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#960 by JohnFornaro on 24 Sep, 2014 13:31
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Reviews of Modern Physics vol 36 pp463 and 1103
"The Physical Structure of General Relativity"
$35 gets you thru the paywall for this article:
http://journals.aps.org/rmp/abstract/10.1103/RevModPhys.36.463
The Erratum, you can have for free. Anybody care to share the article?
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#961 by JohnFornaro on 24 Sep, 2014 13:41
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Or a lot of negative results being kept secret while positive ones (or apparently positive ones) are published.
Yeah, there's that too. Remember way back when, when the Russians and us too, I suppose, were investigating mental telepathy as a "secret" weapon? Part of the due diligence of national security is to test seemingly weird things to verify whether or not there's "science" backing them up. Obviously, there would be great security issues as well as commercial issues surrounding a propellantless drive.
Point being, NDA's prove nothing about the underlying science one way or the other. Everybody is "free" to develop warp drive in their garage. The only rules that you have to follow apply to all matter in the universe.
Still, over the last several dozen pages, there are a raft of "special exceptions" being raised by posters. What about the cavity? The boundary conditions? The Comsol model? The dielectric? The sense I get is more along the lines of people grasping at straws, in the "hopes" that there is a "there" there, regarding this EM drive thingy.
There are all of these allusions to deep knowledge of the arcana surrounding the topic, but there is no coherent line of argument being made on this thread which starts at:Quote from: Sciama 1953If the rest of the universe determines the inertial frames, it follows that inertia is not an intrinsic property of matter, but arises as a result of the interaction of matter with the rest of the matter in the universe.
... and which concludes with propellantless propulsion.
Rodal has been patiently addressing each of the special execptions that posters have raised; exceptions which would seemingly allow a loophole explaining the reported thrust anomalies. In all of these cases, the posters appear to accept the apparently faulty inverted pendulum as being sufficiently accurate in its thrust reporting.
It's totally understandable from an emotional standpoint, why the experimentors hesitate to address the multiple skeptical arguments questioning their procedures and math, preferring to quietly assert that still, the device moves, though no other sees the movement.
Sheesh. <- Translate that! -
#962 by Rodal on 24 Sep, 2014 14:01
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Or a lot of negative results being kept secret while positive ones (or apparently positive ones) are published.
Yeah, there's that too. Remember way back when, when the Russians and us too, I suppose, were investigating mental telepathy as a "secret" weapon? Part of the due diligence of national security is to test seemingly weird things to verify whether or not there's "science" backing them up. Obviously, there would be great security issues as well as commercial issues surrounding a propellantless drive.
.........................Quote from: Sciama 1953If the rest of the universe determines the inertial frames, it follows that inertia is not an intrinsic property of matter, but arises as a result of the interaction of matter with the rest of the matter in the universe.
...............
It's totally understandable from an emotional standpoint, why the experimentors hesitate to address the multiple skeptical arguments questioning their procedures and math, preferring to quietly assert that still, the device moves, though no other sees the movement.
Sheesh. <- Translate that!
Totally agree with #1 (since China is examining Shawyer's microwave drive, it is understandable that NASA is requested to do the same here for microwave drives)
and with #2, excellent quote: according to Sciama "inertia is not an intrinsic property of matter", therefore Sciama's inertia cannot be a constitutive material property (it cannot be like the modulus of Elasticity in Stress-Strain equations or the Dielectric constant in Maxwell's expressions). Therefore if one uses Sciama's model, one cannot simultaneously add additional material-dependent "fudge factors" in order to explain why experimental results don't agree with theory. According to Sciama, inertia is not a material property, period, hence no additional material-dependent constants ("fudge factors") are allowed in his theory .
Dont't agree with your final note, John, [EDIT: ""X" has been patiently addressing each of the special execptions that posters have raised"] this is a joint [NASAspaceflight] community effort, of which I have been only a very small part and late to join. Thanks to all of you who have expressed your views (both agreeing and disagreeing with me): I have learnt a lot about these experiments from joining this forum. -
#963 by JohnFornaro on 24 Sep, 2014 14:26
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Dont't agree with your final note, John, this is a joint community effort, of which I have been only a very small part and late to join. Thanks to all of you who have expressed your views (both agreeing and disagreeing with me): I have learnt a lot about these experiments from joining this forum.
Not quite sure I understand this. Certainly, this is a community effort, and your patience and thouroughsity are appreciated by all and by me. but I was referring to the experimentors.
I do note that I have found a weakness in your translation skills! Sheesh. -
#964 by Notsosureofit on 24 Sep, 2014 14:30
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#2 The other side of the coin is that you can say the same thing about the Higgs field.
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#965 by Rodal on 24 Sep, 2014 14:45
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#2 The other side of the coin is that you can say the same thing about the Higgs field.
Good point, but the Higgs field is not introduced as a "fudge factor" multiplying expressions derived from General Relativity. If a theory (like Woodward's) that is derived from Sciama does not agree with experiments (because it gives changes in mass that are much lower than predicted or non-existent), it is not proper to try to fix it simply by introducing a "fudge factor".
EDIT: I am referring to the two "efficiency" fudge factors "eta1" and "eta2" with which Buldrini for example attempts to "fix" Woodward's theory on page 77 of this reference: http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=13020.0;attach=484587 . Buldrini himself admits this is a "rough" attempt to fix the theory. The "efficiency parameter" values are of an unknown nature and unknown magnitude, admitted by Buldrini as varying between 0 and 1. Obviously, if these fudge factors are zero, there is no Woodward effect. This is evidently a very unsatisfactory way to proceed in a derivation that pretends to originate from Sciama's Relativity Mach effect, as Sciama himself has stated that his Machian effect is not an intrinsic material property, and theories that are contradicted by experiment shouldn't be fixed with fudge factors.
Moreover, it is somewhat ironic to refer to Sciama's theory, whose intention was to remove inertia as an intrinsic property, and to end up with having to introduce (not one but) two additional intrinsic fudge factors of an unknown nature and unknown magnitude. -
#966 by Rodal on 24 Sep, 2014 14:47
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....
I do note that I have found a weakness in your translation skills! Sheesh.
EDIT: I was referring to your statement: <<"X" has been patiently addressing each of the special execptions that posters have raised>>.
Ciao e benvenuto
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#967 by 93143 on 24 Sep, 2014 21:25
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#2 The other side of the coin is that you can say the same thing about the Higgs field.
Good point, but the Higgs field is not introduced as a "fudge factor" multiplying expressions derived from General Relativity. If a theory (like Woodward's) that is derived from Sciama does not agree with experiments (because it gives changes in mass that are much lower than predicted or non-existent), it is not proper to try to fix it simply by introducing a "fudge factor".
EDIT: I am referring to the two "efficiency" fudge factors "eta1" and "eta2" with which Buldrini for example attempts to "fix" Woodward's theory on page 77 of this reference: http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=13020.0;attach=484587 . Buldrini himself admits this is a "rough" attempt to fix the theory. The "efficiency parameter" values are of an unknown nature and unknown magnitude, admitted by Buldrini as varying between 0 and 1. Obviously, if these fudge factors are zero, there is no Woodward effect. This is evidently a very unsatisfactory way to proceed in a derivation that pretends to originate from Sciama's Relativity Mach effect, as Sciama himself has stated that his Machian effect is not an intrinsic material property, and theories that are contradicted by experiment shouldn't be fixed with fudge factors.
Moreover, it is somewhat ironic to refer to Sciama's theory, whose intention was to remove inertia as an intrinsic property, and to end up with having to introduce (not one but) two additional intrinsic fudge factors of an unknown nature and unknown magnitude.
Did you even read the reasoning given for those "fudge factors"? In these drives, the "Mach effect" is supposedly being accessed indirectly by dynamic manipulation of materials via electromagnetic fields, the effectiveness of which necessarily depends on their properties (as well as on the precision of the resonance matching in the system, and the efficiency of the EM equipment in providing a clean signal). Your argument is a non sequitur. -
#968 by Rodal on 24 Sep, 2014 21:49
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Did you even read the reasoning given for those "fudge factors"? In these drives, the "Mach effect" is supposedly being accessed indirectly by dynamic manipulation of materials via electromagnetic fields, the effectiveness of which necessarily depends on their properties (as well as on the precision of the resonance matching in the system, and the efficiency of the EM equipment in providing a clean signal). Your argument is a non sequitur.
Not only I read it, but I provided the link to the actual paper (from an e-only, open access product focusing entirely on publishing conference proceedings ) where the author himself has the honesty and forthrightness to admit that as a first rough attempt to address the issues with Woodward's formulation, it seems reasonable to the author to insert into the mass fluctuation equation two efficiency parameter ranging between 0 and 1. For a value of zero, there is no Woodward effect. The author is right that it is rough to have to introduce such efficiency fudge factors. -
#969 by cuddihy on 24 Sep, 2014 22:05
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How is Buldrini's fudge factor different than the introduction of the Hubble constant?
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#970 by Rodal on 24 Sep, 2014 22:18
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How is Buldrini's fudge factor different than the introduction of the Hubble constant?
It differs in that
A) Hubble's law was first derived by Lemaître from General Relativity where he proposed the expansion of the universe and estimated the value of the rate of expansion. It was not a multiplicative fudge factor with possible values ranging from 0 to 1. (Lemaître also proposed what became known as the Big Bang theory of the origin of the Universe.)
B) Two years later Edwin Hubble determined a more accurate value for the Hubble constant based on actual measurements of the expansion of the Universe, again not a multiplicative fudge factor with possible values ranging from 0 to 1. -
#971 by JohnFornaro on 25 Sep, 2014 14:12
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"In these drives, the "Mach effect" is supposedly being accessed indirectly by dynamic manipulation of materials via electromagnetic fields, the effectiveness of which necessarily depends on their properties."
While it is true that it is the effectiveness of the properties of the materials used which determine the effectiveness of the forward momentum developed, it is also true that if the momentum generating device does not exist, then no material properties pertain to its effectiveness.
Example one: H2/O2 rocket engines are far more effective than compressed hummingbird wing/O2 rocket engines. Both of these rocket engines can be made and demonstrated, and their relative ISP's calculated with great accuracy.
Example two: No matter what I feed my pig, it will not fly until I pick it up and toss it. The pig does not have any flying properties. It may be possible to design and build a pig with sufficiently capable wings, but that theory of operation has not yet been developed.
Mach Effect drives will not work by tweaking an equation by an arbitrarily optimistic fudge factor. If the theory behind the operation is not soundly based on the way the universe actually works, no materials will suffice to make an M-E device work.
Example three: Coherent mathematical equation systems can be developed without regard to pragmatic utility of those systems in the universe as it exists.
In this "community effort", there is too much grasping of straws; straws which assume too much of unusual physical effects which are far removed from the starting point:Quote from: Sciama 1953If the rest of the universe determines the inertial frames, it follows that inertia is not an intrinsic property of matter, but arises as a result of the interaction of matter with the rest of the matter in the universe.
Unless Rodal accedes to my demand to start from this point and derive Woodward's Equation #3 for the community, I shall not buy him a Scotch this Friday after work. My decision is final. Plus, I double dog dare him. -
#972 by Rodal on 25 Sep, 2014 16:43
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The word "supposedly" used regarding Woodward's formulation. (First I heard it used in Woodward's response to a question from the audience on how can the effect be one of instantaneous action at a distance. (
[ ]
where I have on purpose timed it to when the question is asked, otherwise advance to the end of the presentation at 41:08 minutes (2468 sec)))
When it is stated that " "the Mach effect" is supposedly being accessed indirectly by dynamic manipulation of materials"
What is meant by "supposedly"?
is it:
A) a presumption that the justification is true absent conclusive evidence to the contrary
B) a presumption of what is assumed or believed by others
C) a warning that the person stating it is unsure and/or has reasons to doubt the justification
D) another meaning -
#973 by Rodal on 25 Sep, 2014 19:34
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In 2009 and 2010, Brito, Marini and Galian published a noteworthy experiment with negative results regarding Woodward's theory and a particular design of EM thrusters. Brito et. al.'s experiment had the ability to discriminate between thrusts in the uN (microNewton) range while the predicted Woodward thrust was 3.4 mN (milliNewton), orders of magnitude larger, yet the results showed no measurable thrust. These are the experimental reports:
2009, Hector H. Brito, Ricardo Marini and Eugenio S. Galian, "Null Findings on Electromagnetic Inertia Thruster Experiments using a Torsion Pendulum" 45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit 2 - 5 August 2009, Denver, Colorado
http://enu.kz/repository/2009/AIAA-2009-5070.pdf
2010, Ricardo L. Marini; Eugenio S. Galian , "Torsion Pendulum Investigation of Electromagnetic Inertia Manipulation Thrusting" Journal of Propulsion and Power, Vol. 26, No. 6 (2010), pp. 1283-1290
http://arc.aiaa.org/doi/abs/10.2514/1.46541?journalCode=jpp
Quoting from their report:
<<The thruster, is a self-contained unit including the propulsion modules and a battery operated 600W/1MHz power processing unit (PPU). Each module comprises a 30 turns toroidal coil wrapped around a ceramic housing containing a 10 nF - 8 mm wide annular capacitor with BaTiO3 ceramic dielectric (epsilonr ~ 4400). The capacitor-coil assembly is wired as a tank circuit and mounted in a common acrylic housing filled with a Phase Change Material (PCM), for limited thermal control of the assembly. The modules are wired in parallel to a common supply of 350 V- AC @ 1 MHz>>
<<For direct assessment of propulsive forces, a Cavendish-Coulomb method of detection based on a very sensitive single fiber torsion pendulum was implemented, together with a Kelvin laser measurement technique (see Fig. 4). ... The test unit being a self-contained one, spurious effects like inner motions, selfelectromagnetic couplings, piezoelectric, electro/magnetostriction, and thermal shifts of center of mass, are deemed to have a negligible influence on the setup dynamics. The thruster and its counterweight are fixed to a hollow cylindrical bar 0.4-m length, the whole fixture vertically suspended by a steel wire 0.8-mm dia., 2.45-m length. The suspension point was located 0.22 m from the thruster center of mass, and 0.15 m from the counterweight attachment point. The suspended fixture had a moment of inertia with respect to the wire axis of 0.937 kg-m2, and a free oscillation period of 168 s. A laser beam is reflected by a mirror fixed to the suspension wire onto a screen located 5.02 m from the suspension. The successive peak locations of the laser dot are marked on the screen following visual recording of the dot, thus performing a Kelvin laser measurement technique.>>
<<After conducting setup dynamics simulations involving varied initial conditions as well as activation times (t2 – t1), the setup was found to be able of discriminating thrusts in the N (microNewton) range, when the forces were applied according to the above mentioned procedure. However, under activation of the RAMA-II thruster in non-modulated power mode, no propulsive effect above that sensitivity range was observed, as shown in Table 1 where three successive peak locations are presented for each test, with the thruster activation occurring between peaks #2 and #3. In all tests two propulsive modules of four were activated to avoid PPU overheating and the measured supply voltage was 280 V, which yields an expected thrust around 320 mN, according to Eq. (1). Lower than nominal PPU output voltages were reported as related to poor current delivery capabilities of the employed lead-acid batteries, and built in current and temperature limitations to avoid propulsion modules and PPU overheating.>>
<<The observed negative results for [Brito's EM drive] activation in non-modulated power mode, imply that the following theoretical approaches are wholly or partially falsified: Transient mass fluctuation, Thrust predicted according to Woodward’s formulation is around 3.4 mN, thus according to the results reported here no Mach induced mass fluctuation is taking place up to the sensitivity of the experimental apparatus.>>
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#974 by Rodal on 25 Sep, 2014 19:37
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From Brito et.al.'s report, here is their table of results, and pictures of their setup
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#975 by Rodal on 25 Sep, 2014 19:43
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It is noteworthy that Brito et.al. used (for the experiments that showed no measurable thrust) the Cavendish hanging pendulum type that I have been advocating should be superior to the inverted pendulum apparatus used by NASA Eagleworks.
Observe, from the picture above, how simple is their setup for the Cavendish hanging pendulum damped by an oil bath compared to the NASA Eagleworks torsional inverted pendulum with magnetic dampening.
The Cavendish type of hanging pendulum is the setup that was used to perform the classical experiments to measure the inverse square law of gravitation as well as the Casimir force. Also observe that they used a simple oil bath as the damping device instead of the magnetic damping being used at NASA Eagleworks.
NASA Eagleworks reported that John Hopkins has a Cavendish type of pendulum that they were interested in using to verify the NASA Eagleworks experiments, I think that this should be much preferred rather than having to verify the NASA Eagleworks test with further tests using inverted torsional pendulums at JPL or NASA Glenn.
Also the test unit was a very compact self-contained setup with the whole unit together (including the power source), and they took care of a design to eliminate spurious effects like inner motions, selfelectromagnetic couplings, piezoelectric, electro/magnetostriction, and thermal shifts of center of mass. -
#976 by Rodal on 25 Sep, 2014 19:47
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It is also noteworthy that Brito et.al. found anomalous thrust measurements when their same EM drive was placed in an inverted pendulum:
<< a flex pendulum thrust stand using a high sensitivity piezoceramic strain transducer (PST). The experimental setup basically consists of mounting the thruster as a seismic mass atop a thin vertical cantilever beam, sitting on a vibration-free platform in a vibration isolated working place, as shown in Fig. 2. By using sine modulation of the supply (“carrier”) AC voltage, a modulated average thrust is theoretically achieved, at the modulation and twice the modulation frequencies, with amplitudes 1/2 and 1/8, respectively, of the non-modulated average thrust. By detecting this alternate force, the geomagnetic influence becomes averaged out; direct detection in frequency domain also permits to get rid of numerical artifacts>>
however <<the predicted mechanical effects are several orders of magnitude below those reported [with the inverted pendulum] here>>
They conclude with the statement <<Intensive testing is planned to assess the influence of potentially spurious effects, and to establish the dependence of the [inverted] flex pendulum amplitudes on the modulation frequency in order to identify the force producing mechanism as related to electrical quantities>>
The fact that their classical Cavendish type hanging pendulum found no measurable thrust (orders of magnitude below the predictions), while their inverted pendulum showed measurable thrust several orders of magnitude above the predictions shows the spurious nature of EM drive thrusts measured by the inverted pendulum. -
#977 by Rodal on 25 Sep, 2014 19:58
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Furthermore it is noteworthy that H.H.Brito had a career publishing reports claiming experimental measurements of propellant-less EM Drives prior to the above mentioned results:
1998 " A propulsion–mass tensor coupling in relativistic rocket motion"
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.54960
1999 "Propellantless Propulsion by Electromagnetic Inertia Manipulation: Theory and Experiment" http://www.intalek.com/Index/Projects/Research/0994.pdf
http://www.ovaltech.ca/pdfss/ElecMagInertia.pdf
2001/2004 "Experimental status of thrusting by electromagnetic inertia manipulation"
http://www.sciencedirect.com/science/article/pii/S009457650300225X
2003 " Direct Experimental Evidence of Electromagnetic Inertia Manipulation Thrusting"
http://arc.aiaa.org/doi/abs/10.2514/6.2003-4989
2005 "Overview of Theories and Experiments on Electromagnetic Inertia Manipulation Propulsion"
http://scitation.aip.org/content/aip/proceeding/aipcp/10.1063/1.1867270
2007 "Direct Experimental Evidence of Electromagnetic Inertia Manipulation Thrusting", Journal of Propulsion and Power, Vol. 23, No. 2 (2007), pp. 487-494
http://arc.aiaa.org/doi/abs/10.2514/1.18897?journalCode=jpp
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#978 by Rodal on 25 Sep, 2014 20:00
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As I wrote previously, the practical problem with independent verification (at John Hopkins -using their Cavendish type hanging pendulum- or other universities) is that the scientific community has dismissed the NASA propellant-less tests (either vocally as done by John Baez and Sean Carroll, or quietly as done by most other academics in Aerospace Engineering -and quietly dismissing these results at other NASA propulsion centers-). The academic community -particularly nowadays- knows that it is not considered to be an advancement to their career to produce independent experimental data that nullifies esoteric claims (claims that run contrary to conservation of momentum and known physics) that the rest of the community will meet with "I could have told you that". So academics at MIT, Stanford, CalTech, etc., are negatively motivated, they actually have a disincentive to spend their time and effort to examine these exotic claims.
Actually Woodward's effect has been lampooned in a 2006 news comic strip, see: http://angryflower.com/experi.html
And xkcd has lampooned the Quantum Vacuum explanation for the anomalous thrust measurements at NASA Eagleworks: http://www.explainxkcd.com/wiki/index.php/1404:_Quantum_Vacuum_Virtual_Plasma
So, it is very noteworthy that H.H.Brito and his colleagues published experimental results that nullified his previous experimental work, showing with a Cavendish-type balance no measurable thrust for the propellant-less EM drive. It is an outstanding demonstration of scientific honesty for Prof. Brito to have published these experimental results that nullify more than a decade of his previous efforts in propellant-less EM drives.
It is unusual to find people that had been measuring for more than a decade an esoteric effect to later produce experimental data that nullifies the very effect they were championing. -
#979 by Rodal on 26 Sep, 2014 01:53
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The subsequent 2010 AIAA Journal of Propulsion and Power paper by Milani and Galian
2010, Ricardo L. Marini; Eugenio S. Galian , "Torsion Pendulum Investigation of Electromagnetic Inertia Manipulation Thrusting" Journal of Propulsion and Power, Vol. 26, No. 6 (2010), pp. 1283-1290
http://arc.aiaa.org/doi/abs/10.2514/1.46541?journalCode=jpp
states this in even stronger terms:
<<The new results conclusively show that the devices tested do not produce the thrusts predicted by the theory, or those supposedly obtained before with the flexion [inverted] pendulum, not even up to 2 orders of magnitude lower. This strongly suggests that the positive results obtained with the flexion [inverted] pendulum would have been produced by spurious effects, very likely forces caused by electromagnetic interaction among some components of the electric circuit, which were not appropriately estimated.>>
