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I have read this question:

Is the force of gravity always directed towards the center of mass?

And G. Smith's answer lists a site where they specifically talk about this case mathematically.

https://possiblywrong.wordpress.com/2011/09/09/if-the-earth-were-a-cube/

At the center of each cube face, the force of gravity is almost exactly 1 g; at each corner, however, it is just 0.646 g, meaning that a person weighing 200 lbs. here on Earth would weigh only 129 lbs. A slightly weirder effect is that, standing on the flat surface of a cube-shaped planet, the force of gravity is not always “down.” That is, as you walk in a straight line from the center of a face toward a corner, gravity causes the flat face of the cube to seem to get steeper and steeper, so that you are eventually climbing instead of walking.

enter image description here

https://gizmodo.com/how-gravity-would-be-different-if-the-world-were-a-cube-1492018223

And this is very strange feeling you are like on the moon, much lighter, you could jump really high (but not fly away contrary to popular belief), and in some parts of the cube surface, and walking from the center to the corner you feel like climbing, meaning I believe that you could feel like rolling back to the center.

On Earth, an average jump can go 0.5 metre high, for 1 second. On the Moon, it is 3 metres and 4 seconds.

https://www.sciencealert.com/here-s-how-high-you-could-jump-on-other-worlds-in-the-solar-system

Question:

  1. How high can you jump (at the corner) on Cube-Earth (and are the corners really like steep hills)?
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    $\begingroup$ The Wordpress blog post you linked describes the gravitational field at the surface of a cubic Earth, including its direction, with diagrams and all. What do you want to know besides what is described in that post? $\endgroup$
    – Archimaredes
    Commented May 1, 2020 at 18:36
  • $\begingroup$ @Archimaredes is it like on the Moon, can you fly away if you jump too big for example? Can it really be true to be rolling back from the corner like it it was a steep hill? $\endgroup$
    – Árpád Szendrei
    Commented May 1, 2020 at 20:44
  • $\begingroup$ Why the downvote? $\endgroup$
    – Árpád Szendrei
    Commented May 1, 2020 at 20:44
  • $\begingroup$ Yes, gravitationally speaking, the corners are like steep, pointy mountains. $\endgroup$
    – PM 2Ring
    Commented May 1, 2020 at 20:59
  • $\begingroup$ @PM2Ring thank you, I am just guessing maybe there might be areas, like the edges, corners, centers, somewhere where gravity would be weaker so you could jump really high. $\endgroup$
    – Árpád Szendrei
    Commented May 1, 2020 at 21:06

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You can't fly away if you jump too high on the Moon in the first place. The Moon's escape velocity is 2380 m/s.

Besides that, the Moon's surface gravity is only 1/6 that of Earth, or in other words roughly $0.167g$. The minimum gravity on cube Earth is $0.646g$, about four times stronger than the Moon's gravity.

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  • $\begingroup$ Thank you so much! $\endgroup$
    – Árpád Szendrei
    Commented May 1, 2020 at 21:00

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