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...otherwise known as "ridiculously stupidly big"
Will we disappear into it? 
Is that blackhole bigger than J-Lo's bottom?
What would that be in elephants or blue whales, the normal units for awfully big things?
Will we disappear into it?
Quote...otherwise known as "ridiculously stupidly big" Is that blackhole bigger than J-Lo's bottom?
How come we on one side say that there never will be any mass reaching past the event horizon and on the other treat black holes as growing? Where will all that extraneous mass be if so?
The bigger the black hole, the bigger the gravitational field and the faster it can pull in matter - but that same huge gravitational gradient means that the same matter can release huge amounts of radiation as it falls, blasting other matter further away
Similarly, if electrons and other fundamental particles were actually point particles, they would be behind their own Schwarzchild radii and instead of atoms we'd just have a very large black hole. The amount of an electron's charge and mass that is inside a zero-size volume is zero, which is why QCD gets nonsense when it assumes it isn't.
If you think of a photon, then that is said to be both sizeless as well as massless. That would make for a very strange black hole
Still the question remains; how can a black hole gain mass if nothing can get past the event horizon?I still suspect there is something not yet discovered that prevents anything from reaching the singularity. It will always be approaching it; never reaching it; like repeated instances of getting half way there.
There are those infinities again!Remember, time dilation does not affect the object falling into the black hole. In its own frame of reference it will still fall in at the rate expected. It is only to an outside observer that it will appear to fall slower & slower. That means that in the frame of reference of the falling object, the blackhole does gain mass.
If the observer is watching something time-based happen on the falling object though, it will appear as though that thing will be happening more slowly. However, to the object itself, in it's local frame of reference, time will seem to be passing at the normal rate and it's everything else that seems to be changed.
You're referring to what's known as "The Blue Curtain", where the time dilation is so great to an outside observer that it appears to stand still and matter seems to accumulate at the event horizon. Light accumulating in this way is infinitely blue-shifted (infinities again grrrrrr).
Does this mean that Disney's Black Hole is not authoritative ?
Quote from: neilep on 18/03/2009 02:52:25Does this mean that Disney's Black Hole is not authoritative ?Well, old Walt was always more of a biologist than a physicist.
It's not emerging, it's heading in. I'm not sure of the mechanics behind it, I just read about it. If I recall correctly it's more to do with time dilation.
...From the viewpoint of a distant observer, an object falling into a black hole appears to slow down, approaching but never quite reaching the event horizon: and it appears to become redder and dimmer, because of the extreme gravitational red shift caused by the gravity of the black hole. Eventually, the falling object becomes so dim that it can no longer be seen, at a point just before it reaches the event horizon. All of this is a consequence of time dilation: the object's movement is one of the processes that appear to run slower and slower, and the time dilation effect is more significant than the acceleration due to gravity; the frequency of light from the object appears to decrease, making it look redder, because the light appears to complete fewer cycles per "tick" of the observer's clock; lower-frequency light has less energy and therefore appears dimmer, as well as redder.
I read it in a book by John Gribben, the author of many science books. I borrowed it from a library about 4 years ago.
And 'red blue shift' will be 'equalized' as it moves around I suppose?Or, will it? Depending on where its finally comes from meeting your observer??
I think I've remembered what that Blue Curtain thing is all about. It's from the perspective of an observer falling into the EH. Does that sound better?