Slashdot Mirror
Why Some Supermassive Black Holes Have Big Jets
astroengine writes "Some of the supermassive black holes at the centers of galaxies have powerful jets blasting from their poles, and others have weak jets, but many don't have jets at all. Why is this the case? In new simulations carried out by astronomers at NASA and MIT, it would appear that the way in which the black hole spins relative to its accretion disk may be a contributing factor. Strangely enough, the results indicate that if the black hole rotates in the opposite direction to its accretion disk, the most powerful jets form. The region between the black hole event horizon and the accretion disk still baffles scientists, so these simulations are very speculative, but the results seem to match what radio astronomers are seeing in the cores of active galaxies. Perhaps it's time to fire up that event horizon telescope!"
Is there a name for the theory that matter is being sucked out of our universe as fuel for another?
Kind of hard to reconcile since black holes increase in mass as they draw in matter (aka mass.)
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
They increase in mass, yes but does their size increase? Where does the matter go if it's all compressed to a singularity? Are all the atoms just spaghettified, stacked one on top of the other in some infinitely tall, infinitely narrow well?
I have only a most basic grasp of cosmology but it's an interest of mine and I recall watching something on documentary heaven to the effect that black holes may well be a universe of their own. To be honest the very idea of a singularity still baffles me: it seems as though you start with an assemblage of simple, dull matter and in the blink of an eye any semblence to matter as we know it disappears and you're left with something that - to me at least - sounds like a feature of space itself.
Exactly what happens between the instant when you have a very, very dense lump of matter and an infinitely dense one? It seems an infantile question but where did all the matter go? Or was it transformed into something else that has mass but no size? Thinking about it gives me a headache and usually leaves me pondering whether any particles really have a physical size or if it's just another consequence of our limited view of the Universe.
If God forks the Universe every time you roll a die, he'd better have a damned good memory.
Actually, math only breaks down at the Event Horizon, and physicists pretty much ignore that one point and continue on. Theoretically, due to all calculations, time at the singularity proceeds just like it does for a non-relativistic observer. And you can in fact, calculate the amount of time it would take for you to reach the center of the black hole, though somebody watching you would say it took an infinite amount of time since they see you as stopping at the Event Horizon. But to you, you actually reach the Singularity.