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[andrea]

similar results being found in several independent experiments surely adds weight to the claim. Although the NASA results really need more investigation about possible errors, because results are weird in a way that suggests some mistake.

I am eager to see if this turns out to work. It would make an huge difference in space travel. And of course a bunch of other things.

[alway]

"this thing is impossible under current scientific theories, therefore it's obviously an error in the experiment that provided the positive result"

No one is actually saying this though. The only ones suggesting it is impossible are the news media putting impossible in their headlines. It's just that technology is very complex (see also: hacky bullshit), and so we haven't necessarily worked out the hacky bullshit required to do it mathematically (though they did publish that previous paper, which supposedly aimed to do just that; though I don't know enough about that to comment on it). Out of all the potential ways to get force without propulsion mass, pushing against quantum soup would actually be one of the more plausible methods.

However, it wouldn't be of any use for atmospheric flight. Those aren't typically limited by fuel weight anyway, and with its abysmal T:W ratios, such a device would be useless there.

[andrea]

it depends... one of the articles said that some people involved think that if this thing works as they understand it, a similar device with superconductors could achieve a much higher T:W ratio. At which point, I guess it might be useful to keep stuff airborne for a long time. Maybe.

Spacecraft uses are way more straightforward and important however.

[ShadowHammer]

I have a question for you scientists. It doesn't quite fit with the manner in which this thread is being used, but I'd rather not start a new thread just for this question, and it is a science question, so I decided to post it here.
There is a set of three gears, A, B, and C.

A is twice the circumference of B, which is 1/4 the circumference of C. In other words, A=2n, B=1n, C=4n.

A is on one end of an axle, with B on the other end of the same axle. C is meshed with B.

Diagram:


When A is the input and C is the output, what is the mechanical advantage gained?
I'm pretty sure I know the answer, but I'm tired at the moment, and I don't trust myself to do anything that requires above elementary school level thinking when I'm tired. Note that this is not supposed to be a trick question.

Spoiler: What I think the answer is (click to show/hide)

I'm pretty sure it's a mechanical advantage of 4.

[Gentlefish]

It'd be 2 wouldn't it though? Even though b to c is 4, the input it a which is 2, with a final total difference of 2.

[Arx]

Yeah, it must be two, since A->B will be an advantage of 1/2, and then B->C will be an advantage of 0.5(4) = 2.

I think, anyway. Don't ask me to try to prove anything or write it according to convention.

[Sergarr]

I think it's 2, too. I'm a failure of an engineer 

[ShadowHammer]

It'd be 2 wouldn't it though? Even though b to c is 4, the input it a which is 2, with a final total difference of 2.

Yeah, it must be two, since A->B will be an advantage of 1/2, and then B->C will be an advantage of 0.5(4) = 2.

I think, anyway. Don't ask me to try to prove anything or write it according to convention.

I think it's 2, too.

Hmmm... that's what my dad said when I asked him originally, but then I pointed out that even though A is double the size of B, B still rotates once for every one rotation of A, because they are on the same axle.

Also,

can't we just use descan as the power source for our intergalactic freight

I have a heavy heart when I say that vibrating does not actually provide thrust. Unless we attach magnets to him and this drive does work, such a thing would not be feasible.

Descan may not be able to act as a power source by himself, but he could intensify the power of our intergalactic engines.

[Arx]

RIght, I missed the bit where they're on the same axle. Then it's just 1:4 so it's four, you're right.

[alway]

So here's a really interesting thing to come out of the recent SIGGRAPH conference (the annual graphics conference).
https://www.youtube.com/watch?v=FKXOucXB4a8
"The Visual Microphone: Passive Recovery of Sound from Video."

Turns out just by analyzing video sufficiently, you can see the sub-pixel vibrations well above the frequency of the recording device's 60 Hz. And recover audio from it good enough to recognize the source.

[GavJ]

That's pretty cool. Sounds just like a laser microphone in concept http://en.wikipedia.org/wiki/Laser_microphone that they used in the cold war (IIRC the design of the pentagon and some other buildings have curtain walls to stop stuff like that)

[Reelya]

So here's a really interesting thing to come out of the recent SIGGRAPH conference (the annual graphics conference).
https://www.youtube.com/watch?v=FKXOucXB4a8
"The Visual Microphone: Passive Recovery of Sound from Video."

Turns out just by analyzing video sufficiently, you can see the sub-pixel vibrations well above the frequency of the recording device's 60 Hz. And recover audio from it good enough to recognize the source.

Snoops are going to love this toy.

EDIT: thinking again, I mean snoops loved this toy and are pissed off that regular people get to play with it too now. They already had that lasers on windows reading vibration stuff to reconstruct sound, and reconstructing CRT video based on ambient light reflections off walls. They probably already know a hell of a lot of techniques that haven't filtered through to the public sphere yet.

[miauw62]

That's really cool.

[GavJ]

So here's a really interesting thing to come out of the recent SIGGRAPH conference (the annual graphics conference).
https://www.youtube.com/watch?v=FKXOucXB4a8
"The Visual Microphone: Passive Recovery of Sound from Video."

Turns out just by analyzing video sufficiently, you can see the sub-pixel vibrations well above the frequency of the recording device's 60 Hz. And recover audio from it good enough to recognize the source.

Snoops are going to love this toy.

Ehhhhh.

1) Secret audio is usually easier and cheaper to obtain than video in the first place. And easier to conceal.
2) And beyond that, you can't do this with some shitty webcam or penny sized micro cam thing. You need a rock solid damped tripod in probably a perfectly quiet and wind-less recording environment. And a bulky, decent quality resolution camera (the DSLR was on the low end and is not exactly easy to hide). The only way you could hide it would be across the street or something, which then implies the need for a massively expensive lens to magnify and resolve sufficiently.
3) Laser microphones would be significantly cheaper even from that same vantage point, and no proprietary software or whatever (very simple circuit and amp)

Seems more like a nifty piece of computer science algorithm basic science, and possibly something with applications in science measurement devices. Not so much practical surveillance methods.

[Helgoland]

What about a camera with a large optical zoom aimed at a room across the street? There's a sort of wiretap that uses a laser reflected off the window for the same purpose, but this seems easier.