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If the Earth were a cube.

  1. Apr 23, 2013 #1
    Hypothetically, if the Earth were a cube, would walking to the corners(vertices etc.) feel like you were going uphill or would it feel flat?
     
  2. jcsd
  3. Apr 23, 2013 #2

    Danger

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    I don't know, but it's a sure bet that I'd trip and fall off of the edge... :rolleyes:
     
  4. Apr 23, 2013 #3

    Drakkith

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    I'd guess it would feel like uphill.
     
  5. Apr 23, 2013 #4

    Evo

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    Both ways? :tongue:
     
  6. Apr 23, 2013 #5

    collinsmark

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    Yes, uphill (on your way toward a corner/edge, and assuming you are already closer to that corner/edge than the corner/edge behind you.) Your idea of what "down" is (and feels like) would always be pointed toward the center of the huge cube.

    [Edit: Evo: :biggrin:]
     
  7. Apr 23, 2013 #6

    Drakkith

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    Nonsense. Once you step over the edge you just slide down the rest of the way!
     
  8. Apr 23, 2013 #7

    Evo

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    :tongue:
     
  9. Apr 23, 2013 #8

    SteamKing

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    If the earth were a cube, everybody would be like square, man.
     
  10. Apr 23, 2013 #9

    Danger

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    Oh, please, no! We'd still be up to our asses in Beatniks. :bugeye:
     
  11. Apr 23, 2013 #10

    Drakkith

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    I'm far too hip to be square.
     
  12. Apr 23, 2013 #11
    Don't worry about being square, it's the new circular.

    Yes, that's the best I've got.
     
  13. Apr 23, 2013 #12
    The surfaces would always look flat but feel increasingly tilted as you walked toward a corner or an edge.
     
    Last edited: Apr 23, 2013
  14. Apr 23, 2013 #13
    Good question! Now I'm going to be asking everyone I know this question.
     
  15. Apr 24, 2013 #14

    Danger

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    I've seen your hips; you're more pear-shaped than square.

    My condolences.

    And you've been a devotee of Dale Carnegie for how long?
     
  16. Apr 24, 2013 #15

    chiro

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    Last edited by a moderator: Sep 25, 2014
  17. Apr 24, 2013 #16

    Garth

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    7857919092_36751e55ba_o.jpg

    I've always known "It's a Square World"!!

    It's a Square World

    A zany TV comedy programme that had me in stitches whilst a teenager; ah those were the days my friend......

    Garth
     
  18. Apr 24, 2013 #17

    FlexGunship

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    I'm most interested in the idea of a vertex of ocean. The question leads a lot of the topographical details to the imagination, but I'm fairly confident that, of any eight equidistant Terran-verticies, at least one would be in water.

    "We'll take the boat to the top of Ocean Peak, and we'll water ski down!"
     
  19. Apr 24, 2013 #18
    That would also bring up the matter of "What is 'sea-level'"
     
  20. Apr 24, 2013 #19
    Which way are the gravity vectors pointing at the vertices? It seems the vertices are like giant mountains which might support glaciers if the atmosphere could extend that "high", but liquid water would run off toward the center of each face.
     
    Last edited: Apr 25, 2013
  21. Apr 26, 2013 #20
    That's a good question. On earth, the gravity vectors are everywhere perpendicular to the ocean surface, as you would expect. The only places where the gravity vectors on a cubic planet are perpendicular to the cube surface are at the center of each face. So any surface water is constantly trying to get to that point, creating a lot of turbulence. If surface water behaves as it does on earth, the gravity vectors are always perpendicular to the mean water surface. So what would the ocean surface look like? It would not be "flat"; that is, conforming to the surface of the cube face.
     
    Last edited: Apr 26, 2013
  22. Apr 26, 2013 #21
    Also, what would it [the planet's actual surface, mind you] look like to the people inhabiting it? As far as we're concerned, because we're so small compared to the earth, and so close to its surface, everything looks flat to us. In the case of a planet (or any celestial body, really) actually being flat (topography notwithstanding), the gravity would likely be biased toward the center of each face, but would it also look as if everything is tilted very slightly upward from the perspective of a person standing at the center of one of the faces (Probably not)?



    EDIT: And what would seasonal changes bring about, or even be like?
     
    Last edited by a moderator: Apr 26, 2013
  23. Apr 26, 2013 #22
    Would it? Turbulence implies conversion of energy. So you would expect an energy source or it would look like a perpetume mobile.

    That would be a challenge to calculate. Incidently on a much smaller scale but the same principle, the effect on gravity of ice sheets melting after the last ice age is well understood, see this. Sea levels are slightly modified as the gravity anomaly of the melted ice sheets have their (minute) effect on the direction of the gravity vector. I believe Nils Axel Mörner is credited for that but I can't find the applicable ref right now. Maybe this.
     
    Last edited: Apr 26, 2013
  24. Apr 26, 2013 #23

    collinsmark

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    Yes, if an ocean of water was added to this cube the water would pool at the particular face in sort of upside down saucer sort of shape. And, (assuming that the weather is calm at the time) the gravitational acceleration vector would still be perpendicular to the surface of the water, just as it is here.

    If you were at the center of one of the faces, and assuming you are not under water (we'll say the face in question does not have an ocean), the horizons would stretch out very far. The the land would still look as flat as can be. The land itself would not appear to be tilted at all.

    But if you were to take out your telescope and look at people and buildings closer to the edges you would notice that they seem to be tilted: they would all seem to leaning away from you.
     
  25. Apr 26, 2013 #24

    nsaspook

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    I'm sure some of you remember the old comic book series:
    http://asitecalledfred.com/comics101/images/2003/sep24/bizarroworld.jpg [Broken]
     
    Last edited by a moderator: May 6, 2017
  26. Apr 26, 2013 #25

    BobG

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    I would not like a cubical Earth where there were no spherical cows.

    And spherical cows could not exist on a cubical Earth, since they'd all roll downhill into the water.
     
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