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Old 12th August 2014, 08:02 PM   #121
ben m
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Originally Posted by BenBurch View Post
Response time depends on the thermal mass.
I know, but I can't imagine that their actual cavity contraption is so featherweight that it reaches equilibrium in ~5-10 seconds with a 30W heater. Maybe if there's a really lossy coupler, or a damaged RF cable, or something, that's tapping off a few watts of power and sinking it into only a gram or so of material?
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Old 12th August 2014, 09:14 PM   #122
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Originally Posted by ben m View Post
I know, but I can't imagine that their actual cavity contraption is so featherweight that it reaches equilibrium in ~5-10 seconds with a 30W heater. Maybe if there's a really lossy coupler, or a damaged RF cable, or something, that's tapping off a few watts of power and sinking it into only a gram or so of material?
So are you saying the force ramps up with time and then ramps down, over a period of seconds, as the power is switched on and then off, as opposed to switching on and off instantaneously along with the power? That is suspicious and sounds kind of "thermal" to me (warm-up and cool-down), although you might be right about the speed. BUT, perhaps something is warming up and cooling down which is not necessarily the engine itself but is still affecting the results somehow. Perhaps something changing resistance or size with a change in temperature due to applied power and that's involved making the force measurement?
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Old 12th August 2014, 10:16 PM   #123
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Originally Posted by mike3 View Post
So are you saying the force ramps up with time and then ramps down, over a period of seconds, as the power is switched on and then off, as opposed to switching on and off instantaneously along with the power?
No, the latter. The computer displays photographed in the paper suggest that the force appears "suddenly". You can't tell precisely how suddenly because (a) it's a damn photo of a damn computer screen, rather than a real plot, and (b) the measuring-arm thingee has a magnetic damper built into it which slows down the response. From the plot I'd state that force-turn-on could be anywhere between instantaneous and maybe five or ten seconds.
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Old 13th August 2014, 09:11 AM   #124
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I would like a thermal camera image. What I am thinking is that the heating that we are interested in would be on one side and likely is a thin bit of sheet metal. If the wall is thin enough it will heat almost instantly.
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Old 13th August 2014, 09:27 AM   #125
ben m
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Originally Posted by BenBurch View Post
I would like a thermal camera image. What I am thinking is that the heating that we are interested in would be on one side and likely is a thin bit of sheet metal. If the wall is thin enough it will heat almost instantly.
We're not dealing with terribly sophisticated (or well-funded) experimenters here so let's make it even easier: wrap the whole suspended apparatus (cables, "thruster", support beam, etc.) in a black plastic bag.
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Old 13th August 2014, 12:40 PM   #126
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Originally Posted by ben m View Post
We're not dealing with terribly sophisticated (or well-funded) experimenters here so let's make it even easier: wrap the whole suspended apparatus (cables, "thruster", support beam, etc.) in a black plastic bag.

Then you would claim that they were hiding something.
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Old 13th August 2014, 01:21 PM   #127
ben m
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Originally Posted by Dan O. View Post
Then you would claim that they were hiding something.
What's your problem, Dan O.? Do you remember what I said last time you made this accusation?

Originally Posted by http://www.internationalskeptics.com/forums/showthread.php?postid=10151728#post10151728
What's that about how I "wouldn't trust their analysis"? Not at all. I do not have a reason to question that the instrument readout values are what the authors claim they are. (Just as easy to believe from a real plot as from a photograph.) The question is not "did the machine move like so"; the question is whether the authors are generally skillful with this sort of test, i.e. qualified to understand and catch other errors (possibly subtle ones) in the setup. And their analysis does not give me confidence.
If I am not allowed to look at their methods-section and look for errors, why do you think papers have methods sections? The reason you publish a methods section is that people want to know if your methods were sound before they decide whether to believe your interpretation. Which is all I've been doing.

If I wanted to accuse them of fraud, why would I be brainstorming about innocent mechanical effects, like air currents and magnetic fields?
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Old 14th August 2014, 06:03 AM   #128
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You know, I work where we set up transmitters and cavities all the time... I should see if I can scrounge enough old hardware to make one... But then how to test? I can set up a torsion balance no problem, but no vacuum chamber.
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