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Author Topic: NASA confirms - new engine has apparently broken physics.  (Read 4507 times)

Desiderya

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #30 on: 04 Aug 2014, 12:33 »

(16) shows the relation between Q-factors and velocity, nothing more. The relevant assumptions - those I've asked you to explain - are a bit higher up. To answer my own question, however, as you're possibily a wee bit out of your depths here.

You see the net power loss directly being transformed into kinetic energy (velocity), essentially making this device magical. There is, of course, a correction factor for his device (Df), which is a bit concerning giving what he's trying to prove. All the complicated maths up and including this point are correct as far as I'm able to check them (I'm sure you did work through all of them on paper, too), and even some of his assumptions are reasonable.
There are some jarring mistakes, however, and anyone with some high school physics classes should've been able to spot them. To be fair, in his most recent version of the theory paper (9.4) they've been cut - not replaced or corrected, cut. So you might've missed the opportunity to reflect on them.

v9.3 [1] still has them.



So, all his fancy math proves that his EM waves push harder on the top than on the bottom if he uses the cone shaped apparatus. He, however, neglects a bit of the aforementioned high-school physics. Inelastic collisions always have a force component perpendicular to the resulting vectors. In other words, the EM waves do not just push on the top and bottom of the cavity, but also on the sides, resulting in a net downward push (do some vector analysis on a sketch to see it, it's really simple). You will see that this cancels the top/bottom difference out. He made the same mistake in his paper again, even in 9.4 p.4, when he imagines the system with a fluid instead of microwaves, discarding the push on the sides as a mere mechanical strain.



If you would've used your own head instead of quoting Shawyer's own FAQ you might've spotted that.

It's impossible to do a proper survey of Shawyer's own measurements as there's no documentation and/or data published, which is not a good sign, as
a proper publication has the supporting information providing enough information to properly judge the procedures used in testing. The Eagleworks lab shared a bit more information, which is still not very good based on a few reasons I've already given. Let's rehash them.

1) They've measured 3.6mN on a scale with a single digit mN resolution.
2) They've measured the same net force on the active and 'inactive' device, which despite the flaws in the setup, strongly suggest that they might've gotten the same results if they put a potato in their test chamber.
3) They've measured at ambient pressure. Even a very small temperature gradient between the device and the atmosphere will lead to air convection exerting tiny pressures (mN!), too.
4) The devices are bulky and use active water cooling for their magnetrons, also a lot of cables. We're trying to talk about mN effects - the FTL experiment's error was a bad plug/connector, not a groundbreaking effect.


The 'ass in seat' example was an attempt to make an easy to understand example why conservation of momentum is violated. Real-life examples don't hold up well with quantum mechanical systems, however, just saying "quantum" and wave your hand doesn't help either (neither does saying 'relativistic' or 'Einstein'). Conservation of energy/momentum holds up in QM, which just shows how passé Newtonian mechanics really are.
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PracticalTechnicality

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #31 on: 04 Aug 2014, 12:56 »

Having followed this thread for a while, I cannot like Desiderya's response enough.  Do we have medals for good posting here?
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Esna Pitoojee

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #32 on: 07 Aug 2014, 19:34 »

Some questions about the tests answered.

Must. Resist. Urge. To. Get. Excited.
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orange

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #33 on: 09 Aug 2014, 10:42 »

Quote
91 micronewtons of thrust for 17 watts of power, compared to the 40 micronewtons of thrust from 28 watts for the Cannae drive.

Takes forever to get anywhere.  Small solar sails are as effective in the inner solar system.

People keep chasing "special" technology like there is a holy grail to open up space colonization/development, but keep forgetting that it isn't moving around space that is the problem.  It is getting into space that is the challenge, but even that already has a brute force solution that works.  The cost of space is not tied to the technology.  It is tied to the number of engineers & technicians needed to do the work.
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Saede Riordan

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #34 on: 16 Aug 2014, 11:58 »

Quote
91 micronewtons of thrust for 17 watts of power, compared to the 40 micronewtons of thrust from 28 watts for the Cannae drive.

Takes forever to get anywhere.  Small solar sails are as effective in the inner solar system.

People keep chasing "special" technology like there is a holy grail to open up space colonization/development, but keep forgetting that it isn't moving around space that is the problem.  It is getting into space that is the challenge, but even that already has a brute force solution that works.  The cost of space is not tied to the technology.  It is tied to the number of engineers & technicians needed to do the work.

Keep in mind that this isn't EVE. Thrust =/= speed in the real world. Thrust is acceleration. That means this device, while not providing very much thrust, provides it for 'free' which would allow very long slow speed ups. It doesn't sound significant, but with the distances involved in space, it becomes rather awesome.
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orange

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #35 on: 17 Aug 2014, 00:05 »

Quote
91 micronewtons of thrust for 17 watts of power, compared to the 40 micronewtons of thrust from 28 watts for the Cannae drive.

Takes forever to get anywhere.  Small solar sails are as effective in the inner solar system.

People keep chasing "special" technology like there is a holy grail to open up space colonization/development, but keep forgetting that it isn't moving around space that is the problem.  It is getting into space that is the challenge, but even that already has a brute force solution that works.  The cost of space is not tied to the technology.  It is tied to the number of engineers & technicians needed to do the work.

Keep in mind that this isn't EVE. Thrust =/= speed in the real world. Thrust is acceleration. That means this device, while not providing very much thrust, provides it for 'free' which would allow very long slow speed ups. It doesn't sound significant, but with the distances involved in space, it becomes rather awesome.

No, it is not Eve.  And I am incredibly frustrated that you think that is what I said.

Thrust is not acceleration.  Thrust is a force, which when applied to a mass creates an acceleration.

Solar sails and ion drives provide very low thrust, but have incredibly high Isp (infinite and ~8000 Isp respectively), how rocket efficiency is measured.  They still take forever to get places - 1 year might become 6-8 months, but it still takes time.

Orbital mechanics gets more complicated with constant thrusting versus the relative impulse thrust provided by a low-efficiency, high-thrust chemical rocket.    Don't get me wrong - low thrust drives let us do really cool stuff.  Constant-burning to from Earth Orbit to Mars Orbit changes a lot with constant thrust; it can shorten the trip.

But even if this quantum-effect drive works and becomes the perfect drive for interplanetary and interstellar travel, it is meaningless if we do not solve the problem of climbing out the gravity well, Thrust-to-Weight greater than 1 is required.

It still does not break the economic hurdle of getting it into space - 1 kg in LEO of anything costs at least $4,600 today.  That cost is not derived from the cost of the materials that go into the rockets (<$5M), it is the thousands of technicians and engineers that design, build, and launch the rocket.
« Last Edit: 17 Aug 2014, 10:51 by orange »
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Saede Riordan

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #36 on: 17 Aug 2014, 00:11 »

Well actually Sawyer, the original creator of the EmDrive, has calculated that if superconducting materials were used to make the drive, it could produce enough thrust to push out of the gravity well.
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Victoria Stecker

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #37 on: 20 Aug 2014, 13:04 »

Huh, I remember seeing something about this at the time that said that the initial nasa report was not a "Hey, look what we did!" but rather a "Hey, can someone figure out what we did?"

It wasn't presented as a reviewed paper, but rather as a sort of request for people to look it over. Reason being, they measured thrust when they turned it on... and also measured thrust when it wasn't supposed to be producing any. If you're not supposed to be producing thrust, and measuring it anyways, that doesn't lend a lot of credence to it when you then measure thrust when you should be.

... haven't really been following this since then.
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Nicoletta Mithra

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Re: NASA confirms - new engine has apparently broken physics.
« Reply #38 on: 20 Aug 2014, 16:30 »

Quote
2. Thrust was also measured from the 'Null Drive', doesn't that mean the experiment failed?

Lots of commenters jumped on this, assuming incorrectly that this was a control test and that thrust was measured when there was no drive.

In fact, the 'Null Drive' was a modified version of the Cannae Drive, a flying-saucer-shaped device with slots engraved in one face only. The underlying theory is that the slots create a force imbalance in resonating microwaves; the 'Null Drive' was unslotted, but still produced thrust when filled with microwaves. This may challenge the theory -- it is probably no coincidence that Cannae inventor Guido Fetta is patenting a new version which works differently -- but not the results.

The true 'null test' was when a load was used with no resonant cavity, and as expected this produced no thrust:

"Finally, a 50 ohm RF resistive load was used in place of the test article to verify no significant systemic effects that would cause apparent or real torsion pendulum displacements. The RF load was energised twice at an amplifier output power of approximately 28 watts and no significant pendulum arm displacements were observed."

Equally significantly, reversing the orientation of the drive reversed the thrust.
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