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The whole point of this essay is that Woodward is claiming that there is no problem with conservation of energy and so no reason to sneak in energy from some hypothetical Grav-Inertial Field. If there is a Grav-Inertial Field that the drive is reacting against then the entire essay is not only just as horribly wrong but entirely moot.And even if there were a Grav-Inertial Field you still have some hard questions about our relative velocity with it.
Quote from: ppnl on 12/25/2015 08:30 pmThe whole point of this essay is that Woodward is claiming that there is no problem with conservation of energy and so no reason to sneak in energy from some hypothetical Grav-Inertial Field. If there is a Grav-Inertial Field that the drive is reacting against then the entire essay is not only just as horribly wrong but entirely moot.And even if there were a Grav-Inertial Field you still have some hard questions about our relative velocity with it.I agree that is the point of the Essay. And I think everything up to but not including the last paragraph of the essay shows exactly that there is no CoE problem by simply doing a by first principles proof. The last paragraph honestly should never have been included in the Essay because after spending 5 pages showing how a CoE violation isnt allowed in newtonian physics. The next step should have been to show why a MET is a newtonian system. I get the impression he is assuming that the reader has read all or at least most of the recent work. Instead the last paragraph comes across to me as an off hand comment with very little context.
Quote from: birchoff on 12/25/2015 09:00 pmQuote from: ppnl on 12/25/2015 08:30 pmThe whole point of this essay is that Woodward is claiming that there is no problem with conservation of energy and so no reason to sneak in energy from some hypothetical Grav-Inertial Field. If there is a Grav-Inertial Field that the drive is reacting against then the entire essay is not only just as horribly wrong but entirely moot.And even if there were a Grav-Inertial Field you still have some hard questions about our relative velocity with it.I agree that is the point of the Essay. And I think everything up to but not including the last paragraph of the essay shows exactly that there is no CoE problem by simply doing a by first principles proof. The last paragraph honestly should never have been included in the Essay because after spending 5 pages showing how a CoE violation isnt allowed in newtonian physics. The next step should have been to show why a MET is a newtonian system. I get the impression he is assuming that the reader has read all or at least most of the recent work. Instead the last paragraph comes across to me as an off hand comment with very little context.The last paragraph is his entire conclusion without which all the rest is pointless. Look if Woodward wanted to say "Our drive is reacting against something else out there and so that potentially preserves both conservation of momentum and conservation of energy." Then I would say "Cool!, now lets talk about the properties of this something." We don't need to talk about other classical systems and figures of merit. But he didn't. He tried to say there was no violation of conservation of either energy or momentum without even mentioning that something. And constant acceleration with constant power. That will not fly.So maybe Woodward has other papers that talk about that something out there. If so then cool. But the paper cited does claim constant power with constant acceleration and the reasoning is horribly horribly wrong. Even if his drive works his reasoning is still wrong.
Sure we can agree to disagree but it isn't clear what we are agreeing to disagree on. That Woodward did say what he clearly said?No I have not read any papers by Woodward. I pretty much consider it junk science. If you have a paper in mind I may give it a glance but really if we can't agree on the merit of the simple essay at hand then I'm not sure more complex work is going to add anything.
Can we not revert to calling MET's reactionless
As for EmDrive's I personally dont care. Because there is no working theory of operation for it the only thing available to date are experimental results.
The only potentially viable theory by Dr. White from Eagle Works lab assumes that the Quantum Vacuum is not immutable and that the EmDrive is interacting with it. So from my personal perspective I think if it actually works It will probably end up being yet another propellant-less propulsion device.
the only thing that has been established in their theory papers is that it is possible for information about inertia/mass changes to be communicated over vast distances as long as the expansion of the universe is accelerating.
Now I wouldn't be surprised at all if Woodward/Fearn/Watsner have not completely characterized the properties of the Grav Inertial Field. [...]Finally. I have no problem with you or anyone else being a critic. Critique away I just reserve the right to challenge if I think your argument is flawed or lacking. And so far I would have to say your argument is lacking. because at least from my perspective to completely invalidate MET and Woodward Effect you would a complete definition of the properties of the Grav Inertial Field, or carry out a replication attempt and publish your results.
Quote from: ppnl on 12/25/2015 08:30 pmThe whole point of this essay is that Woodward is claiming that there is no problem with conservation of energy and so no reason to sneak in energy from some hypothetical Grav-Inertial Field. If there is a Grav-Inertial Field that the drive is reacting against then the entire essay is not only just as horribly wrong but entirely moot.And even if there were a Grav-Inertial Field you still have some hard questions about our relative velocity with it.I agree that is the point of the Essay. And I think everything up to but not including the last paragraph of the essay shows exactly that there is no CoE problem by simply doing a by first principles proof. The last paragraph [...]
I have already shown elsewhere that a rocket of any type cannot go over unity, whether or not it is mounted on a flywheel. I have also derived a condition that must apply to the Mach effect thruster if it works the way the equations seem to say it does (ie: no dependence of thrust on velocity) if global conservation of energy is to be respected.http://talk-polywell.org/bb/viewtopic.php?f=10&t=2215&p=103524#p103524http://talk-polywell.org/bb/viewtopic.php?f=10&t=2215&p=103729#p103729http://talk-polywell.org/bb/viewtopic.php?f=10&t=2215&p=105085#p105085Essentially, the effective mean velocity of the far-off active mass being interacted with must be invariant with respect to the thruster in order for energy to be conserved in all reference frames. The most plausible-seeming solution that presents itself is that the interaction happens in such a way (relativistic Doppler effect, perhaps? Something more esoteric? I need to catch up on the literature) that the effective mean velocity of the far-off active mass is always equal to that of the thruster.But we can dispense with the nonsense about critics doing the math wrong. Some do, but the upshot is that if the M-E thruster works as advertised, you can make something that looks exactly like a perpetual motion machine if you ignore the interaction with the rest of the universe.That interaction with the rest of the causally-connected universe is where the "extra" energy comes from. In fact it is the entire reason anything happens at all. The work done by an M-E thruster is largely unrelated to the local energy input, in the same sense in which the work done by the wind on a sailboat is largely unrelated to the energy expended by the crew moving the sails around. As far as I know there is no theoretical upper limit on the thrust efficiency of a Mach-effect device.
...No. Invoking a magic field doesn't change the nature of the device; for reasons I've tried to innumerate. (As have others.)...
...The experiments were only done because Shawyer/Cannae/etc had their various theories about why the effect should occur....
...If the quantum vacuum can be given a net velocity, that will completely change QM theory. If it can't, it can't work the way White believes (it becomes a free-energy machine, again.)...
...If the nature of the field is unknown, how can they "establish" anything? It has been claimed, it has not been established.But again, we can say from very basic physics that their claim, even if correct, does not solve the problem of the reactionless drive. The drive is already travelling too fast, relative to the cosmic background, for that background to be exerting a braking effect.As I said, and as I and others have tried to explain many times, if you claim the momentum is being exchanged with the deep-background you can't have both that exchange-mechanism preventing overunity and the claimed lab results. You can't have both. They are mutually exclusive....
...So they haven't "characterised" the field that I don't believe exists, but to be able to point out schoolboy errors in physics, I have to completely characterise the field that I don't believe exists...Bit of a double standard, don't you think?...
...{sigh} You missed that Woodward's entire argument is that the method used by critics to claim overunity for MET/etc can be equally applied to any conventional system. He does this by assuming that the conventional systems also have a constant acceleration/power ratio (his "figure of merit").He seems to completely fails to understand that it's the constant acceleration/power ratio which is fundamentally different about MET/etc. He didn't just trip in the last paragraph, his entire assumption is wrong....
...Given the form of Newton’s second law as stated in Equations (1) and (16), evencompetent physicists have come to believe that v dM/dt is a force, just as Ma is a force.But v dM/dt isn’t like an Ma force. This is usually illustrated in elementary physics textswith problems/examples like: a railway car moves along a smooth, level, straight,frictionless track with constant velocity. A pile of sand on the bed of the car is allowed tofall through a hole in the floor of the car. Does the speed of the car relative to the Earth(which can be taken to have effectively infinite mass) change as the sand falls? Acolleague who monitors the pedagogical literature tells me that people routinely mess thisup – and that at intervals of five to ten years, articles or blog comments addressing thisissue routinely appear. And, alas, that even those attuned to the subtleties of the issuemake mistakes in handling it.In the case of a rocket motor, the thing to observe is that there is one invariantvelocity involved: that of the exhaust plume with respect to the motor. All observers,irrespective of their own motions, agree on both the magnitude and direction of thisvelocity. And it is the velocity that yields momentum conservation....
Question for @Paul451 and @ppnlAre their any disagreements with what woodward says in this part of the EssayQuote...Given the form of Newton’s second law as stated in Equations (1) and (16), evencompetent physicists have come to believe that v dM/dt is a force, just as Ma is a force.But v dM/dt isn’t like an Ma force. This is usually illustrated in elementary physics textswith problems/examples like: a railway car moves along a smooth, level, straight,frictionless track with constant velocity. A pile of sand on the bed of the car is allowed tofall through a hole in the floor of the car. Does the speed of the car relative to the Earth(which can be taken to have effectively infinite mass) change as the sand falls? Acolleague who monitors the pedagogical literature tells me that people routinely mess thisup – and that at intervals of five to ten years, articles or blog comments addressing thisissue routinely appear. And, alas, that even those attuned to the subtleties of the issuemake mistakes in handling it.In the case of a rocket motor, the thing to observe is that there is one invariantvelocity involved: that of the exhaust plume with respect to the motor. All observers,irrespective of their own motions, agree on both the magnitude and direction of thisvelocity. And it is the velocity that yields momentum conservation....
You can't talk about a constant ratio of force to input power in a time invariant fashion for a closed system if you want to respect conservation of energy over time.
In an MET thruster, one also needs to carry one's F with them, in this case a source of electrical power, which will inevitably run out.Again, the Force can remain constant, within the limits of the machinery for a certain finite amount of time, but eventually, one runs out of F, that is, electricity.To my thinking, this means that one never gets to an 'over unity' situation, because one runs out of gas, as it were.