Black Holes

[pgrmdave]

What percentage of stars could become black holes? And do black holes eventually die, or would they exist forever?

[bumab]

I'm not sure the percentage, but balck holes do eventually die- they evaporate through Hawking radiation, I believe. I'll go look it up.....

[UncleAl]

A star's evolution is determined by its mass. If the star is one of a binary system, it can evolve and capture mass from its partner, changing its ultimate destination (including Type I supernovae). Look it all up in Google. The world is raining knowledge. Don't use your soup bowl as a rain bonnet.

Small stars (the Sun) will eventually bloat, blow off their outer shell of mass, and leave behind a white dwarf that will slowly cool. It's boring overall and tough on the planets.

Heavier stars will go Type II supernova: When their cores reach iron by fusion there is no further energy to be had to keep the star inflated, temperature vs. gravitation. The extraordinary temperature of that iron core plus the increasing pressure lead to sudden photodisintegration of the iron nuclei - and that is endothermic! Suddenly, nothing is holding the star inflated. The core squeezes into neutronium with a huge blast of neutrinos (90% of the total energy emitted - the big flash to follow is piddles) as electrons and protons combine. What happens next depends on the amount of mass present.

1) The remaining core is around 1.5 solar masses. As the outer layers blow off into a Type II supernova, the core is stable as a very hot, very rapidly rotating neutron star.

2) If the core is much larger, even Pauli exclusion can't keep it inflated against gravitational pressure. The neutronium collapses all the way to a singularity surrounded by a black hole.

However... SN1987a which is relatively close by and very visible, star to Type II supernova to current remnant,

http://csep10.phys.utk.edu/guidry/violence/sn87a.html
http://zebu.uoregon.edu/~soper/StarDeath/sn1987a.html
http://chem.tufts.edu/science/astronomy/SN1987A.html

left no neutron star or black hole visible to date, even by inference. This is a curiosity with no explanation.

[maddog]

I remember from my Astrophysics class that mass limit of 3.1 solar masses for a star would have as part
of the eventual supernovae would proceed to a black hole (thereby bypassing the neutron star outcome).
You have tell-tale signs a sizeable quantity of X-Rays from the accretion disk.

maddog

ps: Text: Astrophysics, Martin Harwitt

[Odin]

Well Blackholes do not exist. If you look at Einsteins Special Theorom and the equation E=mc^ you will see it is nothing more than a hyped up creation from Newtons Theory of Potential Energy.
The theory of Einstein is merely that if an object had an infinite mass it would have an infinite energy field.The only thing is that the object would have to be travelling at the speed of light. Even if only in rotation by the collapsing upon oneself the mass would become so small it would no be able to aquire an infinite mass as mass is existance in substance. The smaller the collapsed star became from rotation the energy field would increase but only to a certain degree before its mass would become less than one and the collapsed star would not be able to sustain its momentum or energy levels and the collapsed gases would expand again but since the star is now inactive would just dissipate into the universe

[InfiniteNow]

Originally Posted by Odin

Well Blackholes do not exist.

How then do you explain those intense gravitation wells which impact the space around them but emit no light?

[ronthepon]

Originally Posted by Odin

Well Blackholes do not exist....
...
The theory of Einstein is merely that if an object had an infinite mass it would have an infinite energy field.The only thing is that the object would have to be travelling at the speed of light. Even if only in rotation by the collapsing upon oneself the mass would become so small it would no be able to aquire an infinite mass as mass is existance in substance. The smaller the collapsed star became from rotation the energy field would increase but only to a certain degree before its mass would become less than one and the collapsed star would not be able to sustain its momentum or energy levels and the collapsed gases would expand again but since the star is now inactive would just dissipate into the universe

Well, if you can argue against the infinite mass concept, go ahead, you're right.

However, black holes do not have infinite mass.

The rest of your post is a bit tough to understand for me, are you trying to convey that as the star or whatever body gets smaller, some how the mass gets less? Because that would not be true.

[God's servant]

Originally Posted by Odin

Well Blackholes do not exist.....

And you can prove this how??? All you have there are theories. To have a truth you have to have proof. You have no proof, just theories.

[Little Bang]

You right ron, not infinite mass but infinite density.

[WillieB]

Ron and Little Bang:

In your heart of hearts, do you really believe in an infinitely large gathering of mass contained within an infinitely small point. If so you are a captive of esoteric mathematics extended to an infinitely ridiculous extent.