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Old 05-05-2015, 08:26 PM   #211
kamaz
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Quote:
Originally Posted by jedidia View Post
 You're forgetting the third option: The device might work, but for completely different reasons than originally assumed. Reasons that might not violate known physics quite as much.
But we're there already. The original inventor's theory of operation was equivalent to pulling yourself up by your shoelaces. The current conjectures about quantum vacuum, space warping and (my favorite) Casimir effect, may sound sci-fi, but at least do not seems to be expressly forbidden. And they are falsifiable, so experiments can be performed to verify them.

---------- Post added at 09:03 PM ---------- Previous post was at 08:50 PM ----------

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Originally Posted by Urwumpe View Post
 Wrong. Try again. Maybe you are not knowing a known theory, that applies, but thats just you. (and its the point, where I would like to summon Fizyk into the thread)
Enlighten me

---------- Post added at 09:26 PM ---------- Previous post was at 09:03 PM ----------

Review paper: http://www.slideshare.net/KurtZeller...41315-46946953 ...from which we learn that Northwestern Polytechnic University is also seeing thrust. Well, well, well. The plot thickens.

And this is just gorgeous:

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Old 05-05-2015, 08:44 PM   #212
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Originally Posted by kamaz View Post
 Enlighten me
BTW... do I read their plot correctly that they actually measured a change of 2.4 mm over 5 cm distance? (4000 wavelengths of the laser)

Also, despite the claims of the scientists, the existence of air in the test path does not go away by them claiming that the effect by just heating the air is 40 times smaller than the measurement - because their justification also contains: The smallest we can measure at all, as theoretical limit, is 40 times bigger than possible by heating the air by 30 W.
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Old 05-05-2015, 09:03 PM   #213
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No, you don't. This is an FFT plot of CCD pixel data. I usually rescale FFTs so the maximum is 1. Less confusing this way. You are looking for relative values anyway.

Measuring 2.4mm displacement does not require interferometers

The displacement value can be back-calculated from his error analysis: he's saying that he has ~1/100th wavelength precision, He-Ne wavelength is 633nm, thus ~6.3nm noise... times 40 gives ~252nm displacement.

Last edited by kamaz; 05-05-2015 at 09:07 PM.
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Old 05-05-2015, 09:06 PM   #214
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I don't know... the paper you posted isn't all that convincing.

Including the data that says more thrust was produced from a 2.6 W input than at 15+W.

This seems like another case of FTL neutrinos to me.

I wish it would work. I really do. We'd finally get somewhere in space...
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Old 05-05-2015, 09:08 PM   #215
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Quote:
Originally Posted by kamaz View Post
 No, you don't. This is an FFT plot of CCD pixel data. I usually rescale FFTs so the maximum is 1. Less confusing this way. You are looking for relative values anyway.

Measuring 2.4mm displacement does not require interferometers

The displacement value can be back-calculated from his error analysis: he's saying that he has ~1/100th wavelength precision, He-Ne wavelength is 633nm, thus ~6.3nm noise... times 40 gives ~252nm displacement.
No, I mean the other plot, that was using some physical dimension from 0 to 10000 without any units and called it displacement.
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Old 05-05-2015, 09:22 PM   #216
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Originally Posted by Urwumpe View Post
 No, I mean the other plot, that was using some physical dimension from 0 to 10000 without any units and called it displacement.
Ah, that one:



Yes, that gave me pause as well.

On a second thought, makes sense. An interferometer will only measure displacement up to one wavelength so the maximum is 633nm. (If path length is x wavelengths, it reads out x-floor(x)). From the color, the graph peaks are around 40% full scale, which corresponds to 250nm, which is the same value as he uses in his noise analysis (noise = 1% full scale, signal = 40*noise = 40% full scale).

Also: graph apparently done in Matlab using default settings

Last edited by kamaz; 05-05-2015 at 09:28 PM.
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Old 05-11-2015, 12:42 PM   #217
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NASA seems to want everyone take it with a grain of salt, too: http://www.space.com/29363-impossibl...e87cca4901d98e

I wonder what it would cost them - in both terms of credibility and finance - to build an experiment and run it in space. Let's say it really stays "mysterious", how long do you think would it take them to send something up and test it? 2 years?
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Old 05-11-2015, 01:53 PM   #218
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2 years is optimistic IMO, I say 5 at the least 15 if we are being realistic, and no outside party intervenes.
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Old 05-11-2015, 02:26 PM   #219
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Politics. The management distances themselves from the project so they are not dragged down in case it fails.

It makes no sense to launch this into space at this point. If the effect is confirmed, people everywhere will start copying this and optimizing the design, which, logically, should result in increased thrust. (Remember, at this point nobody really knows how the gizmo works, so it's extremely unlikely that the current design has no room for improvement.)

---------- Post added at 03:26 PM ---------- Previous post was at 03:20 PM ----------

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Originally Posted by Hlynkacg View Post
 2 years is optimistic IMO, I say 5 at the least 15 if we are being realistic, and no outside party intervenes.
Hard to say. It can be everywhere from 1 year to infinity depending on how hard it is to make the gizmo work reliably.
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Old 05-11-2015, 04:18 PM   #220
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6 months and a day, if they just launch it as experiment on a sounding rocket - those are very flexible in terms of mission design, cheap enough to launch experiments even as private company and offer enough payload capacity and minutes of microgravity for a short test.

The biggest challenge would just be a precise enough experiment setup to measure such a low thrust in a few minutes of microgravity.

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Old 05-12-2015, 01:15 PM   #221
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Not sure if this has been posted or already discussed but here's an article:

http://www.researchgate.net/publicat...HANICAL_EFFECT

It dates from last year may or may not be helpful.
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Old 05-12-2015, 02:31 PM   #222
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Quote:
Originally Posted by Urwumpe View Post
 6 months and a day, if they just launch it as experiment on a sounding rocket - those are very flexible in terms of mission design, cheap enough to launch experiments even as private company and offer enough payload capacity and minutes of microgravity for a short test.

The biggest challenge would just be a precise enough experiment setup to measure such a low thrust in a few minutes of microgravity.
I'm not understanding how you would pick out a few, what, micronewtons of thrust from the micro drag in a few minutes of fire time. Have ion engines ever been tested using sounding rockets?
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Old 05-12-2015, 04:02 PM   #223
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Originally Posted by boogabooga View Post
 I'm not understanding how you would pick out a few, what, micronewtons of thrust from the micro drag in a few minutes of fire time. Have ion engines ever been tested using sounding rockets?
Actually - yes. The ESRO has conducted such flights in the 1970s, as precursor of ESA.

But the primary tests of earlier devices had been as experiment on engineering satellites, before a mission finally relied on them as primary propulsion system.

Remember: A "few minutes of fire time" means about 10 minutes of microgravity for a 450 km launch, the record had been about 20 minutes of microgravity for a small payload.

Since electric propulsion systems have even been tested in free-fall towers with mere seconds of microgravity, hardly surprising.
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Old 05-13-2015, 05:46 PM   #224
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Attempt at independent replication:

http://www.masinaelectrica.com/emdri...ependent-test/

Null result (so far).
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Old 05-13-2015, 06:58 PM   #225
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Quote:
After power on for 40 sec temperature was 85 degree Celsius.
He pumped 800 W of power into the damn thing. Of course it heats up
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