Quote from: mubahni on 05/09/2016 05:42 pmHallo wallofwolfstreet, can you comment on this paper?Thanks.Sure thing. Unfortunately the pdf has content copying not allowed, so I can’t just copy and paste. To save myself time I’ll just offer the first little bit of a section I want to quote and you can ctrl+f it. Apologies in advance for any mistakes in copying. In general, the paper offers a result that is completely consistent with the Oak Ridge Scientists (ORS) interpretation of the correct form of the equation of motion for a variable mass system (John Cramer of the University of Washington also advances this equation of motion, see the second paragraph of the intro of this 2004 paper).Right in the abstract, Wanser writes:QuoteThere is no rocket type thrust in the usual sense of ejecting propellant, since it is supposed that there is no relative velocity along the direction of motion associated with the mass changes.Emphasis mine.This assumption of zero relative velocity is critical, because it allows him to present F=ma+dmdtvrel as just F=ma (i.e. he has reduced the general equation of motion to the Woodward's equation of motion under the constraint that vrel=0). To be honest, I kind of feel that this paper is presenting a bit of a trivial result. It is simply showing that when the mass flow into and out of a variable mass system is contrived so that there is no net relative velocity, then the center of mass of the open system can be made to accelerate. This is basically what Mezzenile has said in his preceding posts. The issue is, in order for the mass that flows in and out of the system to have vrel=0 despite the acceleration of the MET, there must be some net force accelerating this variable mass, which Wanser correctly identifies in his Discussion:(start reading at ‘the center of mass of the cart’)Quote…This momentum must be made up by the rest of the universe allowing the isotropically ejected mass (in the rest frame of the accelerating body) to return isotropically to the body in its rest frame, that has in the mean time accelerated forward, to keep pace with the MET device, thus requiring the “spherical shell of ejected mass to move forward.Wanser also reiterates that the results are contingent on assuming vrel=0. It’s this assumption that doesn’t have any theoretical motivation as being applicable to METs as far as I can see, and in fact Woodward routinely advances explanations as to how you can set vrel=0 which just aren’t consistent with physics.QuoteThe unidirectional acceleration found here is a consequence of our primary assumption, the possibility of changing the mass of an isolated system with zero relative velocity associated with the net convective momentum flux which produces the changing mass Essentially, what Wanser has done is what I consider to be a bit of slight of hand (at least in regard to METs). He has moved the problem from within a control volume containing the MET to outside the control volume. The only way the variable mass can consistently have vrel=0 despite the claimed acceleration of the MET is that somehow the variable mass which exists outside the control volume is being accelerated by some unknown force alongside the MET. The question is simply reframed from “what causes the MET to accelerate?” to “what causes the variable mass outside the system boundary of the MET to accelerate with the MET, so the net velocity of this mass is always just right to ignore vrel dependent terms?”So like I said, I think this result is a bit trivial, because it just flips the problem definition around, demonstrating that it is possible to self-accelerate a variable mass system if you are somehow able to accelerate the variable mass when it is outside your control volume boundary. I don’t think that's a very surprising result. There are a few things in the paper that I disagree with (Newton’s third law more fundamental that Conservation of Momentum? – I don’t think so), but I don’t think they are particularity relevant to the question at hand.
Hallo wallofwolfstreet, can you comment on this paper?Thanks.
There is no rocket type thrust in the usual sense of ejecting propellant, since it is supposed that there is no relative velocity along the direction of motion associated with the mass changes.
…This momentum must be made up by the rest of the universe allowing the isotropically ejected mass (in the rest frame of the accelerating body) to return isotropically to the body in its rest frame, that has in the mean time accelerated forward, to keep pace with the MET device, thus requiring the “spherical shell of ejected mass to move forward.
The unidirectional acceleration found here is a consequence of our primary assumption, the possibility of changing the mass of an isolated system with zero relative velocity associated with the net convective momentum flux which produces the changing mass
So in short. your calling into question the explaination used to argue that the mass change said to affect the FM component of a MET device can be done in a manner that is consistent with known physics?
Unfortunately, this scheme for observing theinertia variation appears to be at odds with therelativistically invariant form of Newton's 2nd law ofmotion:F = dp/dt = mdv/dt + vdm/dt (1)Since the inertial mass m of the test body isexpected to vary with time, the last term of Equation(1) cannot be ignored. It is not surprising, in view ofNewton's 3rd law of motion, that for any sinusoidalvariations of the mass around a central value, the forcecontribution from the v dm/dt term is found toprecisely cancel the supposed "unbalanced force"arising from the m dv/dt term, leading to a time averagednet force of zero on the overall system.From this simple calculation, it appears thatunbalanced force searches are not good tests of theproposed effect. There remains the question ofwhether the Woodward inertia variation is present in asystem having an energy flow. In the present work, wehave devised two tests of this effect that do not require thepresence of an unbalanced inertial force.
Quote from: birchoff on 05/09/2016 10:47 pmSo in short. your calling into question the explaination used to argue that the mass change said to affect the FM component of a MET device can be done in a manner that is consistent with known physics?In short, Yes.This is basically my read on Mach effects and Woodward's work:There are three Mach effects proposed by Woodward. The first Mach effect (also called the Woodward effect) is proposed to cause transient mass fluctuations. It is then proposed that by fluctuating a mass (the FM component of an MET) in phase with a cyclical displacement one can generate acceleration of a closed system. It is this second proposal that lacks a coherent derivation in my opinion. I honestly don't have the theoretical grounding in general relativity or the work of Sciama to either confirm or deny whether the first proposal has a valid derivation.Transient mass fluctuations may or may not be real, but transient mass fluctuations do not necessarily imply METs. I'm not the first person to take this view either. It is essentially the view taken by Cramer et al. (2004) in Test of Mach's Principle with a Mechanical OscillatorQuoteUnfortunately, this scheme for observing theinertia variation appears to be at odds with therelativistically invariant form of Newton's 2nd law ofmotion:F = dp/dt = mdv/dt + vdm/dt (1)Since the inertial mass m of the test body isexpected to vary with time, the last term of Equation(1) cannot be ignored. It is not surprising, in view ofNewton's 3rd law of motion, that for any sinusoidalvariations of the mass around a central value, the forcecontribution from the v dm/dt term is found toprecisely cancel the supposed "unbalanced force"arising from the m dv/dt term, leading to a time averagednet force of zero on the overall system.From this simple calculation, it appears thatunbalanced force searches are not good tests of theproposed effect. There remains the question ofwhether the Woodward inertia variation is present in asystem having an energy flow. In the present work, wehave devised two tests of this effect that do not require thepresence of an unbalanced inertial force.
...In short, Yes.This is basically my read on Mach effects and Woodward's work:There are three Mach effects proposed by Woodward. The first Mach effect (also called the Woodward effect) is proposed to cause transient mass fluctuations. It is then proposed that by fluctuating a mass (the FM component of an MET) in phase with a cyclical displacement one can generate acceleration of a closed system. It is this second proposal that lacks a coherent derivation in my opinion. I honestly don't have the theoretical grounding in general relativity or the work of Sciama to either confirm or deny whether the first proposal has a valid derivation.Transient mass fluctuations may or may not be real, but transient mass fluctuations do not necessarily imply METs. I'm not the first person to take this view either. It is essentially the view taken by Cramer et al. (2004) in Test of Mach's Principle with a Mechanical OscillatorQuoteUnfortunately, this scheme for observing theinertia variation appears to be at odds with therelativistically invariant form of Newton's 2nd law ofmotion:F = dp/dt = mdv/dt + vdm/dt (1)Since the inertial mass m of the test body isexpected to vary with time, the last term of Equation(1) cannot be ignored. It is not surprising, in view ofNewton's 3rd law of motion, that for any sinusoidalvariations of the mass around a central value, the forcecontribution from the v dm/dt term is found toprecisely cancel the supposed "unbalanced force"arising from the m dv/dt term, leading to a time averagednet force of zero on the overall system.From this simple calculation, it appears thatunbalanced force searches are not good tests of theproposed effect. There remains the question ofwhether the Woodward inertia variation is present in asystem having an energy flow. In the present work, wehave devised two tests of this effect that do not require thepresence of an unbalanced inertial force.
Thank you for clarifying that. In that case your critique of the paper Flux Capacitor posted a few posts back, in light of your your comments on the Wasner paper that mubahni posted to the forum; Is either misdirected, wrong, or I am simply reading more into it than you intended.
Since that paper explains pretty much the same thing that the wasner paper does, with one difference that I think is a minor one.
One way to demonstrate why Woodward’s equation of motion is wrong is to consider a flatcar rolling down a smooth level track at constant velocity, where a hopper from above is pouring sand onto the cart. This is the exact inverse of Woodward’s thought experiment, so Woodward’s equation of motion, F=m(t)dv/dt, should be applicable …My question is this: Does the flatcar in my example accelerate, or continue to travel at constant velocity when the sand is being poured onto the flatcar?So people who read Woodward’s rebuttal and actually thought it made sense, please use Woodward’s equation of motion in this instance to make a prediction: does the flatcar slow down or not? What does the Woodward equation of motion predict, what does the ORS equation of motion predict, and what actually happens?
It does not explicitly state that it is making the assumption that it is possible to create a system where one can change the mass of a component in just such a way that it is possible to zero out the vdm/dt term. The paper in question basically assumes such a thing is possible and talks about an example of such a system.
The Wasner paper goes a bit further on the analysis of why such a thing doesnt violate newtons second law, and takes as an assumption that the Mach Effect demonstrated in the MET device is capable of changing the mass in the FM component as described.
So I would definately ask. What is missing from the work Woodward and Fern has done so far?
N.B. Where did you see there were three Mach Effects. Woodward has only ever talked about two Mach Effects. First one is the transient mass change (impulse) term, and the second one is referred to as the Worm Hole term.
The Woodward effect, also referred to as a Mach effect, one of at least three predicted Mach effects…According to Woodward, at least three Mach effects are theoretically possible: vectored impulse thrust, open curvature of spacetime, and closed curvature of spacetime
So now that i have a little sleep in me. Something else has occured to me about your critique. Why assert that cramer takes the perspective that you quoted. When in the Wasner paper, that you seem to agree with, it is said that Cramer incorrectly includes the vdm/dt term because it the transient mass change as far as the wasner paper is concerned is the type of mass change that allows you to set that term to 0. What I would expect to see in the Cramer paper is some exposition on why the transient mass change term in woodwards derivation would not lead to the type of mass change that allows you to set the vdm/dt term to 0.
I think what gets on my nerves most about this criticism is that both sides seem to be talking past each other. Woodward pretty much believes that the theoretical work he has done up till now justifies that the transient mass change is such that you are allowed to set the vdm/dt term to 0. While criticisms I have seen so far amount to saying "YOU CAN NEVER SET THE vdm/dt TERM to ZERO".
Even though the Wasner paper outlines a thorough explaination of when you are allowed to set the vdm/dt term to zero.
So either the Wasner paper is pure rubbish, or it isnt and there are specific situations where you are allowed to do what woodward has done.
We can not have any net ejection of mass in a cyclic process, so this condition is satisfied if, we assume that mass fluctuations are of this type, i.e. that vrel=0
Personally I think the ball is in the critics court mostly because Woodward has laid out his step by step derivations in published work and provided alot of exposition explaining his reasoning.
Anyway. now that I understand what your criticism is. I think the focus on newtons equation of motion is misplaced. The real focus as I see it should be on why Woodward's transient mass change term does not produce an effect that allows the vdm/dt term of the equation of motion to be set to 0.
I discover the here above cited article from Cramer et al. (2004) : Test of Mach's Principle with a Mechanical OscillatorIt is a pity to see that even seasoned professionals occasionally make mistakes when applying the second law, even in simple circumstances :The first equation of the article (F = dp/dt = mdv/dt + vdm/dt) is introduced as beeing the relativistically invariant form of Newton's 2nd law of motion.But this formulation is FALSE. The term vdm/dt is completely wrong ! It should be replaced by udm/dt where u is a speed that all observers can agree on and so which has an invariant meaning – for example, the velocity of the just ejected exhaust plume of a rocket with respect to the rocket ( and not the speed v of the rocket !).Apparently the three distinguished authors of the article : John G. Cramer , Curran W. Fey, and Damon V. Casissi are not yet fully convinced that rockets can work !!!
True, it would have been better for them to have been more rigorous and use the correct expression with relative velocity. Goes to show how easy it is to get tripped up. This trip up reduces the generality of Equation (7), but it doesn't adversely affect the paper as a whole.
Quote from: wallofwolfstreet on 05/22/2016 04:17 amTrue, it would have been better for them to have been more rigorous and use the correct expression with relative velocity. Goes to show how easy it is to get tripped up. This trip up reduces the generality of Equation (7), but it doesn't adversely affect the paper as a whole. It is not only a question to be more rigorous and to use the correct expression. It challenges also the main thesis of the article which relies on this false equation together with what the authors call a “simple calculation” to support the claim that the searches of unbalanced force are not good tests of the Woodward effect. This beeing said does somebody know if the authors finally managed to get rid of the the spurious excitation which perturbated their measurements ?
I see your point. but after my discussion with wallofwolfstreet. I am beginning to understand that the core problem here isnt so much what that term in the equation of motion means. Its whether or not the effect being displayed is allowed to zero out that term in the equation of motion.
So the million dollar question remains, where in the work woodward et al have done does it show that the transient mass fluctuation mach effect is just such an effect that allows you to zero out that term in the motion equation.
This beeing said does somebody know if the authors finally managed to get rid of the the spurious excitation which perturbated their measurements ?
Quote from: Mezzenile on 05/22/2016 12:47 pmQuote from: wallofwolfstreet on 05/22/2016 04:17 amTrue, it would have been better for them to have been more rigorous and use the correct expression with relative velocity. Goes to show how easy it is to get tripped up. This trip up reduces the generality of Equation (7), but it doesn't adversely affect the paper as a whole. It is not only a question to be more rigorous and to use the correct expression. It challenges also the main thesis of the article which relies on this false equation together with what the authors call a “simple calculation” to support the claim that the searches of unbalanced force are not good tests of the Woodward effect. This beeing said does somebody know if the authors finally managed to get rid of the the spurious excitation which perturbated their measurements ?I see your point. but after my discussion with wallofwolfstreet. I am beginning to understand that the core problem here isnt so much what that term in the equation of motion means. Its whether or not the effect being displayed is allowed to zero out that term in the equation of motion.So the million dollar question remains, where in the work woodward et al have done does it show that the transient mass fluctuation mach effect is just such an effect that allows you to zero out that term in the motion equation.Personally I think the answer to that question is the experimental evidence that woodward is building. Their theory argues that this particular mach effect should work this way. Now they are on to proving that their experiments match their theoretical predictions.
In this video, Nembo Buldrini seems to talk and even present results of a replication...
Dr. Rodal,In light of the presentation you recently did on HN Theory. I would love to know what your take is on where Woodward and Fearn are as far as having a theory that can be used to describe Mach Effects. To the best of my knowledge the last step needed for then to be able to confidently claim their theory is accurate is being able to derive force equations from it that accurately predict thrust. Which means they need to build better MET devices to test thrust scaling as predicted. Are there other things Heidi and Woodward need to do that we are not aware of?
Quote from: birchoff on 09/25/2016 01:40 pmDr. Rodal,In light of the presentation you recently did on HN Theory. I would love to know what your take is on where Woodward and Fearn are as far as having a theory that can be used to describe Mach Effects. To the best of my knowledge the last step needed for then to be able to confidently claim their theory is accurate is being able to derive force equations from it that accurately predict thrust. Which means they need to build better MET devices to test thrust scaling as predicted. Are there other things Heidi and Woodward need to do that we are not aware of?1. I presented an exact solution for the force (under suitable, well specified assumptions) and its comparison with experiments. Prior to the workshop, Prof. Hearn actually independently checked the validity of my solution (which comprises hundreds of terms) by hand !2. The solution predicts the optimal mass for the tail mass section, in agreement with experiments. The solution correctly predicts the direction of the force. The solution predicts the extreme dependence of the amplitude of the force with other parameters in the vicinity of resonance. The solution also predicts other effects.3. The solution shows various ways on how it may be possible to increase the force from what has been demonstrated in experiments up to now.4. In addition, at the Estes Park Breakthrough Propulsion workshop, a physicist that works with General Relativity presented another derivation of Woodward's equation based on linearization of Einstein's General Relativity. 5. In addition, at the Estes Park Breakthrough Propulsion workshop independent experimental measurements of the Mach/Sciama/Wooward effect force were presented from 3 other researchers, in 2 separate continents.----- You will be able to watch my presentation (as well as other presentations) at the Space Studies Institute website: www.ssi.org and ensuing discussion with the participants.
Quote from: Rodal on 09/25/2016 01:59 pmQuote from: birchoff on 09/25/2016 01:40 pmDr. Rodal,In light of the presentation you recently did on HN Theory. I would love to know what your take is on where Woodward and Fearn are as far as having a theory that can be used to describe Mach Effects. To the best of my knowledge the last step needed for then to be able to confidently claim their theory is accurate is being able to derive force equations from it that accurately predict thrust. Which means they need to build better MET devices to test thrust scaling as predicted. Are there other things Heidi and Woodward need to do that we are not aware of?1. I presented an exact solution for the force (under suitable, well specified assumptions) and its comparison with experiments. Prior to the workshop, Prof. Hearn actually independently checked the validity of my solution (which comprises hundreds of terms) by hand !2. The solution predicts the optimal mass for the tail mass section, in agreement with experiments. The solution correctly predicts the direction of the force. The solution predicts the extreme dependence of the amplitude of the force with other parameters in the vicinity of resonance. The solution also predicts other effects.3. The solution shows various ways on how it may be possible to increase the force from what has been demonstrated in experiments up to now.4. In addition, at the Estes Park Breakthrough Propulsion workshop, a physicist that works with General Relativity presented another derivation of Woodward's equation based on linearization of Einstein's General Relativity. 5. In addition, at the Estes Park Breakthrough Propulsion workshop independent experimental measurements of the Mach/Sciama/Wooward effect force were presented from 3 other researchers, in 2 separate continents.----- You will be able to watch my presentation (as well as other presentations) at the Space Studies Institute website: www.ssi.org and ensuing discussion with the participants.So I am going to beg your forgiveness for what I am about to do...INNER SPACE GEEK > IT WORKS!!!!!!?Translation > Given the strong theoretical support. Are you saying that the only thing left is engineering?Also, I am curious to know if you spent anytime reflecting on the possibility for Mach Effects to "POTENTIALLY" allow the creation of worn holes. I know unlike the thrust term. The Worm hole creation part still has theoretical rough spots. In particular the use of the ADM model of the electron. However, if you have I was curious about your take on that part of Woodward's derivation of Mach Effects.