Walking on a cube-shaped planet
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Walking on a cube-shaped planet
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Re: Walking on a cube-shaped planet
#2The 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.
Re: Walking on a cube-shaped planet
#3The 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 equilibrium between those forces sits, nor do I know how to calculate it.
Re: Walking on a cube-shaped planet
#4The 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…
A sphere with some gravitational influence from the points, but with most of the mass towards the center of the cube, it would still be mostly sphere-like, I think.
Re: Walking on a cube-shaped planet
#5I imagine walking on a cube-shaped planet will be not different that doing it on a sphere shaped one.
Re: Walking on a cube-shaped planet
#6Reminded 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 the existence of such a civilization by figuring that if there are different stages of development, there will be one that is the highest. He was then faced with a problem of identifying that one; as he noted, everyone claimed that theirs was the HPLD. Upon much research and thought, he decided that the only way to find it is by looking for a "wonder", i.e. something that has no rational explanation. Eventually Klapaucius discovers one such wonder: a star in the shape of a cube, orbited by a planet also shaped like a cube with the huge letters HPLD written on it."
Now I know how it is like, to be one of HPLD.
Re: Walking on a cube-shaped planet
#7"Ask a Physician" has something to say about this: http://www.askamathematician.com/?p=6657
Re: Walking on a cube-shaped planet
#8The 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…
One place to start would be the Schiehallion Experiment of 1774 where a symmetric and isolated mountain in Scotland was used as the basis of an experiment to measure how much the gravitational attraction of the mountain pulled a pendulum away from the vertical. The goal being to estimate the mass of the Earth - with what turns out to have been a reasonably accurate result.
During the course of the experiment they had to measure the shape of the mountain quite carefully and they had the idea to join points of similar height together with a line on the map - inventing contour lines.
Re: Walking on a cube-shaped planet
#9> On spherical earth the horizon on average is a little over three miles away.
I read (long time ago) that the horizon is 29km on a seashore. In other words if you see a ship disappear on a horizon, it was 29km away. And so his 3mi vs my 29km is a bit of a discrepancy. Can anyone set things straight here?
Re: Walking on a cube-shaped planet
#10Regarding the perceived gravity on a cube planet, the movie Sunshine tries to portray accurate physics for a similar situation. It has great sci-fi visuals, though the end gets a bit... silly.