Shoutbox

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Originally posted by John Anderton

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Originally posted by CookieRevised
They are objects. Only objects with an extremely great mass (and because of that extremely small... they think). Black holes aren't all the same either, some have a greater mass than others.

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O.o
Their mass is the mass of the helium remaining from nuclear combustion !!! The gravitational force comes from their negligible volume and high mass.

They think ??? Who think ?? Do you mean i think

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No, "they" (points finger to wierd scientists)...

Studies suggest black holes can have different masses. aka: it doesn't have  infinite mass at all, and it can be different from the other black hole. Black holes are not so "black", and perhaps not "holes" either. The volume and masses of black holes can't be measured per-se, it is done in theory and calculation, but even that theory (eg: when you reverse the formula of calculating escape velocity near the event horizon) suggests black holes have different masses. Heck, if you say it has infinite mass, many famous important theories wouldn't even work.

As for the size, that's also pure theory and done with calculation based upon current physicis as we know it. Thing is, these current physics don't apply 100% when dealing with such stuff. Also, a black hole is more than simply "the extremely small thing" which sucks everything in; as that is called the singularity in the middle of a black hole. One black hole can have a larger inner and/or outer event horizon than the other, meaning the gravity is different than the other, meaning the mass is smaller/greater. eg: a solar mass black hole has a radius of +-3 kilometers, a 10 solar mass black hole has a radius of +-30 kilometers, etc. And since this mass is close to infinite, but not infinite, the singluarity is also not infinite small, but can even also vary in volume. Hence you also have something called supermassive black holes with a life span of millions of times the lifespan of the universe and mini black holes with a life span smaller than the lifespan of the universe and as small as the sun.

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Originally posted by John Anderton

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Originally posted by CookieRevised
Black holes not only absorb matter, they also emit stuff.

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Wasnt that a huge controversy !!! Stephen Hawking was wrong and no one figured it out for what ... 40 odd years ??

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yeah but even Stephen Hawking said they emitted stuff. The emittion I talk about is the single radiation beam comming from the polar axis from black hole as it absorbs energy/matter, almost like a pulsar. Not about the radiation discs and other stuff which is emitted from the material itself sucked in.

EDIT: turns out the stuff which is emitted and which I meant is called Hawking-radiation



Ps: [self-split] Theory of relativity
Edited: added url to image