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Miscellaneous wonders: The Carbon Nanotube Earth Veil

  1. Jan 15, 2016 #1
    Okay so to start, this is just about the most random inapplicable proposal ever, so bear with me. Its just a cool question to consider. So, here goes: What would happen, (again, this is highly theoretical) in the instance that an enormous screen - much like the ones that rests behind most peoples windows - constructed out of carbon nanotubes, for durability, that was somehow (basically impossible) fixed to encompass the entire planet about the cusp of the stratosphere, was just held up by its self? Like as in, what other option does it have other than to just support its self in the sky??? (excluding the possibility of its collapse upon its self, hence the carbon nanotubes) Trying to visualize this can be pretty titilating, as you soon realize that (assuming the construct cannot crumple) it would brace its self together with its own force, as a result of the entirety of the planet's gravity pulling on it from ALL sides with ALL equal force. Correct me if im wrong, but due to the properties of a sphere (globe), this construct WOULD NOT be allowed to descend any further towards the earth (past the stratosphere into the tropopause) because its resting position would be a greater surface area than anything below it, and if it cant contract or crumple... Starting to grasp the implications here? Not sure if it would be possible, but assuming it was, I dont think anything else could happen except for it to stay in the air, seemingly defying gravity its self, thousands of feet above every humans head.
  2. jcsd
  3. Jan 15, 2016 #2
    Post it on Kickstarter. That's my advice. Take it or leave it.
  4. Jan 15, 2016 #3
    Right? Haha. I cant see how it would serve a purpose, but man... this idea is such a mind f*ck. Doesn't seem right, but it has to be.
  5. Jan 15, 2016 #4


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    Staff: Mentor

    You're speculating that it could be rigid enough to support itself? Unlikely, but let's set that aside for now: what would be the point?
  6. Jan 16, 2016 #5
    Well, no real point really. Other than a thought experiment in which an object/construct would "defy gravity" if somehow managed to be set up in an impossibly specific way; one which would result in the planet enacting an equal distribution of gravitational force and thus counter balancing the immense weight of this 'screen'.
  7. Jan 16, 2016 #6
    For what it's worth, Tesla had a similar idea, but his involved a ring around the earth rather than a sphere. He thought that a ring might be built going completely around the earth, say, at the equator, elevated just a meter off the surface by struts until it was complete. Once it was finished, the struts could be knocked away, and the ring would remain suspended. IIRC, he went on to propose the ring could then be made to rotate by some large engine, and people all around the equator could take power off it to run smaller things.

    He didn't think this was practical, he just offered it as an example of the kind of problem he was always thinking about. The story is in his book, My Inventions.
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