1404: Quantum Vacuum Virtual Plasma

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1404: Quantum Vacuum Virtual Plasma

Postby Eebster the Great » Wed Aug 06, 2014 4:34 am UTC

Image
Alt text: "I don't understand the things you do, and you therefore may represent an interaction with the quantum vacuum virtual plasma."


Frankly I doubt the validity of all these tests. None of the explanations so far are even close to adequate, and they haven't been peer-reviewed yet. But it's an intriguing idea.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby SomeoneSomewhere » Wed Aug 06, 2014 4:42 am UTC

I'm having trouble finding info on how long this was sustained for...

720 millinewtons is a little more than the weight of a tennis ball. That's not particularly small.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Eebster the Great » Wed Aug 06, 2014 4:46 am UTC

The NASA tests didn't produce 720 mN but 116 µN peak. That's pretty small, but still 10 to 100 times the sensitivity of the torsion balance they were using.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby rhomboidal » Wed Aug 06, 2014 4:47 am UTC

"Quantum Vacuum Virtual Plasma" is my favorite German Trance group. Great for raving. And twisting the laws of physics to.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby wing gundam » Wed Aug 06, 2014 5:20 am UTC

So 20kW / (935 MHz * h) ≈≈ 3*10^28 photons, 20kW / c ≈≈ 67µN. That's the total output of the magnetron. It's about the order of what NASA reported. But all those photons clearly aren't escaping to infinity.

The inventor also posted a theory, but apparently it's spam.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby overwatch » Wed Aug 06, 2014 6:01 am UTC

This is the first time I saw a badly researched XKCD strip.

According to the report(*), the test article didn't "twitch" but produced continuous thrust (each test "firing" was 30 seconds long) of up to 91 µN.

They also didn't "pump 20 kW" anywhere - it peaked at a mere 28 W.

(*) I can't seem to be able to link the report here because "This message was flagged as spam and has been denied." ... great.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby bachaddict » Wed Aug 06, 2014 6:08 am UTC

wing gundam wrote:So 20kW / (935 MHz * h) ≈≈ 3*10^28 photons, 20kW / c ≈≈ 67µN. That's the total output of the magnetron. It's about the order of what NASA reported. But all those photons clearly aren't escaping to infinity.

The inventor also posted a theory, but apparently it's spam.


Read the forum rules, then add the URL with spaces after dots :)
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Neil_Boekend » Wed Aug 06, 2014 6:09 am UTC

They weren't testing it in vacuum. 40-80 µN doesn't require a lot of air movement and 20 kW microwave radiation can cause a lot of air movement. The control that shouldn't have produced thrust did also produce thrust.
It would have been cool. Even a small force is useful in space. It wouldn't have gotten you to space but interstellar probes become far more feasible with reactionless drives.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby overwatch » Wed Aug 06, 2014 6:13 am UTC

Neil_Boekend wrote:The control that shouldn't have produced thrust did also produce thrust.


Not true - they used two designs, one of them shouldn't produce any thrust but did (albeit less).

The control (a resistive load) did produce no thrust.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Rufaellie » Wed Aug 06, 2014 6:18 am UTC

This is one of those where if I did get it, I'd be all like: "ZING!"

As it is I'm like "errrrrmkay"
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby phlip » Wed Aug 06, 2014 6:23 am UTC

bachaddict wrote:add the URL with spaces after dots :)

I'd really rather if you didn't. Tricking the forum software into thinking you didn't post a link doesn't get you around the "don't post links if you're new" rule. It just means we need to clean up after you by hand, instead.

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enum ಠ_ಠ {°□°╰=1, °Д°╰, ಠ益ಠ╰};
void ┻━┻︵​╰(ಠ_ಠ ⚠) {exit((int)⚠);}
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Neil_Boekend » Wed Aug 06, 2014 6:40 am UTC

overwatch wrote:
Neil_Boekend wrote:The control that shouldn't have produced thrust did also produce thrust.


Not true - they used two designs, one of them shouldn't produce any thrust but did (albeit less).

The control (a resistive load) did produce no thrust.

I didn't know there was a resistive load control. It was not in the info I read about it.
I meant the second design that shouldn't have produced thrust.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby keithl » Wed Aug 06, 2014 7:03 am UTC

It probably emits superluminal neutrinos, causing neutronless fusion in deuterated palladium resulting in ether drag and anomalous acceleration of the Voyager spacecraft.

There are so many ways to make micronewtons - magnetic fields in feed conductors, P/c optical pressure from heat, induction from AC magnetic fields, hot air currents - and ways to make the appearance of micronewtons, such as differential heating in a suspension system. Nature does her accounting more accurately than most experimenters. The name for an effect that gets smaller the more carefully you measure it is "error".

Given that this an invention of someone seeking money from the government, subtle legerdemaine is more probable than new physics. Before NASA writes any checks, bring in Penn and Teller and James Randi. NASA is fooled by a lot of stuff, they should have some professional debunkers on speed-dial.

But then, maybe I am too lazy to add new terms to my force calculations.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Eebster the Great » Wed Aug 06, 2014 7:40 am UTC

overwatch wrote:This is the first time I saw a badly researched XKCD strip.

According to the report(*), the test article didn't "twitch" but produced continuous thrust (each test "firing" was 30 seconds long) of up to 91 µN.

I believe "twitch" is not a technical term.

They also didn't "pump 20 kW" anywhere - it peaked at a mere 28 W.

There were several relevant studies. One Chinese study claimed to produce 720 mN from 2.5 kW. I haven't found where the 20 kW figure comes from though. Does anybody else know?

(By the way, gizmag claims this study was peer-reviewed. Does anyone know about the peer-review standards in China? Are they comparable to the U.S.?)

(*) I can't seem to be able to link the report here because "This message was flagged as spam and has been denied." ... great.

As explained ITT, you need ten posts before you can post links. That's presumably mainly to avoid spam.

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NOW IF YOU'LL EXCUSE ME, I HAVE TURTLEMOLPIES TO BLITZNAP

Postby Eternal Density » Wed Aug 06, 2014 10:53 am UTC

My first reaction to the titletext: "Awww that's so sweet."
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby CapCouillon » Wed Aug 06, 2014 11:45 am UTC

Once again I would like to thank Mr. Munroe for making me late for work... I mean how can you pass up investigation of a device who's parent company is named after a clasic Star Trek line?
I mean really,,, name your company Cannae ("Ye canna change the laws of physics, Cap'n!" -- Scotty ) ? Not to mention the phrase "Quantum Vacuum Virtual Plasma" just makes my fingers itch for a little google-fu.

Now, an hour later, I don't understand anymore than I did when I started. Seems NASA has the same problem (NASA Paper: Anomalous Thrust Production from an RF Test Device Measured on a Low-Thrust Torsion Pendulum) Of course, we really don't understand the analgesic mechanism of asprin (or willow bark for that matter) but it works. Curiosity and all that.

As long as I am already late, time to investigate how many Lac bugs it takes to make a kilo of shellac (50,000 to 300,000 depending on who your source is) and whether they use free-range Lac bugs, or if there are Lac bug ranches (Do they use horse-flys to round up the Lac bugs?) This discussion actually came up in the shop yesterday, and the information may actually distract them from my somewhat tardy arrival.

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Re: NOW IF YOU'LL EXCUSE ME, I HAVE TURTLEMOLPIES TO BLITZNA

Postby cellocgw » Wed Aug 06, 2014 12:27 pm UTC

Eternal Density wrote:My first reaction to the titletext: "Awww that's so sweet."
Is there something wrong with me?

There certainly is, but not in a mustardly way. And we all love you just the way you are (cue the string section) :D
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby AEB » Wed Aug 06, 2014 1:19 pm UTC

This bears repeating:
keithl wrote:The name for an effect that gets smaller the more carefully you measure it is "error".

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby richP » Wed Aug 06, 2014 1:53 pm UTC

What's the over/under for the number of posts before the tinfoil hat crowd shows up discussing infinite sources of energy that *they* are hiding from us?

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Re: 1404: Quantum Vacuum Virtual Plasma is spam in SPAAAAACE

Postby airdrik » Wed Aug 06, 2014 2:32 pm UTC

bachaddict wrote:
wing gundam wrote:So 20kW / (935 MHz * h) ≈≈ 3*10^28 photons, 20kW / c ≈≈ 67µN. That's the total output of the magnetron. It's about the order of what NASA reported. But all those photons clearly aren't escaping to infinity.

The inventor also posted a theory, but apparently it's spam.


Read the forum rules, then add the URL with spaces after dots :)

When I read that, I just assumed that wing gundam was saying that someone like NASA or other reputable entity had looked at the theory and dismissed it as spam. Much more entertaining to think that than just that wing gundam's post with the url was marked as spam because he doesn't have enough posts.

richP wrote:What's the over/under for the number of posts before the tinfoil hat crowd shows up discussing infinite sources of energy that *they* are hiding from us?

Like the infinite reserve of methane created by geologic processes?
Well at least this theory has the potential to work outside of the earth's atmosphere+magnetosphere.

Edit: cleaned up url
Last edited by airdrik on Fri Aug 08, 2014 4:57 pm UTC, edited 1 time in total.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby San Fran Sam » Wed Aug 06, 2014 3:02 pm UTC

"I need more power Mr. Scott!"
"I canna get any more power Cap'n. The Quantum Vacuum Virtual Plasma drive is about to implode."
"The what is about to what?"
"I donna know, Cap'n, but it sounded good."

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby schapel » Wed Aug 06, 2014 3:21 pm UTC

Eebster the Great wrote:I believe "twitch" is not a technical term.

In that case, I propose we use the term "twitch" for the seventh derivative of position!
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Quizatzhaderac » Wed Aug 06, 2014 3:33 pm UTC

NASA wrote:...within a stainless steel vacuum chamber with the door closed but at ambient atmospheric pressure.
So they tested it in a vacuum chamber, but didn't test it in a vacuum? I may not understand important logistics of vacuum chambers, but it seems like they went through 90% of the effort of testing in a vacuum for 10% of the gain.
schapel wrote:
Eebster the Great wrote:I believe "twitch" is not a technical term.

In that case, I propose we use the term "twitch" for the seventh derivative of position!
http://math.ucr.edu/home/baez/physics/General/jerk.html
I vote for second moment of the first time derivative of position.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby inio » Wed Aug 06, 2014 4:06 pm UTC

From the full report (which I acquired from 4chan of all places. Sorry, thread has expired.):

During test run data takes at vacuum, the turbo pumps continue to run to maintain the hard vacuum environment. The high-frequency vibrations from the turbo pump have no noticeable effect on the testing seismic environment.


So no issue there. Here's a little more detail on the real null test as well:

Null testing is performed by attaching the RF drive system to a 50 ohm load and running the system at full power. The null force testing indicated that there was an average null force of 9.6 micronewtons present in the as tested configuration. The presence of this null force was a result of the DC power current of 5.6 amps running in the power cable to the RF amplifier from the liquid metal contacts. This current causes the power cable to generate a magnetic field that interacts with the torsion pendulum magnetic damper system.


To summarize their results (even giving one significant digit on these is being generous):
Cannae asymmetric "slotted": 40µN @ 28W
Cannae symmetric (was supposed to be non-functional): 20-40µN @ 28W
Tapered cone @ 1932.6MHz: 90µN @ 17W
Tapered cone @ 1936.7MHz: 50µN @ 17W
Tapered cone @ 1880.4MHz: 50µN @ 2.6W
50Ω resistor: 10µN @ 28W

Overall my takeaway from the report is that either whoever was doing it was crazy rushed, or was an undergrad intern. A few issues with it:
  • Despite only taking a few minutes per test, with several hours to change configurations due to vacuum pump-down, each configuration was run a different, small number of times (varying from 1 to 5)
  • They include their "results" in the form of pictures of oscilloscope screens with lines drawn onto them (imgur dot com slash m7gsi6C)
  • As far as I can tell no effort was made to reduce the bias due to DC current flow to the amplifier by e.g. twisting the power lines.
  • No mention of measuring common-mode output of the amplifier, which through electrostatic effects could be biasing the measurement
  • No attempt to build a resonant test load which has no possible reason to create any thrust (e.g. a non-tapered cylinder with tap at the center)

My hope is that this paper finally gets someone adept at doing this type of research to study and debunk (or maybe prove!) these things. There is definitely something non-obvious going on here, but the NASA paper makes me only slightly less skeptical that it is truly anomalous thrust.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby gmalivuk » Wed Aug 06, 2014 5:51 pm UTC

AEB wrote:This bears repeating:
keithl wrote:The name for an effect that gets smaller the more carefully you measure it is "error".

Especially when those more careful measurements start showing the effect in the control as well. At the very least, it means the designer doesn't know what's really going on. (See also: "confirmations" of acupuncture that show the same effect with toothpicks or other sham versions. If acupuncture were real and worked anything like proponents describe it, sticking needles in with complete disregard for meridians shouldn't work, or at the very least shouldn't have nearly the same effect size.)
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Mikeski » Wed Aug 06, 2014 6:58 pm UTC

"Quantum Vacuum Virtual Plasma"

...I guess the change-your-password window popped up. It's not "Correct Horse Battery Staple" anymore.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby BlitzGirl » Wed Aug 06, 2014 7:55 pm UTC

Quantum Horse Battery Plasma
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby rndmplyr » Wed Aug 06, 2014 8:32 pm UTC

I want to believe!
It would complicate some equations and give some (many) people headaches, but thrusting satellites or probes without exhaust would be great.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby gmalivuk » Wed Aug 06, 2014 9:37 pm UTC

It wouldn't just "complicate" some equations, though. It would imply that the most fundamental laws of the universe change from one place to another.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Eebster the Great » Wed Aug 06, 2014 10:27 pm UTC

Well the inventor insists conservation of momentum is not violated and that it is an open system, so in that case it wouldn't mean the laws of physics would depend on your position in the universe.

Alternatively, momentum is not conserved in warped spacetime (since in a sense the laws of physics do change with position), so maybe he just invented warp drive.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby DracMonster » Wed Aug 06, 2014 10:46 pm UTC

"Ooh, baby, pump 20 hot, thick, sweaty kilowatts into me and I'll do a lot more than twitch for you!"

Seriously, the Freud rating of the last panel is off the charts.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby gmalivuk » Thu Aug 07, 2014 12:34 am UTC

No, if any Freud rating is off the charts, it's the one for your post. The last panel of the comic is easily read as being about electrocution by anyone not already thinking about sex.

Eebster the Great wrote:Well the inventor insists conservation of momentum is not violated
Well yeah, but inventors always insist that their purported inventions aren't physically impossible.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Eebster the Great » Thu Aug 07, 2014 12:39 am UTC

gmalivuk wrote:
Eebster the Great wrote:Well the inventor insists conservation of momentum is not violated
Well yeah, but inventors always insist that their purported inventions aren't physically impossible.

True, but I still prefer this approach to claiming that the engine does violate conservation of momentum (and/or energy), but that this is still possible, which is what we usually see with "free energy" hacks and the like.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby cryptoengineer » Thu Aug 07, 2014 1:31 am UTC

Its worth looking at the Wikipedia article on the issue:
http://en.wikipedia.org/wiki/Quantum_va ... a_thruster
It explains why, if it works according to the claim, it doesn't violate
conservation of momentum. To a first approximation, its an MHD
drive using the Dirac Sea of virtual particles as it's working medium.

Powerboats and airplanes accelerate themselves in a similar way - finding
a way to accelerate the medium in which the live to the back.

I'd like to see this work, but my money is on the anomalous thrust seen
being due to experimental error.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby drachefly » Thu Aug 07, 2014 3:50 pm UTC

cryptoengineer wrote:Its worth looking at the Wikipedia article on the issue:
http://en.wikipedia.org/wiki/Quantum_va ... a_thruster
It explains why, if it works according to the claim, it doesn't violate
conservation of momentum. To a first approximation, its an MHD
drive using the Dirac Sea of virtual particles as it's working medium.

Powerboats and airplanes accelerate themselves in a similar way - finding
a way to accelerate the medium in which the live to the back.

I'd like to see this work, but my money is on the anomalous thrust seen
being due to experimental error.



But to push off the Dirac Sea, you need to make the ones you're pushing off of not be virtual anymore. If you're pushing off of nothing, you're violating QM so hard that tweaks aren't going to do it - you need to just go make a new theory.

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Pfhorrest » Thu Aug 07, 2014 5:20 pm UTC

Event horizons turn some virtual particles into real particles, which is where Hawking radiation comes from.

If somehow such an effect were possible to create in one direction, rather than radially all around -- some kind of Hawking radiation beam, essentially -- wouldn't the radiation pressure from that propel the object emitting it?

Or alternately, if a radial source of Hawking radiation (like a black hole) were somehow contained and all its radiation deflected in one direction, like how a rocket contains and directs the outward force of an explosion, would that not be a similar source of "reactionless" propulsion? It's not actually reactionless of course but it doesn't require you to carry a working medium with you… although I guess you would be diminishing the mass of the black hole equivalent in the process, so that kinda becomes your working medium….
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby speising » Thu Aug 07, 2014 5:47 pm UTC

if you manage to separate the particle pairs, accelerate them, and let them recombine in the exhaust (similar to how ion drives work), that shouldn't be a conservation problem, should it?

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Re: 1404: Quantum Vacuum Virtual Plasma

Postby gmalivuk » Thu Aug 07, 2014 5:55 pm UTC

Pfhorrest wrote:although I guess you would be diminishing the mass of the black hole equivalent in the process, so that kinda becomes your working medium….

Yeah, it's just a fancy type of matter-conversion photon drive, with all the same mass ratios and such you always get from the rocket equation.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Pfhorrest » Thu Aug 07, 2014 6:12 pm UTC

speising wrote:if you manage to separate the particle pairs, accelerate them, and let them recombine in the exhaust (similar to how ion drives work), that shouldn't be a conservation problem, should it?

But how would you act upon the virtual particles without realizing one of them, requiring that you annihilate the other, thus negating the mass of something in the process, which something is then effectively your reaction mass?

If you could somehow force both of them to be real, and then let them recombine (annihilate), you would get a burst of energy out of that reaction, and that energy must have come from somewhere, namely the same energy that was negated to force them both into reality. You could negate a virtual electron to realize a real positron, and negate a virtual positron to realize a real electron, then accelerate them both and let them recombine and annihilate in the exhaust... or just let them recombine in place and use the explosive force as propulsion. But then whatever you're negating the virtual particles against is effectively your fuel, as you would deplete it to accomplish the effect.

On the other hand, if negative mass is possible, and there was some way to realize one of a virtual particle pair by realizing the other with negative mass, then... you would have effectively invented warp drive.
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Re: 1404: Quantum Vacuum Virtual Plasma

Postby Quizatzhaderac » Thu Aug 07, 2014 6:23 pm UTC

<boring>My money is on it being an anomalous test result</boring>
Eebster the Great wrote:
gmalivuk wrote:
Eebster the Great wrote:Well the inventor insists conservation of momentum is not violated
Well yeah, but inventors always insist that their purported inventions aren't physically impossible.

True, but I still prefer this approach to claiming that the engine does violate conservation of momentum (and/or energy), but that this is still possible, which is what we usually see with "free energy" hacks and the like.
Well it's important to realize there are (effectively) two separate basic claims being made here.

1) This device will generate thrust, in a (realistic) vacuum, without (intentionally) supplying it's own reaction mass.
2) Quantum vacuum fluctuations can be used as reaction mass.

Two might follow very weakly from one, but people are really hesitant to believe something happens without a mechanism.

Now, does one violate newton's laws? The obvious answer is yes, but people have looked foolish assuming nearly that before, so the question is "can we exhaustively eliminate all momentum reactions?" the answer is probably, but not certainly.

As for two, it sounds wonderful and suspicious and like we may be around the corner from a mathematical proof that it's impossible. However I have to humbly admit that I'm not a physicist.
drachefly wrote:But to push off the Dirac Sea, you need to make the ones you're pushing off of not be virtual anymore. If you're pushing off of nothing, you're violating QM so hard that tweaks aren't going to do it - you need to just go make a new theory.
That's how Coulomb's law works if you want to keep locality: one charge pulls/pushes off a virtual particle, which travels and then pulls/pushes off the other charge; measuring it as a photon makes it not virtual.
Last edited by Quizatzhaderac on Wed Apr 20, 2016 8:49 pm UTC, edited 1 time in total.
The thing about recursion problems is that they tend to contain other recursion problems.


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