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Thread: A really out there black hole theory.

  1. #1 A really out there black hole theory. 
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    Okay, If a black whole gets fed enough to where the little piece of matter inside it grew to the size it was when it became a black hole would it then shrink again? or could it shrink again? And if it did is there anyway to tell what would happen?


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    nobody knows, we didn't even ever seen a black hole once, we have scanned them, they appear to be there. But nothing is sure.

    I doubt that everything that comes in the black hole stays in there. I bet it get's drawn into another dimension or get's scattered.


    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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    I thought black holes were points of infinite density, and so can't change in size. There was also something about how they slow down time to an outside observer, so that any object moving towards the black hole will never appear to pass the event horizon, and yet to the object going towards the black hole times procedes normaly and it will pass the event horizon. I have no idea if any of that is right, but if it is then would that mean that its impossible to add mass to a black hole? If it is impossible, then that sort of invalidates your question.
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    Quote Originally Posted by Zwolver
    I doubt that everything that comes in the black hole stays in there. I bet it get's drawn into another dimension or get's scattered.
    the only reason they never come out is because the escape velocity of the black hole is higher than the speed of light. that is also why if light goes in, it cant go back out. thats why they are called black holes.
    I don't suffer from insanity, i enjoy every minute of it

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    Quote Originally Posted by bubbleclip
    I thought black holes were points of infinite density, and so can't change in size.
    the mass can increase as you put more things in the black hole. black holes acually get smaller in volume as they increase in mass, because the gravity pulls so hard that all the mass 1 inch away from the center of the black hole is under intense preassure, and the density increases as does the mass.
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    Also, if you were close to a black hole, with your legs being the closest part to it, then the attraction would pull your legs more then the rest, you would elungate.
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    Quote Originally Posted by oracle
    Also, if you were close to a black hole, with your legs being the closest part to it, then the attraction would pull your legs more then the rest, you would elungate.
    or indeed, your toes.
    I don't suffer from insanity, i enjoy every minute of it

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    If you feed mass into a black hole the event horizon (the distance from the black hole's center from which light cannot escape) will grow larger. The mass of the black hole will increase. The density of the black hole will stay close to infinity since the volume of the matter in its center will still be close to zero.
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    it would take energy to do that, but if the black hole sucks up to much matter, won't it drain itself?
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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    Bubbleclip, you have it reversed. Time slows for the particle being absorbed (for lack of a better word). Time for observers is unchanged, which is why we can detect the radio waves emitted by the intake of matter.

    it would take energy to do that, but if the black hole sucks up to much matter, won't it drain itself?
    Zwolver, why doesn't the gravity of the Earth drain itself? Gravity is what powers a black hole.
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    How much gravity do you need to stop light from escaping ?
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    Quote Originally Posted by oracle
    How much gravity do you need to stop light from escaping ?
    I think you mean how much MASS do you need to stop light from escaping, and the answer is that literally any amount will do. If you have a computer and squeeze it to the point where it is probably less than 1 micro meter in radius it could keep some light that traveled right next to it from escaping. Now that would be a pretty crummy black hole but a black hole none the less
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    Well, i am studying black holes and general relativity atm, so lets see if i can shed some light onto this.

    A black hole is any object whose entire mass is located at some single point called the singularity. Any mass falling into the black hole will be compressed into the singularity, keeping all of the mass at the singularity. Surrounding the black hole is a sphere at which the escape velocity for any object is the speed of light, c. This sphere is called the event horizen, and any object that passes beyond this sphere can never return to the outside world in its original form (all world lines within the event horizen converge to the singularity, so it is not possible to escape).

    If one applies quantum field theory to the surrounding area of the event horizen, then one finds that virtual pairs of photons and antiphotons are constantly being created and annihilated. occasionaly the antiphoton will fall into the black hole and the photon will escape the black hole in the form of thermal radiation, called hawking radiation. This will always be happening to the black hole, so all matter that falls into the black hole must eventualy come back out in the form of thermal radiation. This means that all black holes will eventually evaporate into massive amounts of thermal radiation. The total energy of this thermal radiation is simply equal to the mass of the original black hole times the speed of light squared. An interesting thing to note is that smaller black holes have more spacetime stress at the event horizen than more massive black holes, so a smaller black hole will produce more virtual pairs of photons and antiphotons, and will thus produce more radiation.

    Now, onto what happens as one falls into a black hole. General relativity predicts that as an observer approaches the center of a gravity well, in this case a black hole, time will slow down. This means that as you fall into the black hole, time slows down around you, which means you will actually be intact from your perspective than one would expect, but you will still make it to the singularity in a finite amount of time. Another interesting thing to note is that the world line with the maximum proper time is an unaccelerated one. This means that if you try to escape the black hole via rocket engines or some similar mechanism, you will only fall into the singularity faster.

    Now, what does it look like to an outside observer looking at you ass you fall into a black hole? He sees you approach the black hole as normal until you begin to approach the event horizen. The proximity to the gravity well means that time will slow down for the observer. this means that the outside observer will see the person get closer and closer to the event horiven, but never actually see him enter.

    Finally, is it even possible to make it to the event horizen? The answer depends on the size of the black hole. The difference in gravitational force between your feet and your head will cause you to stretch out, or spaghettify. This force is called the tidal force. In smaller black holes, the tidal force extends far beyond the event horizen, so you will be ripped to shreds before you even make it close to the black hole. In supermassive black holes, the event horizen extends far beyond the event horizen, so you will pass through the event horizen without noticing a thing.
    I demand that my name may or may not be vroomfondel!
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  15. #14  
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    I'll never listen to Muse - Super massive black hole the same again.

    Still, how do they exist, do they begin as a small black hole, or as a huge?
    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
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  16. #15  
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    Im pretty sure that the current theory is that they started out as thousands of massive stars at the center of each galaxy, and something like the energy lost from gravitational radiation caused them to collapse into a suppermassive black hole.
    I demand that my name may or may not be vroomfondel!
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