Can a Black Hole create Supernova?

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Can a Black Hole create Supernova???

Is it possible that a Black Hole gets too big, and then just explodes under the pressure of it's own mass. Like a balloon that explodes because we blow it to much. Is it possible that a Black Hole can have a critical mass at which it simply explodes? :confused:
 
Can a Black Hole create Supernova???
You may be interested in the following articles:
http://en.wikipedia.org/wiki/Stellar_evolution
http://en.wikipedia.org/wiki/Supernova

Is it possible that a Black Hole gets too big, and then just explodes under the pressure of it's own mass.
A black hole is characteristic for having a radius smaller than it's event horizon. Any matter coming into the black hole could not escape it. Black holes however can "evaporate" through a process known as Hawking radiation.

Is it possible that a Black Hole can have a critical mass at which it simply explodes?
More mass means stronger gravity. Gravity pulls inward.
 

Janus

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Berislav said:
You may be interested in the following articles:
http://en.wikipedia.org/wiki/Stellar_evolution
http://en.wikipedia.org/wiki/Supernova

A black hole is characteristic for having a radius smaller than it's event horizon. Any matter coming into the black hole could not escape it. Black holes however can "evaporate" through a process known as Hawking radiation.
Just one additional point. As the black hole gets more massive, the rate of evaporation via Hawking radiation slows.
 
So the black holes are growing infinitely??? Are they going to consume all universe?
 
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They won't comsume all the universe, they can continue to feed as long as the have a "food" supply.
 
vincentm said:
They won't comsume all the universe, they can continue to feed as long as the have a "food" supply.
That's kind of contradictory, isnt it?

If they go untill there is no more "food", how can they NOT consume the entire universe, the universe being made up entirely of "food", or matter?
 

Janus

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cDimino said:
That's kind of contradictory, isnt it?

If they go untill there is no more "food", how can they NOT consume the entire universe, the universe being made up entirely of "food", or matter?
To be more correct they will continue to grow as long as the "food supply" exceeds the rate at which they evaporate through Hawking Radiation. As the Universe expands, it cools and the matter distribution thins out. Given enough time, the incoming radiation and matter for even the largest black hole will be less than it emits in Hawking radiation and it will start to shrink.
 

Danger

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cDimino said:
If they go untill there is no more "food", how can they NOT consume the entire universe, the universe being made up entirely of "food", or matter?
You might perhaps be making the common mistake of thinking that a black hole's gravitational influence is vastly greater than that of another, larger body of similar mass. It isn't. If a star of 4 solar masses collapses into a black hole, its gravity is still the same as that of a 4SM star. The field is just incredibly compressed as you approach because you can get so much closer to the centre of mass. For instance, if our sun were to be non-violently reduced to a black hole, the planets would all remain in the same orbits that they have now. The gravitational influence only extends when infalling matter increases the mass.
 
Ahh... Hawking Radiation. Fascinating stuff. So am I correct in saying now that black holes cannot engulf the universe? Or can they, but it requires many of them, or perhaps one that evaporates at a very slow rate, maybe not even at all?
 
Correct me If I'm wrong but if Hawking Radiation is happening, "stuff" actually escapes gravitational force of the Black Hole?!! So that means that it travels faster than light, contradicting the Theory of Relativity??
 
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Danger said:
You might perhaps be making the common mistake of thinking that a black hole's gravitational influence is vastly greater than that of another, larger body of similar mass. It isn't. If a star of 4 solar masses collapses into a black hole, its gravity is still the same as that of a 4SM star. The field is just incredibly compressed as you approach because you can get so much closer to the centre of mass. For instance, if our sun were to be non-violently reduced to a black hole, the planets would all remain in the same orbits that they have now. The gravitational influence only extends when infalling matter increases the mass.
General relativity says that Pressure/Density are also factors in Gravitational infulence of a massive body.This implies that, If our sun were to be some how non-violently reduced to a black hole, the Gravitational influence will be increased by a big factor and hence, Greater curvature of space ==> increase in angular mometum of planets around the event horizon . I honestly believe that the inner planets will eventually spiral-inn and the gaseous atmosphere of the gaseous giants would form the accretion disk...
 

Chronos

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ludi_srbin said:
Correct me If I'm wrong but if Hawking Radiation is happening, "stuff" actually escapes gravitational force of the Black Hole?!! So that means that it travels faster than light, contradicting the Theory of Relativity??
Consider yourself corrected :smile: . Hawking radiation is a quantum effect. Relativity is not imperiled.
 
ludi_srbin said:
Correct me If I'm wrong but if Hawking Radiation is happening, "stuff" actually escapes gravitational force of the Black Hole?!! So that means that it travels faster than light, contradicting the Theory of Relativity??
To expand on Chronos' reply, nothing from inside escapes, it's just replaced by new stuff that's torn away from the fluctuating vacuum of empty space.
 
cDimino said:
Ahh... Hawking Radiation. Fascinating stuff. So am I correct in saying now that black holes cannot engulf the universe? Or can they, but it requires many of them, or perhaps one that evaporates at a very slow rate, maybe not even at all?
Black holes that form from supernovae are very massive and therefore evaporate very slowly because the bigger a black hole is, the slower it radiates energy. To quote Stephen Hawking:

A black hole with a mass a few times that of our sun would have a tempreature of only one ten millionth of a degree above absolute zero. This is much less than the temperature of the microwave radiation that fills the universe (about 2.7 above absolute zero), so such black holes would emit even less than they absorb. If the universe is destined to go on expanding forever, the temperature of the microwave radiation will eventually decrease to less than that of such a black hole, which will then begin to lose mass. But, even then, its temperature would be so low that it would take about a million million million million million million million million million million million years (1 with sixty-six zeros after it) to evaporate completely. This is much longer than the age of the universe, which is only about ten or twenty thousand million years (1 or 2 with ten zeros after it). On the other hand, as mentioned in Chapter 6, there might be primordial black holes with a very much smaller mass that were made by the collapse of irregularities in the very early stages of the universe. Such black holes would have a much higher temperature and would be emitting radiation at a much greater rate. A primordial black hole with an initial mass of a thousand million tons would have a lifetime roughly equal to the age of the universe.
 
Berislav said:
You may be interested in the following articles:
http://en.wikipedia.org/wiki/Stellar_evolution
http://en.wikipedia.org/wiki/Supernova

A black hole is characteristic for having a radius smaller than it's event horizon. Any matter coming into the black hole could not escape it. Black holes however can "evaporate" through a process known as Hawking radiation.

More mass means stronger gravity. Gravity pulls inward.
Yes,but the Hawking radiation has never been proven.What's the point of discussing about black hole evaporation,if it has never been proven,only in mathematics?
What if black holes last forever???Although,I personally think they should.
 

pervect

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No-where-man said:
Yes,but the Hawking radiation has never been proven.What's the point of discussing about black hole evaporation,if it has never been proven,only in mathematics?
What if black holes last forever???Although,I personally think they should.
The point of the discussion is to describe how current theory predicts black holes should act. This is how science advances - predictions are made according to a theory, then they are checked experimentally. It is important to have an actual theory that predicts results, and not to just have people making things up as they go along based on some sort of guess, gut feel, or other prejudice. Random guessing based on personal prejudices does not significantly advance science.

The very short answer to the original question

Is it possible that a Black Hole gets too big, and then just explodes under the pressure of it's own mass. Like a balloon that explodes because we blow it to much. Is it possible that a Black Hole can have a critical mass at which it simply explodes?
is simply "No, not according to general relativity". But that's not really much of a discussion, so people have very thoughtfully explained in much more depth.

At the moment we are not in any position to check for the emission of Hawking radiation from black holes in the near future, though experiments have been proposed (but not yet carried out AFAIK) to check for a very similar effect known as Unruh radiation.
 
G

Gerinski

Danger said:
You might perhaps be making the common mistake of thinking that a black hole's gravitational influence is vastly greater than that of another, larger body of similar mass. It isn't. If a star of 4 solar masses collapses into a black hole, its gravity is still the same as that of a 4SM star. The field is just incredibly compressed as you approach because you can get so much closer to the centre of mass. For instance, if our sun were to be non-violently reduced to a black hole, the planets would all remain in the same orbits that they have now. The gravitational influence only extends when infalling matter increases the mass.

Yaaks said:
General relativity says that Pressure/Density are also factors in Gravitational infulence of a massive body.This implies that, If our sun were to be some how non-violently reduced to a black hole, the Gravitational influence will be increased by a big factor and hence, Greater curvature of space ==> increase in angular mometum of planets around the event horizon . I honestly believe that the inner planets will eventually spiral-inn and the gaseous atmosphere of the gaseous giants would form the accretion disk....
Who's right on this? I think Yaaks is, but can someone reconfirm?
 

Chronos

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Yaaks is wrong. If you magically collapsed the sun into a black hole, it would have absolutely no effect on planetary orbits. Not even Mercury would so much as quiver.
 
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