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Old 08-04-2014, 04:31 PM   #76
kamaz
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Please excuse me for being nosy, but have you actually read the Brady et.al. paper?

Because I am looking at it right now, and inventor's claims as to what should work have no bearing on the results.

---------- Post added at 05:31 PM ---------- Previous post was at 05:25 PM ----------

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Originally Posted by boogabooga View Post
 That's my point. The simulation will only include "conventional" physics. If "unconventional" physics appear in the simulation, it's because the simulation was already programmed to include it.

You can't use a simulation of conventional physics as a validation of unconventional physics.
The paper says that the numerical simulation was used to determine the electromagnetic field distribution inside the test article. No new physics here.
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Old 08-04-2014, 04:34 PM   #77
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Originally Posted by kamaz View Post
 The inventor claimed that his experimental setup produces a unbalanced force.

NASA replicated his setup and found that the setup indeed produces a force.
FTFY

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 It is not known at this point if the force was indeed produced by the device itself, or by some unaccounted for coupling in the experimental setup.
That is exactly true. But now is the pesky matter of the burden of proof. Simply producing a force on a test rig is not sufficient. For the fourth time, until it can be shown that there was not a coupling with the setup, environment, etc. and thus a violation of conservation of momentum, this simply does not deserve the hype that it is getting.


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 This is why it should be investigated further.
Sure, investigate away. If you have the time and the money, why not.

BTW, just because a few frauds have slipped through peer review, does not mean that research that has not been per reviewed should be assumed to be as good as research that has.

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 The paper says that the numerical simulation was used to determine the electromagnetic field distribution inside the test article. No new physics here.
I was referring to claims made not in the paper but on his website, which has since been mysteriously taken down.

Last edited by boogabooga; 08-04-2014 at 04:37 PM.
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Old 08-04-2014, 04:50 PM   #78
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Originally Posted by boogabooga View Post
 and thus a violation of conservation of momentum
Per this paper on White's theory there is no violation of conservation of momentum any more then there is in case of a paddle boat.

Fetta's theory of device operation would require violating conservation of momentum, but the experiment has showed that it is incorrect. (Surprise!)
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Old 08-04-2014, 04:54 PM   #79
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Originally Posted by kamaz View Post
 Please excuse me for being nosy, but have you actually read the Brady et.al. paper?
I have only the abstract available.

But I had understood it wrong: I thought that they tested three devices, but in reality they only tested a Cannae and the Null article and BOTH produced thrust.

The cannae thruster 30-50 N, the null article designed to produce no force at all produced 90 N!

Case closed for me. The experiment design was wrong, and a new experiment has to be devised.

The jumping to conclusion "Quantum Vacuum Plasma potentially exists" is bad science: Better would be the formulation: "Quantum Vacuum Plasma hypothesis was invalidated by the experiment results"
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Old 08-04-2014, 05:31 PM   #80
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 But I had understood it wrong: I thought that they tested three devices, but in reality they only tested a Cannae and the Null article and BOTH produced thrust.
Incorrect. There were 3 test articles. 2 test articles were provided by Cannae. The articles were the same, except that one of the had holes on one side the RF cavity. The third article was a 50 ohm resistor. Only the third article produced no thrust.

The test article is a short, wide cylinder. During the test, the device is mounted horizontally ('cause gravity). Fetta (Cannae) theorized that the device works by having particles bouncing off between the "left" and "right" walls of the cylinder back and forth. However, in such case the net force is zero, because the force exerted on the left plate is the same as the force exerted on the right plate. (This is test article #2, a.k.a. "unslotted"). So he had another article, which had holes drilled in the "right" plate, permitting particles to escape. If the holes were, say, 20% of the plate surface, then the force on one plate would be reduced by 20% -- as 20% of particiles would escape through the holes -- and this would produce thrust. (This is test article #1, a.k.a. "slotted").

Test article #1 produced 40.0uN of thrust on average, test article #2 produced 40.7uN of thrust on average. Since there's some spread in the data from run to run, it looks like both articles produced the same thrust.

Test article #3 (a.k.a. resistor) produced no thrust. (This is not entirely true -- the authors say that they have measured 9uN of force in the configuration involving the resistor due to magnetic field from the feed cable pushing the torsion pendulum, so they have substracted 9uN from all results.)

Most of the confusion stems from the fact that the abstract refers to the "unslotted" article as null. This is because it was a null for Fetta's theory that the thrust is produced by holes in the wall of the RF cavity.
Attached Thumbnails
setup.jpg   cannae_test_article.jpg   results.png  

Last edited by kamaz; 08-04-2014 at 05:38 PM.
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Old 08-04-2014, 05:52 PM   #81
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Sorry, but that is wrong:

Quote:
Originally Posted by Brady et al.
 Thrust was observed on both test articles, even though one of the test articles was designed with the expectation that it would not produce thrust. Specifically, one test article contained internal physical modifications that were designed to produce thrust, while the other did not (with the latter being referred to as the "null" test article).
There was no "test article #3" in the Brady paper.

What you mean is that one:

Quote:
Originally Posted by Brady et al.
 In addition, the test article was replaced by an RF load to verify that the force was not being generated by effects not associated with the test article.
That was done by calibration, but again says little about the experiment having no conventional physics cause. The RF load just stood in place of the experiment, but then, the parameters of this RF load and which assumptions had been behind scaling this RF Load is not known to me. But would be interesting.

Last edited by Urwumpe; 08-04-2014 at 05:57 PM.
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Old 08-04-2014, 06:00 PM   #82
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Originally Posted by Urwumpe View Post
 There was no "test article #3" in the Brady paper.
Test article #3 refers to the load resistor -- it was mounted in place of the test articles to investigate possible RF coupling effects -- and it predictably generated no thrust.

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 That was done by calibration, but again says little about the experiment having no conventional physics cause.
1. What is your proposed mechanism for the Cannae test articles producing thrust in vaccuum?

2. What is your proposed mechanism for tapered cavity test articles (section IV) producing thrust in vaccuum?

Last edited by kamaz; 08-04-2014 at 06:03 PM.
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Old 08-04-2014, 06:40 PM   #83
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 1. What is your proposed mechanism for the Cannae test articles producing thrust in vaccuum?

2. What is your proposed mechanism for tapered cavity test articles (section IV) producing thrust in vaccuum?
The test was not done under vacuum conditions, but ambient air conditions.

Quote:
Originally Posted by Brady et al.
 Testing was performed on a low-thrust torsion pendulum that is capable of detecting force at a single-digit micronewton level, within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure.
Their experiment procedure involved moving the test articles in and out of the test chamber for tuning, so they had decided against using vacuum.

And as explanation: The test was done in a stainless steel chamber and reached its peak performance at a specific frequency, using a metallic waveguide as "thruster". Thus, I would not even exclude simple induction as source of the force. The 4 N thrust per kW RF power is also on the magnitude at which I would first-guess-timate such electromagnetic interaction between test article and test chamber.

The RF load has a different geometry and does not induce magnetic fields like the two test articles, which would then also explain the difference. That the non-slotted variant is more "powerful" than the slotted version is also explainable by that hypothesis.

But I would need much more information about the experiment to have a more solid hypothesis than this. But magnetic interactions between antennas are no new phenomena, so why should I not start there first?

Last edited by Urwumpe; 08-04-2014 at 06:45 PM.
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Old 08-04-2014, 06:46 PM   #84
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Possible. That would explain the thrust difference after rotating the test article.

The most interesting fact though is that the paper mentions that White's group has been investigating RF cavity thrusters since 2013.
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Old 08-04-2014, 06:49 PM   #85
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Originally Posted by kamaz View Post
 Possible. That would explain the thrust difference after rotating the test article.

The most interesting fact though is that the paper mentions that White's group has been investigating RF cavity thrusters since 2013.
Not really that interesting... A quick check on what Brady did in the past revealed research in optical neural networks. All seem to be in the more "experimental" field... could be part of a strategy to risk many boring experiments in different technologies for the single spectacular one. Or that they are just kept busy with such research to get a better "publication quota" in their institutes.
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Old 08-04-2014, 06:54 PM   #86
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Originally Posted by Urwumpe View Post
 The test was not done under vacuum conditions, but ambient air conditions.

Their experiment procedure involved moving the test articles in and out of the test chamber for tuning, so they had decided against using vacuum.
Where does it say that?

---------- Post added at 07:54 PM ---------- Previous post was at 07:51 PM ----------

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 Not really that interesting... A quick check on what Brady did in the past revealed research in optical neural networks.
So? If you looked through my publication history you'd find papers across 4 major fields.
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Old 08-04-2014, 07:01 PM   #87
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Originally Posted by kamaz View Post
 Where does it say that?
The abstract, I had also included it above:

Testing was performed on a low-thrust torsion pendulum that is capable of detecting force at a single-digit micronewton level, within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure...Integration of the two test articles and their supporting equipment was performed in an iterative fashion between the test bench and the vacuum chamber. In other words, the test article was tested on the bench, then moved to the chamber, then moved back as needed to resolve issues. Manual frequency control was required throughout the test.

Tells a story.

---------- Post added at 09:01 PM ---------- Previous post was at 08:55 PM ----------

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 So? If you looked through my publication history you'd find papers across 4 major fields.
Still much more than mine.
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Old 08-04-2014, 07:23 PM   #88
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 So? If you looked through my publication history you'd find papers across 4 major fields.
Kamaz, I tried to find your real name in order to find those papers, but it is not shown in your profile nor in the nearest source code I could find (VNCMFD). "Kamaz" alone brings up too much hits on Google. Could you please give a link to your publications?
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Old 08-04-2014, 07:49 PM   #89
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 Kamaz, I tried to find your real name in order to find those papers, but it is not shown in your profile nor in the nearest source code I could find (VNCMFD). "Kamaz" alone brings up too much hits on Google. Could you please give a link to your publications?
That's intended. I do not want my pseudonymous identity to be too easy to match to my name. Check your PM
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Old 08-04-2014, 07:53 PM   #90
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 By the way, please keep in mind that the most damaging fraudulent paper in modern science made it through peer review. Someone even managed to put a fraudulent paper into Nature.
Peer review is like a water filter. It's not 100% effective in cleaning water, but it's much better than no filter at all.
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