Quote from: Augmentor on 05/11/2018 03:32 pm[In it's simplest form, the derivative of force is defined byF' = A a^2 + B j vwhere v is velocity, a is acceleration, and j is jerk (change in acceleration) and A and B are constants.In the second term what is the velocity v relative to?

[In it's simplest form, the derivative of force is defined byF' = A a^2 + B j vwhere v is velocity, a is acceleration, and j is jerk (change in acceleration) and A and B are constants.

Quote from: Jim Davis on 05/12/2018 03:33 amQuote from: Augmentor on 05/11/2018 03:32 pm[In it's simplest form, the derivative of force is defined byF' = A a^2 + B j vwhere v is velocity, a is acceleration, and j is jerk (change in acceleration) and A and B are constants.In the second term what is the velocity v relative to?v is instantaneous, a measure of the external velocity. If v is the external instantaneous velocity of a body undergoing external acceleration then the jerk, j, is internal change.So we have another issue which appears to be a frame problem. What are v, a and j related to?Mach effects occur when a body undergoing external Newtonian acceleration also undergoes Relativistic internal change. Basically, in nested reference frames, Mach effects can occur. Localization from Machian universe where frame dragging results. Squeezed states result from compound acceleration and higher order derivatives, notably jerk. This brings up the question of whether a GR acceleration with Newtonian internal change results in Mach effects as well. The intuitive answer is yes. However, one needs to define GR acceleration...is it a curved path such that additional forces apply, say in a planetary or stellar gravitation field. First, a units check: j v == a^2 ?( m/sec^3) (m/sec) = m^2/sec^4 = (m/sec^2)^2Units wise, j v == a^2 On that basis, we can define the a^2 term as actually a(ext)* a(int) or identically a(int) * a(ext). Makes no difference, we can transpose them. So frames identical.F = A a^2 + B v j = A v'^2 + B v v'' = A (a(ext) * a(int)) + (v(ext) * j(int))If we assign jerk to internal changes and instantaneous v to external, then we have F = A a^2 + B j v = A (a(ext)* a(int)) + j(int) * v(ext) So in the j v term, we may need to use an alternative term, v(int) * j(ext). Will that work?F = A a^2 + B j v = A (a(ext)* a(int)) + v(int) * j(ext) Internal changes are not defined. However, we can assume the changes are either linear or angular. Linear jerk forces may be due to isolated energy changes, parametric amplification, or even parasitic forces including charge, mass and fields. Angular forces has additional forces which may result in acceleration change aka jerk forces. D

You've missed the point.

This is a nested system, a system within the system. Treat one system, treat the nested system, couple them together.

For a spaceship in space, v is relative to the rest of the universe. So stellar navigation is a requirement.For a soccer team moving a soccer balldown the field, one can pick v relative to either goal, or simply to the surface of the field.

The satellite example is really complex and nonlinear. Worse, changes to v, a and j mean that v', a' and j' add additional terms as well as g and g'. Since the path is curved, there are pseudo forces.

OTOH Mach effects are defined as a system undergoing acceleration with respect to the rest of the universe, and a relativistic change by E waves, produces internal change which creates a small transient gravitational/inertial change resulting in an overall change in Force.

So when a body accelerates it sends out a signal and as each element of the universe receives this signal it returns a gravitation/inertial signal which results in a change of force? How does the distance and direction of the various elements of the universe affect the magnitude and direction of the returned force? It seems to me that the various forces would largely cancel out since they are arriving from all directions over a very long period of time.

QuoteSo when a body accelerates it sends out a signal and as each element of the universe receives this signal it returns a gravitation/inertial signal which results in a change of force? How does the distance and direction of the various elements of the universe affect the magnitude and direction of the returned force? It seems to me that the various forces would largely cancel out since they are arriving from all directions over a very long period of time.My concern as well.Many pages ago, I posted a suspicion here that the this device might interact with the moons gravitational pull somehow - a local gravitational force strong enough to literally move oceans.

Quote from: ThinkerX on 05/16/2018 01:24 amQuoteSo when a body accelerates it sends out a signal and as each element of the universe receives this signal it returns a gravitation/inertial signal which results in a change of force? How does the distance and direction of the various elements of the universe affect the magnitude and direction of the returned force? It seems to me that the various forces would largely cancel out since they are arriving from all directions over a very long period of time.My concern as well.Many pages ago, I posted a suspicion here that the this device might interact with the moons gravitational pull somehow - a local gravitational force strong enough to literally move oceans.No, no, no! It instantaneously interacts with the fields of matter from the rest of the universe that "are already here". It's not a back-and-forth exchange of signals with distant matter. They refer to it as; Advanced Waves that propagate "backwards in time". However, I think that is misleading. Matter there has already radiated those waves and they are already here.

Quote from: flux_capacitor on 05/20/2018 01:28 pmIn the Wheeler-Feynman absorber theory, the "retarded" (orthochronous, or "forward in time") and "advanced" (antichronous, retrochronous or "backward in time") waves are actually the SAME wave, "recorded" from a different temporal perspective. The solution to the electromagnetic field equations in the Wheeler-Feynman absorber theory (which has been developed for electrodynamics) are symmetric with respect to time-inversion. But it has been suggested (first by Sciama) that such a concept could be extended to gravity. An object A (the emitter) suddenly accelerates (proper acceleration) at an instant t_{1}. It emits gravitational waves. These waves propagate forward in time through space at a velocity c (retarded solution). After some time, the wave arrives at a distant object B (the absorber) at an instant t_{2}.But the solution can bee seen oppositely, when reversing time (T-symmetry). Then it is the object B, the absorber, that emits a wave at t_{2}, which propages through space at a velocity c, for "some time" and finally arrives at the object A at the instant t_{1}, i.e. at the very same moment the object starts to accelerate in the orhochronous chronology. Therefore the advanced solution allows an instantaneous inertial (gravitational in essence) interaction between very distant objects through space and time, although the waves themselves propagate at a limited, finite velocity c.What is important to note, with respect to causality, is that the wave "coming back from the future" (more exactly the advanced solution) never propagates past in time before the moment of the object acceleration that initiated all of the waves.Things are little bit more complicated than that in the Wheeler-Feynman absorber theory. If you carefully read the original papers (Wheeler and Feynman 1945, 1949), you will find that there are six distinct waves in play:1. Retarded wave from the emitter2. Advanced wave from the emitter3. Retarded wave from the future absorber4. Advanced wave from the future absorber5. Retarded wave from the past absorber6. Advanced wave from the past absorberAll six waves should be taken into account + the boundary conditions of the universe in both time directions, as Hogarth did in his calculations (Hogarth 1962). You're talking about waves #1 and #4, and you are right that they are indistinguishable. But waves #2 do propagate backward in time before the moment of emission (from an anthropocentric view of time), and they violate our naive concept of causality:The hidden arrow of electromagnetic radiation: unmasking advanced waves http://philsci-archive.pitt.edu/13505

In the Wheeler-Feynman absorber theory, the "retarded" (orthochronous, or "forward in time") and "advanced" (antichronous, retrochronous or "backward in time") waves are actually the SAME wave, "recorded" from a different temporal perspective. The solution to the electromagnetic field equations in the Wheeler-Feynman absorber theory (which has been developed for electrodynamics) are symmetric with respect to time-inversion. But it has been suggested (first by Sciama) that such a concept could be extended to gravity. An object A (the emitter) suddenly accelerates (proper acceleration) at an instant t_{1}. It emits gravitational waves. These waves propagate forward in time through space at a velocity c (retarded solution). After some time, the wave arrives at a distant object B (the absorber) at an instant t_{2}.But the solution can bee seen oppositely, when reversing time (T-symmetry). Then it is the object B, the absorber, that emits a wave at t_{2}, which propages through space at a velocity c, for "some time" and finally arrives at the object A at the instant t_{1}, i.e. at the very same moment the object starts to accelerate in the orhochronous chronology. Therefore the advanced solution allows an instantaneous inertial (gravitational in essence) interaction between very distant objects through space and time, although the waves themselves propagate at a limited, finite velocity c.What is important to note, with respect to causality, is that the wave "coming back from the future" (more exactly the advanced solution) never propagates past in time before the moment of the object acceleration that initiated all of the waves.Things are little bit more complicated than that in the Wheeler-Feynman absorber theory. If you carefully read the original papers (Wheeler and Feynman 1945, 1949), you will find that there are six distinct waves in play:1. Retarded wave from the emitter2. Advanced wave from the emitter3. Retarded wave from the future absorber4. Advanced wave from the future absorber5. Retarded wave from the past absorber6. Advanced wave from the past absorberAll six waves should be taken into account + the boundary conditions of the universe in both time directions, as Hogarth did in his calculations (Hogarth 1962). You're talking about waves #1 and #4, and you are right that they are indistinguishable. But waves #2 do propagate backward in time before the moment of emission (from an anthropocentric view of time), and they violate our naive concept of causality:The hidden arrow of electromagnetic radiation: unmasking advanced waves http://philsci-archive.pitt.edu/13505

Having known Martin for years, we decided to LOAN him the device we had been using in our lab as a “demonstrator” for a couple of years. The device was shipped to him, along with some associated hardware – especially, a stepup/isolation transformer for the power circuit – so that he and his students could test it. He was to return the device and hardware in a month or two. It showed up in early June.…Running without the transformer had led them to run at the wrong frequency. But this aside, those in the popular and semi-popular press latched onto his ambiguous low power results and took them to be grounds for claiming that Mach effects had been falsified. Most of the press attention was lavished on the EM drive for there is no plausible physics to explain its operation should real thrust actually be generated in it. Mach effects were collateral damage.

Well this is some of the best news I have read in a while. MET is alive and kicking.

IMHO the tests were not valid and the experiment was not valid.

Take your pick...A) The future requires retesting of both drives. Try, try again. B) Fool me once, shame on you. Fool me twice, shame on me.C) Really, it was an interim report.D) At least the press spelled Tajmar correctly.

The new presentation shows strange data, usually with the "force" oscillating significantly while power is applied. Many artifacts in the data are not discussed in it

[..]until and unless Woodward retracts previous papers he has written that fail at high school level physics (discussed previously in this thread) data from him is not trustworthy (note: I am not claiming he is intentionally messing with data.)

Moreover, it seems to me that this is an unofficial Power Point presentation, not a published paper; there's a more in depth discussion on the noise sources and the way he accounted for them in his book.

Are you referring to his "Overunity" paper? I'm not aware of any other writing he made that contains glaring mistakes. It would surely benefit his credibility if he removed that article from SSI page.

By the way, if some mistake in basic physics was enough to destroy the credibility of a scientist one would expect to have seen this happen with all those scientist in the 1920s-40s that stated with no doubts that a rocket could not fly in a vacuum. Seemingly, this did not happen, and I don't even know if each one of them later corrected his previous remarks.

Not much to comment on, since we are more in agreement than not.Quote from: Povel on 06/28/2018 10:22 pmMoreover, it seems to me that this is an unofficial Power Point presentation, not a published paper; there's a more in depth discussion on the noise sources and the way he accounted for them in his book.I don't want to spend the time to go into the details now, but I recognize this presentation wasn't intended to answer everything.Quote from: Povel on 06/28/2018 10:22 pmAre you referring to his "Overunity" paper? I'm not aware of any other writing he made that contains glaring mistakes. It would surely benefit his credibility if he removed that article from SSI page.As far as I know it is just the one paper. Trust is easy to lose and can be hard to earn. Thankfully, we don't need to rely on trust since independent confirmation is a useful tool.Quote from: Povel on 06/28/2018 10:22 pmBy the way, if some mistake in basic physics was enough to destroy the credibility of a scientist one would expect to have seen this happen with all those scientist in the 1920s-40s that stated with no doubts that a rocket could not fly in a vacuum. Seemingly, this did not happen, and I don't even know if each one of them later corrected his previous remarks.As far as I am concerned that would have severely impaired their credibility with me. I have heard that claim before about scientists doubting rockets, but don't remember any firm sources. An attempt to google it just led to a bunch of flat earther sites (and a reminder that people today seriously promoting that level of ignorance is a real thing). I suspect it is primarily apocryphal, with a mix of misquotes and selective quotes similar to that whole bumblebee flying thing. If you have actual sources please share, though maybe in PM, since it isn't really on topic.