Before I start, let me state that I'm not pushing any explanation of my own, because I don't even have one. Which is unsurprising, I guess, since I'm not a physicist. I genuinely get a brainfart just trying to think about how it swallows matter, and I'm hoping someone more knowledgeable can help me understand it.
Now I'm not asking about the whole thing about how many solar masses you need and all that, because that part I know already.
I'm also not asking about matter falling below the event horizon, and the Schwarzschild radius, 'cause that part is clear too.
But, here's the thing I don't get: how it gets an event horizon in the first place, and how does it get more mass.
And I'll start by stating how I understand it. Which is probably wrong, since I can't get anywhere with it. But maybe it will help someone spot and point out to me the point where I'm going into gaga land with it.
Schwarzschild calculated that limit for an eternal black hole. It has always existed and it always will. Well, that one is easy, 'cause you don't have to deal with it forming in the first place. And I know physics simplifies the model to what's relevant for the problem at hand, and I have no problem with it. (Not that it would matter to anyone else if a layman did have a problem with it, mind you.) Just it doesn't answer MY problem.
And my problem stems from the fact that we don't have anything that always existed, since the universe ain't that old. So it has to have formed at some point.
So let's say some chunk of matter swirls down the drain... err, accretion disk, and falls down into the black hole. From its point of view, of course, that happens in a finite time. From OUR frame of reference, though, time dilates increasingly the closer to the event horizon it gets, and it goes asymptotically towards the actual event horizon. So essentially it takes an infinite time for us to see it fall in. It only gets there at +infinity on the time axis.
And it doesn't help if I put it on a pinrose diagram, 'cause that line is still at infinity.
Essentially if I don't start with a pre-existing black hole, it sems to me like I can only get a FUTURE black hole, infinitely into the future. The matter never actually gets inside it, information never disappears into it, it just gets stuck at an apparent horizon, in infinitely slow motion.
So... how did it form in the first place? How can I end up with a present black hole, instead of a future one? Where am I thinking all wrong?
Now I'm not asking about the whole thing about how many solar masses you need and all that, because that part I know already.
I'm also not asking about matter falling below the event horizon, and the Schwarzschild radius, 'cause that part is clear too.
But, here's the thing I don't get: how it gets an event horizon in the first place, and how does it get more mass.
And I'll start by stating how I understand it. Which is probably wrong, since I can't get anywhere with it. But maybe it will help someone spot and point out to me the point where I'm going into gaga land with it.
Schwarzschild calculated that limit for an eternal black hole. It has always existed and it always will. Well, that one is easy, 'cause you don't have to deal with it forming in the first place. And I know physics simplifies the model to what's relevant for the problem at hand, and I have no problem with it. (Not that it would matter to anyone else if a layman did have a problem with it, mind you.) Just it doesn't answer MY problem.
And my problem stems from the fact that we don't have anything that always existed, since the universe ain't that old. So it has to have formed at some point.
So let's say some chunk of matter swirls down the drain... err, accretion disk, and falls down into the black hole. From its point of view, of course, that happens in a finite time. From OUR frame of reference, though, time dilates increasingly the closer to the event horizon it gets, and it goes asymptotically towards the actual event horizon. So essentially it takes an infinite time for us to see it fall in. It only gets there at +infinity on the time axis.
And it doesn't help if I put it on a pinrose diagram, 'cause that line is still at infinity.
Essentially if I don't start with a pre-existing black hole, it sems to me like I can only get a FUTURE black hole, infinitely into the future. The matter never actually gets inside it, information never disappears into it, it just gets stuck at an apparent horizon, in infinitely slow motion.
So... how did it form in the first place? How can I end up with a present black hole, instead of a future one? Where am I thinking all wrong?
via International Skeptics Forum http://ift.tt/2w7oYm3
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