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Quantum vacuum plasma thruster

en.wikipedia.org

1–10 of 26 posts

Re: Quantum vacuum plasma thruster

#4
Basically a plausible sounding mechanic for "thrusters" from Larry Niven's Known Space. Lots of Sci-Fi ships as portrayed in media would be implausible if they actually had to carry reaction mass. Even antimatter fueled ships need mass fractions over 50% for intra-solar system missions. (Up to 80%, but for some reason, never over 80%. Robert Forward covered this in Mirror Matter)

One thing I'm confused over, however, is what happens to the momentum? Is this like magically creating particles that carry momentum? (So you can carry momentum in the opposite direction.)

Re: Quantum vacuum plasma thruster

#5
This reference looks interesting:

"A net unidirectional and reversible force on the order of ± 3.14 milli‐Newton or 0.069% of the suspended test article mass was recorded by us in our first high frequency 2.2 MHz test article. The authors also developed a W‐E model that integrates the various engineering parameters affecting the design, construction, and performance of W‐E based MLTs for the next generation of systems. When Woodward’s (2004a, 2004b, 2005) and our test results were compared with the model’s predictions, the test results exceeded predictions by one to two orders of magnitude. Efforts are underway to understand the discrepancies and update the model. The test results imply that these devices, when fully developed, could be competitive with ion engines intended for use on satellite station keeping and/or orbital transfers."

http://scitation.aip.org/content/aip/proceeding/aipcp/10.106...

Re: Quantum vacuum plasma thruster

#7
> equivalent specific impulse of ~1x10^12 seconds

this is so much more than pretty much anything else it's hard to comprehend why there hasn't been a billion dollars put into it just to rule out the possibility that it could work.

Re: Quantum vacuum plasma thruster

#8

This sounds a lot like a perpetual motion machine...

No, one still needs energy to accelerate the particles to actually create an impulse. Think of it as a (propeller) airplane, but instead of accelerating air, it uses the quasiparticles due to vacuum fluctuations.

Re: Quantum vacuum plasma thruster

#9

This sounds a lot like a perpetual motion machine...

Did you even read the article or just feel like spamming HN with some uninformed snarky comment? I also am skeptical about this and don't fully understand the physics behind it. But I did RTFA and all of the references checked out.

Re: Quantum vacuum plasma thruster

#10
post #7

> equivalent specific impulse of ~1x10^12 seconds this is so much more than pretty much anything else it's hard to comprehend why there hasn't been a billion dollars put into it just to rule out the possibility that it could work.

Most likely because of the 0.1N/kW. The best current made RTG's generate about 2.8 watts per kilogram. [source Wikipedia]

Which means based on these current numbers well need 3500 kilograms per Newton of thrusts. This would generate a acceleration of 0.00002 m/s^2 of acceleration. This would take about an hour, and a half to make a 1m/s delta-v course change.

And that's without the drive, communication, heating, or scientific instruments. The drive is VERY low powered. Also specific impulse means little if you don't have fuel, since it determines your efficiency, but this rocket already has 100% efficiency since it has no on-board fuel.

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