Black holes

http://space.about.com/cs/blackholes/a/blackholesinfo.htm

"Large" in the sense of space occupied is meaningless applied to black holes; a black hole is a dimensionless point of mass concentration sufficient that gravity prevents the escape of radiation therefrom - that's what makes them black holes. However, a black hole is surrounded by an event horizon, essentially the demarcation line from inside of which nothing escapes, but which from the outside can, depending on the mass of the black hole at the center, occupy cubic light years of space. As matter is drawn into a black hole, it accellerates, reaching, as it attains the event horizon, relatavistic speeds - that is, velocity of an appreciable fraction of the speed of light. A result of this accelleration is that matter collisions occur, much as in, but on immensely greater scale, nuclear colliders here on earth. These collisions release tremendous energy - they are, in effect, nuclear explosions - and this energy is radiated in all directions, some of it away from the event horizon. We see this energy in a variety of forms - visible light, ultraviolet, infrared, and other electromagnetic radiation, which may be observed in many forms, from jets of energy extending light years from the invisible center of mass to an overall glow caused by heated, exited gas and dust surrounding the center of mass. And while black holes are not directly observable - they're "black", after all - not only can we see and measure their effect on matter at their fringes, we can observe and measure their effect on stars in their vicinity, and we can see the effect black holes have on light, as their gravity bends, or "lenses" light.

In short, a black hole itself has no size, but its effect envelope can be staggeringly immense.

From outside the event horizon you can only tell three things about a black hole---mass, charge, and spin (angular momentum).

The black hole itself is a singularity, a point in space without dimension.

Rap

Completely unqualified to comment, i just want to express my appreciation for the comments of those who are able to make a sensible response.

Marvelous post, Heliotrope--you lost me completely after the statement about the amount of mass the singularity has captured. But i'm willing to take your word for this, unless and until someone shows up to shoot you down.

Can't shoot down reality.

That's reality is it?

Sounds a bit shamanistic to me.



For non scientific readers that's about the size of an average cherry pip.

Black holes
Thank you all so much for some truly breathtaking answers! One-third of an inch, eh? And we think the earth is crowded now!

The concept of a "singularity" without the usual physical dimensions is difficult to conceive of, on an everyday level. But I'm sure there is much out there in the universe, and all around us for that matter, that we can't really grasp with our limited human understanding.

I'm brand new to this bb and am truly impressed!

*looks up startled and hurredly hides limp chicken behind back while smiling ingratiatingly*
Shamanistic ?
*thumbs ancient, rune covered bones in left hand*
Moi ?




Or 2.0736x10^-6 of a standard Elephant.

How can there be a standard elephant - does one take the Asian or the African as the nominal base reference, and why?

Neither of them.
This is a Standard Elephant taken to be the average of all elephants. It is very unlikely that there will be a living elephant that conforms exactly to the specifications of the Standard Elephant.
After all that's what standards are about.

That's a good example of the standard evasive answer

This thread has distinct promise.

It is a goofing off thread which sets new standards for goofing off. The old goofing off standard being now a bit old fashioned not to say passe.

You could easy get a standard elephant. You take 1,000 elephants selected randomly from the elephant population like they do with surveys to see what % of the pop'n has athlete's foot in order to decide whether a turn can be made out of a new cream with a new name and you put them to sleep humanely under the supervision of humane inspectors.

Then you grind them up in a mincer and mix them up and divide the resultant homogeneous mush into x portions where x is the number of elephants you started with.

Let x be a standard elephant. QED.

If you wanted to find some offset you could can the lot in 4oz portions and market them under a snappy new name with a young career woman showing a bit of cleavage saying how delicious it was and you might get some of your money back if you picked the young career woman who took the public's fancy.

If it was a success you would have to get another 1,000 elephants or go out of business which wouldn't be very American.

No no no you don't go out of business.
You get a government grant to do further research into the important implications of not having a Standard Elephant on grasslands and savannah which are of vital importance to those wishing to drive their newly aquired soft-roader SUV on so they can feel like they got their money's worth.
And of course to keep your newly aquired shareholders from baying at your door you get involved in various black projects in order to hide your misappropriation of section resources from the public and all the while beating them over the head with the fact that they are not conforming to the Elephant Gold Standard.
This distracts them and allows you to syphon off the cash and then retire to the Cayman Islands with your friend Nellie.

One presumes Nellie is a properly authorised and constituted standard Nellie who fully appreciates unimaginable density manifesting itself in a dimensionless loci within an event horizon approximately the size of a cherry pip.

Unfortunately not.
This was the reason for seeking black project tenders and government sanction so enable Nellie to be hidden from the public eye and thus not cause massive outcry regarding the "one rule for the public and another rule for them" situation.
The embezzelment of funds was merely an opportunist act that would also be covered up by the government should the press become involved.

The right of the people to keep and bear Nellies shall not be infringed.

Keep Nellie away from the telephone, trunk calls are costly.

timber wrote-



Don't be so bloody ridiculous timber.

That rule was written for sodbusters,spouses of sodbusters and progeny of sodbusters to the total of a paltry 15 million when Caractacus was a lad and it is completely anachronismic to attempt to apply it to nearly 300 million sophisticated scientists living an intellectually fulfilling life complete with all the modern conveniences which one rightly expects to be necessary in such circumstances and in which a sod is viewed as an abstraction.

The Cayman Islands are a different kettle of fish entirely being a British dependency and situated in The Rest OF The World.