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Can Earth sustain much bigger object with an infinite weight?

  1. Mar 24, 2012 #1
    I know this question maybe a bit funny, others will call this post BS. But just assume if any object, having a size that ten times larger than Earth and having infinite weight, can the Earth resist such pressure? I recalled somewhere mentioned that Earth, theoretically, can support weight without limits.
     
  2. jcsd
  3. Mar 24, 2012 #2
    To have infinite weight you'd need infinite mass. There is no such thing. If an object has enough mass in a small enough space (high enough density) the gravitational force will overtake the nuclear force, and you'd have a black hole, including the Earth.
     
  4. Mar 24, 2012 #3
    Just assume that there are very large object, for example a filament hundred times more larger and massive than earth, which have infinite weight going to wrap the Earth, what would happen? Can the Earth resist it? Because I heard Earth can support infinite weight.
     
    Last edited: Mar 24, 2012
  5. Mar 24, 2012 #4
    Like the previous poster said, if it has infinite weight then it would have infinite mass and thus would collapse into a black hole, so no the earth cannot support infinite weight.
     
  6. Mar 24, 2012 #5
    Okay, now if a giant object, for example a single filament which is million times larger and heavier than Earth, going to wrap around Earth with full pressure, can the Earth sustain it? Note the giant filament don't have infinite size and weight, but having size and weight million times than Earth.
     
  7. Mar 24, 2012 #6
    Such a dense filament would cut through the Earth and come to rest at the center.
     
  8. Mar 24, 2012 #7

    Ryan_m_b

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    You heard wrong. If a suitably dense mass was placed on the Earth's surface it could sing through the ground, the crust, into the mantle and all the way to the core.
     
  9. Mar 24, 2012 #8
    If the filament diameter is smaller than Earth, then it will cut through the Earth. But a filament with a diameter million times the Earth size, plus weight million times heavier than Earth weight, are you sure it will crush Earth? I'm still thinking that Earth will resist it.
     
  10. Mar 24, 2012 #9
    What I think is that, From the laws of gravitation, as long as the earth has same angular velocity, it would stay at the same orbit, [compare the earth's centripetal force and sun's gravitational force], since the angular momentum should be conserved, adding the infinity mass to the earth, the angular velocity of the earth will change approaching zero... so as a result the earth would have to move very far away from the sun.... How's that guys...??
     
  11. Mar 24, 2012 #10

    tony873004

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    What would happen to you if you placed something millions of times more massive and larger than you, on you? How about something 1023 times more massive than you? You're actually doing this right now! You are on the Earth, but you could also look at it as if the Earth were on you. So, yes, you could sustain this.

    Earth might not do as well. You and Earth hold your shapes for very different reasons. Placing Earth on a much more massive and larger object would be like placing a spherical raindrop on Earth. Upon contact it spreads out into a thin layer. Earth would likely do the same. It would become like a thin layer of paint on the surface of the massive object.
     
  12. Mar 24, 2012 #11
    Hmm, you will reach infinite weight and mass if you are accelerating at the speed of light. But, black hole can sucks everything, that can generate a gravitational field that so strong even light can't escape from it because of the acceleration at the singularity. So, does it mean that black hole gravitational field ,tidal force and the acceleration at singularity are beyond infinity? Because even light can get sucks by this force.
     
    Last edited: Mar 24, 2012
  13. Mar 24, 2012 #12
    Physics to our understanding forbids massive objects from accelerating at the speed of light.


    Yes anything that goes too close to a black hole without sufficient momentum or acceleration in a direction that will cause it to not collide will fall into it. Yes light cannot escape from a black hole. If you are suggesting black holes have the gravitational well they do because they are accelerating at the speed of light that is not correct. Also singularities are not believed to be real physical objects.


    What? I understand that your previous understanding and chain of logic is flawed but what part of your earlier logic leads you to conclude that 'black hole singularities have acceleration that exceed infinite due to light not being able to escape it' :S Remember that the speed of light is finite...
     
  14. Mar 25, 2012 #13

    If the the diameter is a million times that of Earth and the weight is also a million times Earth then the density less than one millionth of that of the density of Earth. Such a filament would not even be noticeable.

    What if the Earth were in the center of a huge planet a million times the diameter of Earth with a density at the surface the same as Earth? That would be much larger than the Sun.
    I think the immense pressure would collapse the center into a black hole immediately.
     
  15. Mar 25, 2012 #14
    Not really. The size and mass of the other object doesn't necessarily matter. What is important is the gravity at the surface of the other object. A minimum size black hole is only a few kilometers across ( I think ) but the Earth would be complete destroyed by it. A larger object with the same mass would be less dangerous. At the other extreme a gas cloud of the same mass as the black hole would have no effect at all.

    What about placing the Earth on the surface of Jupiter? I think the Earth would crush into a hemispherical shape.
     
  16. Mar 25, 2012 #15
    Those black hole thing's starting to fascinate me. What force in the universe that can destroy a black hole, even able to annihilate supermassive black holes?
     
  17. Mar 26, 2012 #16

    Chronos

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    There is nothing special about a black hole - until you approach the event horizon.
     
  18. Mar 26, 2012 #17
    Unless there is a physics definition for the word destroy I am not aware of:
    1.
    to reduce (an object) to useless fragments, a useless form, or remains, as by rending, burning, or dissolving; injure beyond repair or renewal; demolish; ruin; annihilate.
    2.
    to put an end to; extinguish.
    3.
    to kill; slay.
    4.
    to render ineffective or useless; nullify; neutralize; invalidate.
    5.
    to defeat completely.

    Definition 3 is not applicable unless black holes really are 'monsters' and are conscious beings I suppose. :P

    Definition 4 there is not one answer for, your question would need to be more specific as to what context you mean.

    Definition 5 I'd change defeat to eliminate from existence.

    The answer is Hawking Radiation. Or, in a less scientific wording the thing that can destroy a black hole is itself.
     
  19. Mar 26, 2012 #18
    On a slightly more "realistic" note, what do you think would happen if you took the moon, and gently rested it on the Earth? Imagine neither are rotating and there is no sun, so the only force to worry about it their mutual gravitational pull. Are they massive enough to ensure mutual destruction and reformation into a larger planet? Or could they sustain some sort of potato shape?

    I suppose they will destroy each other, since there do not seem to be potato shaped objects of the size of the Earth. But then maybe that is largely due to angular momentum considerations during formation?
     
  20. Mar 26, 2012 #19
    It is believed that the Earth captured the Moon in a collision. Both bodies melted. The Moon was scattered as a ring of blobs of various sizes that later coalesced.

    A molten Moon. It must have been bright as the Sun. The current moon is as black as coal, it only seems to be reflective.
     
  21. Mar 30, 2012 #20
    Interesting to say the least.
    If I may indulge? and if I understand your post... If one, anyone could sustain their weight while dispursing/spreading it over a larger suface area relative to the Earth. That person would move away from the Earths surface at any point on the globe? I'm abiously not a learned person in this regard. never the less indulge me.
     
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