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Walking on a cube-shaped planet

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Re: Walking on a cube-shaped planet

#31

Post by jackpirate »

patrickyeon wrote: post #24
aristidb wrote: post #7

"Ask a Physician" has something to say about this: http://www.askamathematician.com/?p=6657

[There should be a standard disclaimer for "I'm correcting you because I think you would benefit from knowing, not because I mean to be an ass"] A physician is a medical doctor. A physicist studies fundamental laws of our universe.

[There should be a standard disclaimer for "I'm correcting you because I think you would benefit from knowing, not because I mean to be an ass"]

I think it would quickly lose it's tone of respect, and take on one of sarcasm.

Re: Walking on a cube-shaped planet

#32

Post by arethuza »

thesz wrote: post #6

Reminded me of Cyberiad: http://en.wikipedia.org/wiki/The_Cyberiad "The Highest Possible Level of Development civilization. A gravely injured hermit comes to Trurl's house and tells Trurl of Klapaucius's adventure: Klapaucius wanders across an old robot, who tells him that he has logically deduced the existence of a civilization that reached the highest possible level of development (hence "HPLD"). He has inferred th…

Highest Possible Level of Development sounds like a Culture ship name and a cubical planet something a Culture ship might do as a practical joke.

Re: Walking on a cube-shaped planet

#33

Post by teeray »

"Earth-scale gravity is so strong that a cube made of the strongest rock would soon be deformed into a ball."

Not necessarily true. If the cube-shaped world has a cube-shaped moon orbiting at the same period as our moon, it will be sooner transformed into a ball by creepers.

Re: Walking on a cube-shaped planet

#34

Post by muyyatin »

CWuestefeld wrote: post #3
blahedo wrote: post #2

The seas wouldn't even be flat to the "surface" of the cube, right? They'd deform into a spheroid. So looking at it from a peak (or from space) it would appear to be a liquid sphere intersected with a solid cube.

Interesting point, but I'm not so sure. We take the shortcut of assuming that the earth's gravity is drawing everything toward a point at the center of the earth. But that's not really correct; every bit of matter is drawing everything else toward it. So those giant mountains that comprise the vertexes of the cube would be pulling the oceans toward them. That works against your point. I don't know where the equilibri…

Sorry I don't have a reference, but as long as you are outside of an object, its gravitational force on you is the same as if it were a point-mass (at least for classical physics).

Re: Walking on a cube-shaped planet

#35

Post by defdac »

If no sci-fi-3d-renderer makes a complete physically based rendering of this I will be surprised. Some nice Mie-scattering-atmosphere simulation with awesome distances and displacements maps from a Borg cube.. Yumm..

Re: Walking on a cube-shaped planet

#36

Post by arctangent »

arethuza wrote: post #32
thesz wrote: post #6

Reminded me of Cyberiad: http://en.wikipedia.org/wiki/The_Cyberiad "The Highest Possible Level of Development civilization. A gravely injured hermit comes to Trurl's house and tells Trurl of Klapaucius's adventure: Klapaucius wanders across an old robot, who tells him that he has logically deduced the existence of a civilization that reached the highest possible level of development (hence "HPLD"). He has inferred th…

Highest Possible Level of Development sounds like a Culture ship name and a cubical planet something a Culture ship might do as a practical joke.

"Minimum Viable Product" would also make for a great Culture ship name :-)

You probably know about this already but for the benefit of others I will post this:

http://en.wikipedia.org/wiki/List_of_ships_of_the_Culture_se...

Re: Walking on a cube-shaped planet

#37

Post by defdac »

defdac wrote: post #35

If no sci-fi-3d-renderer makes a complete physically based rendering of this I will be surprised. Some nice Mie-scattering-atmosphere simulation with awesome distances and displacements maps from a Borg cube.. Yumm..

Ahh.. Here you have a guy that probably can do it in realtime: http://www.youtube.com/watch?v=ehmvVAoSf8M

Re: Walking on a cube-shaped planet

#39

Post by xsmasher »

muyyatin wrote: post #34
CWuestefeld wrote: post #3

Earlier quoted context omitted.

Interesting point, but I'm not so sure. We take the shortcut of assuming that the earth's gravity is drawing everything toward a point at the center of the earth. But that's not really correct; every bit of matter is drawing everything else toward it. So those giant mountains that comprise the vertexes of the cube would be pulling the oceans toward them. That works against your point. I don't know where the equilibri…

Sorry I don't have a reference, but as long as you are outside of an object, its gravitational force on you is the same as if it were a point-mass (at least for classical physics).

Which points to the oceans "bunching up," not laying flat.
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