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Thread: Is the EM Drive a warp bubble drive?

  1. #1
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    Is the EM Drive a warp bubble drive?

    Looks like it works in a vacuum. Now for the peer reviewed studies.

    http://www.escapistmagazine.com/news...ks-In-A-Vacuum

    This is really exciting. I didn't even think it was possible to build a warp drive. Never imagined it might happen in my lifetime.

    Do you think this is for real?

  2. #2
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    Hmm, this would be the same experimental set-up that reported positive results not just for the EMDrive but for what was effectively just a tin can?

    I'm holding off on excitement until it is shown to work for a number of experimental configurations. It sounds too much like a effect unrelated to the actual drive is being measured.

  3. #3
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    http://www.wptv.com/mobile-showcase/...tellar-travel_

    Found another new article. Fingers crossed!

  4. #4
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    All of these articles are referencing the same report. Which is on NASASpaceflight.com (which is not a NASA site, it was just set up by some people who worked there at one point and is a purely commercial site). If you follow it back this is based on work by March et al, a group of five or so who did the original 2013 testing which I mention above. This was presented at a conference and I cannot find a journal article about it. Or the latest results. My google-fu may be weak - can you provide a peer reviewed journal reference for this work? Media reference like those that you are currently citing are just press pieces based on a report that is in turn based on a spaceflight.nasa.gov post as far as I can see.

  5. #5
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    It's the same setup they were testing in a vacuum chamber at ambient pressure. They finally found some electronics that could withstand vacuum, but did nothing to fix all the other problems with their apparatus. Just enclosing the device in an airtight container would have largely removed the need for a vacuum chamber (and would have allowed using equipment that couldn't function in vacuum), and evacuating the chamber doesn't eliminate the possibility of outgassing or charged particle emission causing problems. They're still pretending they can supply power through fancy liquid metal contacts without possibly applying torque, which is wrong, they need to put batteries in the same container as the drive, moving with it. There are other fundamental issues with their measurement, such as sensitivity of the torsion balance to shifts in center of gravity due to it not being vertical.

    Their measurements are meaningless garbage due to the many flaws in their measurement methods (flaws which they refuse to acknowledge or fix, even when doing so would be simpler and cheaper than their chosen methods), so there is no evidence to support their claims of thrust. Their theory itself is nothing but technobabble, and their claimed behavior violates such thoroughly tested things as the conservation of energy and momentum and not only requires a preferred rest frame, it requires that Earth's surface be at rest in that frame.

  6. #6
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    NASA does have a lot of people who are quite used to dealing with measuring forces to high levels of precision (and accuracy), but I suspect this group is not being careful enough.

    Fleischman & Pons, whose results were more problematic from Day 1*, had people scrambling to replicate, all of whom failed. This EM thruster experiment does not sound like one that would require a well-equipped physics laboratory to buy millions in equipment to replicate (or not). Indeed, I suspect that a well-equipped college physics or engineering lab could reproduce (not necessarily duplicate) the experimental setup without buying much of anything. Make it a class project -- if nothing else, it would be very good practice in setting up high-precision experiments.


    -------------------------

    * No neutrons. No gamma rays. No apparatus to detect either, perhaps.

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  7. #7
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    They're talking about forces of several tens of micronewtons, even with just watts of power...about a micronewton per watt. The Cavendish experiment measured a force of 0.174 micronewtons over two centuries ago, and indeed, is frequently repeated by students. They really have no excuse for such sloppy work.

  8. #8
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    I saw an "article" about the EM Drive and how it won't save astronauts from cancer on a trip to Mars. In reading further than the title, the whole article was not about the EM Drive or cancer. It was about mice being subjected to radiation and the side effect of that was poor cognation. The last couple of paragraphs were about how the radiation used in the experiment was nothing like the threat faced by Mars bound astronauts.

    At the end, I did a head tilt trying to figure out what I just read and why. I'd link to the "article", but that might be cruel.
    Solfe

  9. #9
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    Quote Originally Posted by Solfe View Post
    At the end, I did a head tilt trying to figure out what I just read and why.
    It might help to have your cat read the article. They're really good at that head tilt thing. You have a cat?

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  11. #11
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    Whoops, Squink - looks like one crank supporting a crank-like idea!
    Dr Mike McCulloch is a Lecturer in Geomatics at the School of Marine Science and Engineering Plymouth University - Plymouth, PL4 8AA, UK.
    McCulloch has several letters at Europhysics Letters about this inertia is due to Unruh radiation idea over the last years.
    An obvious flaw - inertial mass does not depend on the area that is exposed to any radiation pressure. 1 kilogram of lead has the same inertial mass whether it is a sphere, cube or a plate!

    The word crank comes to mind when
    • you read a letter with 4 out of the 10 references to the author, 4 to conferences and 1 to New Scientist
    • an author has been touting an idea for at least 9 years and cannot cite anyone supporting his idea.

  12. #12
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    Some talk here
    http://forum.nasaspaceflight.com/ind...pic=39772.1760

    EM--if it worked--would be more of an impulse drive--not Sonny White's warp.

  13. #13
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    Looks like this is the latest em drive thread.

    German Test Reveals That Magnetic Fields Are Pushing the EM Drive
    "Researchers in Germany have performed an independent, controlled test of the infamous EM Drive with an unprecedented level of precision," writes PvtVoid. "The result? The thrust is coming from interactions with the Earth's magnetic field."

  14. #14
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    It's usually a good idea to provide a link to the research paper. Popularized summaries often are too inaccurate.


    Here's a link to the abstract of the original paper:

    https://www.researchgate.net/publica...fect_Thrusters

    Here we are reporting first results of our improved thrust balance as well as EMDrive and Mach-Effect thruster models. Special attention is given to the investigation and identification of error sources that cause false thrust signals. Our results show that the magnetic interaction from not sufficiently shielded cables or thrusters are a major factor that needs to be taken into account for proper µN thrust measurements for these type of devices.
    A copy of the original paper is available at
    https://www.researchgate.net/profile...ication_detail

    The SpaceDrive Project – First Results on EMDrive and Mach-Effect Thrusters
    BARCELO RENACIMIENTO HOTEL, SEVILLE, SPAIN / 14 – 18 MAY 2018
    Martin Tajmar, et al.
    Last edited by selden; 2018-May-22 at 07:03 PM. Reason: added paper's title
    Selden

  15. #15
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    Looks like I skipped the link entirely. My error.
    Thanks, Seldon.

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