Cut in half
Posted: 25 August 2012 10:06 AM   [ Ignore ]
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After watching a few very strange video game battles i have a strange question:

Lets say we would be able to cut the planet in half, what would happen?
Would the gravitation keep both parts together, with “minor” catastrophes like lava bursting out, or changes in the sealevel, or would the parts slowly drift away from each other?

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Posted: 25 August 2012 10:25 AM   [ Ignore ]   [ # 1 ]
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The molten core would merge back together as fast as you cut it.

Surface effects would be annoying.

Cut at the equator or pole to pole?

psik

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Posted: 27 August 2012 07:17 AM   [ Ignore ]   [ # 2 ]
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I would have thought the sudden release of internal pressure would fracture the crust to a certain extent, but not to the point it that most of it wouldn’t collapse back together almost immediately.  It probably wouldn’t “explode” the way the movies would have you believe.

This question reminds me of something I saw (probably a Stargate episode) where an asteroid was about to hit Earth.  The only thing they could think to do at the very last minute was rig up some kind of gizmo to shift the asteroid into hyperspace for just a second, just long enough to pass through the Earth without harming it!  And then pop, the asteroid goes on its merry way.  And I thought at the time… that close wouldn’t the Earth’s gravity drag it right back?

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Posted: 27 August 2012 07:34 AM   [ Ignore ]   [ # 3 ]
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I suppose that it depends on the cutting instrument. What kind of object can slice a planet in half? I don’t know.

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Posted: 27 August 2012 11:33 AM   [ Ignore ]   [ # 4 ]
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This whole conversation is silly, but (so?) I’ll add my comments. smile

First, assume some sort of super laser that could zip through the earth.  I would guess that the two halfs would immediately weld themselves back together.  The only problem is that the bond there might be a bit weaker so it could be another earthquake fault.

Second, if the asteroid were in hyperspace, (another universe) temporarily, it’s extremely doubtful that the force of earth’s gravity against it’s speed would be enough to pull it back, probably just slow it down a bit as it went on its way.

Occam

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Posted: 27 August 2012 04:10 PM   [ Ignore ]   [ # 5 ]
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gravity would hold it together.  Interesting question…...

Science Fiction - shows up in one of Gregory Benford’s books

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Posted: 27 August 2012 04:43 PM   [ Ignore ]   [ # 6 ]
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Without a violent impact creating scattering forces, the earth would hold together, though some eruptions of pressurized surface pockets might occur.  In the center it would not even been noticable, like slicing a liquid in half. IMO

[ Edited: 27 August 2012 04:45 PM by Write4U ]
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Posted: 27 August 2012 05:28 PM   [ Ignore ]   [ # 7 ]
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Alexander80,

Before I answer… Are you a super villain looking for a way to black mail the people of Earth?

LOL

Take care,

Derek

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Posted: 28 August 2012 09:53 AM   [ Ignore ]   [ # 8 ]
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Occam. - 27 August 2012 11:33 AM

Second, if the asteroid were in hyperspace, (another universe) temporarily, it’s extremely doubtful that the force of earth’s gravity against it’s speed would be enough to pull it back, probably just slow it down a bit as it went on its way.

Occam

Why not?  Where does it get its speed anyway?  Any object moving in a perfectly straight line is probably not going to hit a planet at random.  But at a certain point, the body is going to be caught in the Earth’s gravity well, correct?  At that point it is being actively pulled toward the Earth, and accelerating because of Earth’s gravity well.  It would seem to me that just shifting it out of phase for a few seconds isn’t going to work.  The asteroid would just spiral back into the Earth again, wouldn’t it?

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Posted: 28 August 2012 10:35 AM   [ Ignore ]   [ # 9 ]
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First, the major external force would be from the sun’s gravity, making the asteroid probably travel in an elipse.  If its path crosses the earth’s orbit or comes very close to it, sooner or later, maybe once in many millions of years, then it can collide with the earth.

However, I’m not very knowledgeable about this.  We’ll have to wait for Darron to check in because he can explain all the facets of this much more clearly and expertly.

Occam

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Posted: 28 August 2012 11:23 AM   [ Ignore ]   [ # 10 ]
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Alexander80,

Before I answer… Are you a super villain looking for a way to black mail the people of Earth?

No i have watched the cutscene compilation of Asuras Wrath, in one of these he is impaled by his former teacher Augus with a Sword that is so long that it goes through the whole Planet (somehow i think that was some sort of sexual innuendo).
He (Asura) also fights Enemies as big as Earth, and the Solar System.
Totaly unbelievable, but funny.

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Posted: 28 August 2012 02:42 PM   [ Ignore ]   [ # 11 ]
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In a way, this is a nonsensical question. Cutting, when we look at the actual forces involved, is breaking electromagnetic bonds of various sorts. Electromagnetism is not the dominant force holding the Earth together, so in a sense it isn’t really possible to ‘cut’ it.

Probably the closest equivalent that I can think of would be having a neutron star or a black hole pass through the Earth - there, at least something is presumably causing damage and going through the Earth, but ‘cutting’ would not really be the correct term.

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Posted: 12 September 2012 09:25 PM   [ Ignore ]   [ # 12 ]
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About the question of wether the asteroid that was forced into hyperspace and then back into normal space would be attracted back to earth, this situation is almost identical to the question about how fast would you have to throw an object straight up from earth to have it never come back, essentially escaping the gravitational pull of the planet earth. This is called, appropiately enough, the “escape velocity” which is about 7 miles per second (if measured at the surface of the earth). So, the answer to the question is: If the initial velocity of the asteroid relative to the earth is less that 7 miles per second, it would indeed fall back into earth. Otherwise, it would not.

Héctor (hpcaban)

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Posted: 12 September 2012 09:41 PM   [ Ignore ]   [ # 13 ]
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I just remembered a situation that is reminiscent of the asteroid being moved into hyperspace and then back into normal space once it has passed beyond earth. Without going into too many details, there is a well known phenomemon in quantum physics called “tunneling” where, for example an electron is separated from a region in space by a “potential barrier” that is a region of space where the electron cannot be because it does not have enough energy. So, you would expect the electron to never appear on the other side, and yet it does. Not only is the probability of it predicted by quantum physics but it can be detected experimentally on the other side as well. As a matter of fact, there is even an electronic device called a “tunnelling diode” which works on this principle (“tunnelling” because it is as if the electron had found a “tunnel” to the other side). So, how does the electron go from A to C without ever existing in the prohibited region B? Could it be that if jumps into another parallel universe when approaching the potential barrier and jumps back into our universe once it has cleared it?

Héctor

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