual data, since the EM Drive threads have become so huge it is difficult for me to find things (I am guilty of posting too many comments on the EM Drive thread )
So, it is not meant as a competing thread but a small section for reference and discussion, just like we have the emdrive wiki for example
Thanks a lot for citing my contribution in the new thread. Besides, that question without an answer by Harold White... We hope to hear something very soon from him.
...
I apparently genuinely mistook the following:
1) You need 2 plates to generate the Casimir force between them, one would need a plate in front of the spacecraft nanometers in front of it for the spacecraft to be attracted to it. A magnet in front of the spacecraft would generate a greater force and act at a greater distance
Apologies if I misread.
Yes, the above statement was made under the stated restriction of no external fields
Understanding now, I therefore deleted (in my prior post) the question of where that came from
Do you believe that a traveling wavefront in a cavity could have Casimir-effect inducing reflective properties? This is honestly just a thought I've toyed with.
Sorry, I don't know.
What seems evident to me is that either:
1) The reported anomalous forces are the result of experimental artifacts explainable by effects like thermal and electromagnetic effects not quantitatively taken into account.
or
2) The EM Drive is not a closed system, and the anomalous force can be explained as an open system (either by ejection of mass-energy or by coupling to external forces or fields). The problem here is that the reported forces are orders of magnitude greater than a perfect photon rocket.
or
3) The EM Drive anomalous force is due to coupling with General Relativity. This also appears to involve negative mass-energy, but I am not completely sure because the spacetime location of center of mass cannot be uniquely defined and because of the complications surrounding curved spacetime. The magnitude of the claimed force also appears to be a problem (as shown by Dr. Frasca and also by the fact that Minotti's theory would require an unexplored nonlinearity to reconcile with experimental measurements of the Universe).
or
4) The EM Drive is a closed system, in which case the only way I see to conserve momentum-energy for acceleration of the EM Drive is to have creation of negative mass-energy in the EM Drive
Your thoughts are compatible with #4 above
Dr. Rodal
It's such a simple thing.
Two large hollow balls with the centers of mass off center. The ball on the left, the mass is attached to the inside wall, the other ball a person floats with his mass in his head. The off centers of mass will rotate to align with each other. The human's head will start to rotate towards the other balls off mass center until he smacks his head into the wall of his ball.
The differences in internal off centered mass can be felt even though the walls of the balls and why spaghettification works like it does even through the walls of a ship.
Just a clarification of our chat yesterday and maybe we simply didn't understand each other.
Shell
New EMDrive Topic on NSF - Resonant Cavity Space Propulsion for Institutional Experiments and Theory
I've been meaning to alert our distinguished NSF emdrive readers & members that Dr Rodal has created a new emdrive thread specifically for Institutional Experimentation and Theory. This is a great way to expand the topic to a more specific audience. I expect this topic continue to expand like this in the future. Doc changes the name a bit, more descriptive for a fresh audience.
I encourage all those involved with Institutions to bookmark this NSF topic to read and participate:
http://forum.nasaspaceflight.com/index.php?topic=39214.20
Emdrive is growing here on NSF and this active main thread can be tedious to extract useful information, especially for Colleges and Universities who are considering experimental or theoretical participation. Of course, this is still welcomed on the main thread, but users might find it easier to discuss more specific details there. I believe Doc welcomes all, but I think its designed for shakers and movers at individual Institutions.
Good luck Doc on the related thread...don't go anywhere. Keep us posted on the stuff happening there
Well thank you
The purpose of the different thread is to have a thread where one can easily find proofs, more formal discussion and factual data, since the EM Drive threads have become so huge it is difficult for me to find things (I am guilty of posting too many comments on the EM Drive thread )
So, it is not meant as a competing thread but a small section for reference and discussion, just like we have the emdrive wiki for example
You will notice that the last contribution, concerning negative mass-energy, is under construction, but it is interesting to notice that
small deltaV/c acceleration (change in speed divided by the speed of light) requires very small amounts of negative mass-energy, if the (initial Velocity)/c is not extremely small
* by contrast,
deceleration using negative mass requires large amount of negative mass-energy, because it takes a negative mass equal to 100% of the magnitude of the initial total positive mass to start to decelerate
Tangential but I'm definitely going to use the Caillou reference to explain black holes to my boy, lol!
New EMDrive Topic on NSF - Resonant Cavity Space Propulsion for Institutional Experiments and Theory
I've been meaning to alert our distinguished NSF emdrive readers & members that Dr Rodal has created a new emdrive thread specifically for Institutional Experimentation and Theory. This is a great way to expand the topic to a more specific audience. I expect this topic continue to expand like this in the future. Doc changes the name a bit, more descriptive for a fresh audience.
I encourage all those involved with Institutions to bookmark this NSF topic to read and participate:
http://forum.nasaspaceflight.com/index.php?topic=39214.20
Emdrive is growing here on NSF and this active main thread can be tedious to extract useful information, especially for Colleges and Universities who are considering experimental or theoretical participation. Of course, this is still welcomed on the main thread, but users might find it easier to discuss more specific details there. I believe Doc welcomes all, but I think its designed for shakers and movers at individual Institutions.
Good luck Doc on the related thread...don't go anywhere. Keep us posted on the stuff happening there
Well thank you
The purpose of the different thread is to have a thread where one can easily find proofs, more formal discussion and factual data, since the EM Drive threads have become so huge it is difficult for me to find things (I am guilty of posting too many comments on the EM Drive thread )
So, it is not meant as a competing thread but a small section for reference and discussion, just like we have the emdrive wiki for example
You will notice that the last contribution, concerning negative mass-energy, is under construction, but it is interesting to notice that small deltaV/c acceleration (change in speed divided by the speed of light) requires very small amounts of negative mass-energy, if the (initial Velocity)/c is not extremely small
* by contrast, deceleration using negative mass requires large amount of negative mass-energy, because it takes a negative mass equal to 100% of the magnitude of the initial total positive mass to start to decelerate
It is amusing to find that
* it takes very little negative mass to accelerate if the resonant cavity has a finite speed but that
* it takes a negative mass exceeding the magnitude of the initial mass of the body to decelerate it
because this is reminiscent of TheTraveller quoting Shawyer that the EM Drive had to be "motivated" to accelerate, and Shawyer discussing the EM Drive in acceleration and deceleration as a motor or generator, respectively.
Except that what is required is initial speed/c >0 rather than vibration, etc.
Perhaps just a coincidence...
@ Rodal
Do you mean, that the EM drive needs a sort of kickstart? Like e.g. a mini rocket supplying the initial velocity for the first moments?
guys i have an article and a question or two...
Article:
http://www.sciencedaily.com/releases/2016/01/160128122011.htmthis is one of several "nature of time" themed articles and papers that popped up last week or this week.
Related to this specific article: so if time slips backwards per the article then doesn't ordinary energy or matter act as if it is exotic for whatever minute interval(?) the reversal of the arrow of time occurs? Could this momentary presence of negative energy and mass somehow be responsible for the weirdness in the EM drive?
