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Author Topic: Can Black Holes Just Swallow Stuff Forever ?  (Read 2904 times)

Offline neilep

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Can Black Holes Just Swallow Stuff Forever ?
« on: 25/07/2007 22:35:43 »
Black Holes are well hungry !!

Rumours exist that they can eat Triple Whoppers !!
..I mean come on !!.....that's almost too hard to comprehend !


....but seriously.....if a Black Hole had an infinite source of matter would it just continue eating away ?...would it not eventually eat itself ?...or the whole universe ?....is there a limit to a black holes capability ?


 

Offline DoctorBeaver

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #1 on: 25/07/2007 22:44:39 »
I read that they can eat 3 Shredded Wheat too!  [:0]

But seriously folks - black holes actually evaporate so that over time they regurgitate everything they've swallowed (it was obviously my ex-wife's cooking!).  :D
 

Offline neilep

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #2 on: 25/07/2007 23:12:56 »
I'd heard of the evaporation thing....hard to figure out how something with such an incredible magnitude of gravity can gradually release bits of itself...!!..how does that happen  ?

I wonder what the final moments of a black hole is like ?...any speculations would be nice !

LOL...did your ex wife ever make dumplings ?....if she did...she must have given the recipe to my wife as her dumplings capture things in orbit they're so dense......



 

Offline Karen W.

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #3 on: 25/07/2007 23:18:55 »
I know nothing about black holes.. give me the low down on a black hole!exactly what is it?
 

Offline DoctorBeaver

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #4 on: 25/07/2007 23:40:26 »
A brief description of black holes for beginners.

1) They're black
2) They're holes

It's all down to escape velocity. Escape velocity is the speed at which an object without propulsion would have to be travelling to escape from a gravitational field. The Earth's escape velocity is around 7 miles per second. An object travelling upwards at a speed less than that would fall back to Earth.

Now, if the Earth were compressed into a smaller volume, the gravitational attraction at its surface would increase. That is because gravitational attraction of an object diminishes as the inverse square of the distance from the object. So, if you halve the diameter of the Earth, it's gravitational attraction at the surface would increase fourfold. Halve it again and gravity at the surface increases to 16 times the original. As the gravitational attraction increases, so does the escape velocity.

So, if an object is compressed enough there will come a point where the gravitational attraction will be so strong that the escape velocity will be equal to, or greater than, the speed of light. As nothing can travel faster than light, nothing would be able to escape the object's gravity. That includes light itself. If no light can escape then the object will appear black.

The distance from the centre of a black hole where the escape velocity equals the speed of light is known as the event horizon. Anything that crosses the event horizon will be on a 1-way trip to the centre of the black hole; there is no escape.

When a star with mass greater then 5 times that of our sun collapses, theory states that it should form a black hole.
 

Offline Soul Surfer

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #5 on: 26/07/2007 00:55:29 »
Stephen hawkings prediction for the ultimate fate of the universe is to be one black hole that will then spend an eternity evaporating.  The end of a black hole is not very spectacular because by the time it radiates brightly there is very little mass left and it would be quite hard to detect one exploding at any distance.
 

Heronumber0

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #6 on: 26/07/2007 01:13:31 »
Is there anything at t'other end of a black hole? E.g. a white hole? Or can it spew the matter into another Universe?
 

Offline Karen W.

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #7 on: 26/07/2007 01:52:42 »
Wow that is confusing..Hee hee I have to read it several times..
 

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Can Black Holes Just Swallow Stuff Forever ?
« Reply #7 on: 26/07/2007 01:52:42 »

 

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