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The warp drive will have to wait

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Re: The warp drive will have to wait

#2

Post by dmichulke »

https://translate.google.com/translate?hl=en&ie=UTF8&prev=_t...

The critical passages - translated by myself

Page 2:

The hint:

"Again it showed the same behavior - until the drive was directed towards the top for testing purposes. Usually, the drive is put on a torsion balance in a way that it can best turn the scale left or right. With the drive directed towards the top nothing should be measurable. [...] However, the drive directed toward the top in this experiment still showed the same force as when directed to the left."

The test result at TU Dresden, Germany: "Tjalmar said: 'I can't say I proved or refuted the EM drive'" (because they didn't have the means to test it with a battery instead of an external power supply)

Reference to a follow-up from a Chinese university: "But a research group from China did the necessary to refute it. As soon as the EM drive doesn't get its power from a cable outside [i.e., it get's its power from a battery], there is no measurable force anymore."

The link to the Chinese paper http://www.tjjs.casic.cn/ch/reader/create_pdf.aspx?file_no=2...

The final sentence of the abstract: "Within the measuring range of three-wire torsion pendulum thrust measurement system，the independent microwave thruster propulsion device did not detect significant thrust. Measurement results fluctuate within ± 0.7mN range under the conditions 230W microwave power output，and the relative uncertainty is greater than 80%"

Re: The warp drive will have to wait

#4

Post by aargh_aargh »

dmichulke wrote: post #2

https://translate.google.com/translate?hl=en&ie=UTF8&prev=_t... The critical passages - translated by myself Page 2: The hint: "Again it showed the same behavior - until the drive was directed towards the top for testing purposes. Usually, the drive is put on a torsion balance in a way that it can best turn the scale left or right. With the drive directed towards the top nothing should be measurable. [...] However, t…

So... you're saying all we need to do is pull an extension cord behind our spacecraft?

Unlimited powahhh!

Re: The warp drive will have to wait

#5

Post by chris_wot »

aargh_aargh wrote: post #4
dmichulke wrote: post #2

https://translate.google.com/translate?hl=en&ie=UTF8&prev=_t... The critical passages - translated by myself Page 2: The hint: "Again it showed the same behavior - until the drive was directed towards the top for testing purposes. Usually, the drive is put on a torsion balance in a way that it can best turn the scale left or right. With the drive directed towards the top nothing should be measurable. [...] However, t…

So... you're saying all we need to do is pull an extension cord behind our spacecraft? Unlimited powahhh!

Sort of like an electric mower with a power cord?

Re: The warp drive will have to wait

#6

Post by Tomte »

I think the best sentence is this:

"The theoretical expectation is that you don't measure anything. Now you're measuring something, and you can learn extremely much on this hunt for the error."

Re: The warp drive will have to wait

#7

Post by bayesian_horse »

bleuarff wrote: post #3

I guess a cheap and efficient propulsion that doesn't fit our understanding of physics was too good to be true. Still, it's a bit sad, that would have been beautiful if it were true.

As far as I understand it, it's not quite over yet. Maybe the refusal itself can't be replicated by the other groups. Now that will keep these physicists busy for a while...

Re: The warp drive will have to wait

#9

Post by jerf »

aargh_aargh wrote: post #4
dmichulke wrote: post #2

https://translate.google.com/translate?hl=en&ie=UTF8&prev=_t... The critical passages - translated by myself Page 2: The hint: "Again it showed the same behavior - until the drive was directed towards the top for testing purposes. Usually, the drive is put on a torsion balance in a way that it can best turn the scale left or right. With the drive directed towards the top nothing should be measurable. [...] However, t…

So... you're saying all we need to do is pull an extension cord behind our spacecraft? Unlimited powahhh!

That's basically the thinking behind the laser-propulsion plan. The rocket equation gets a lot less hostile when the engine is not mounted on the rocket, but that has its own practical issues. Less than trying to drag a literal cord, of course.
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