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Pjpic
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When two black holes collide, do the singularities orbit each other, does one evaporate into the other, or is something else happening.
Pjpic said:If two singularities coaleasced wouldn't you end up with only one singularity? But I was under the impression (quite likely wrong) that, once the singularity formed, it was permanent (nothing can escape from it).
Pjpic said:If you start out with two singularities (niether of which can be destroyed), how can they coaleasce into one singularitiy without one of them no longer being a singularity? Whereas it is easy to see how two drops of water can coaleasce into one drop.
One does not evaporate into the other. Evaporate is a term with a particular meaning when it comes to BHs. A lone BH, if given enough time (a LOT of time) can, in theory, literally evaporate - it loses mass until it disappears. How that happens is another story, which we can address momentarily.Pjpic said:I must have misunderstood the posting that began with "that is correct". This misunderstanding makes the issue, about how an inviolate object could lose its individuality in merging with another object, moot and the second option of the original post to be the, relatively, most accurate.
Pjpic said:*When two black holes COLLIDE (not orbit or anything) the two singularities will eventually merge into one.
This sounds to me like 1 +1 =1. Is one of the black holes being absorbed by the other? As if they were two hurricanes colliding and one eye gets disorganized (destroyed) while the other eye just gets stronger. Or is it as if both eyes lose their round shape before forming one new center. In either case wouldn't at least one of them be losing their curvature (which I thought I heard was impossible - except perhaps through evaporation).
Pjpic said:I think the misunderstanding comes from the "nothing can excape the event horizon" and the "singularity" descriptions. I must be conflating these into the 'singularitiy can't excape' , which it apparently can if two central gravity points are changed into one central point. As when a meteorite lands on earth.
Pjpic said:I think the misunderstanding comes from the "nothing can excape the event horizon" and the "singularity" descriptions. I must be conflating these into the 'singularitiy can't excape' , which it apparently can if two central gravity points are changed into one central point. As when a meteorite lands on earth.
Arch2008 said:words
pzona said:Astrophysics really isn't my strong area, but this caught my interest. When you say the two black holes merge to create a larger black hole, I assume you mean larger in terms of mass, since black hole refers to a singularity (right so far?). Does this mean that the event horizon expands? If so, I would imagine that more objects become subject to the black hole's gravity, which increases the mass further, which in turn expands the event horizon even more, which creates a cycle. This cycle (as I see it anyway), should continue until the universe is reduced to a singularity. This doesn't make sense to me (for good reason I'm sure). Is my flaw in my understanding of the expansion of the event horizon (if it expands at all), or is it in my lack of consideration for the relativistic effects inside the event horizon?
Pjpic said:Could you tear apart a black hole if you put it between two other larger black holes?
Pjpic said:When a massive black hole and a microscopic black hole merge event horizons, are both central masses immediately considered to be combined into one or does the smaller one have to fall for a while?
Yes. The mass of the final BH is equal to the sum of the masses of the two intial BHs.pzona said:When you say the two black holes merge to create a larger black hole, I assume you mean larger in terms of mass, since black hole refers to a singularity (right so far?).
The event horizon expands, yes. But the event horizon is not a "thing". And it is definitely not the "thing" that is doing the attracting. It is the mass that is doing the attracting.pzona said:Does this mean that the event horizon expands? If so, I would imagine that more objects become subject to the black hole's gravity,
Yes. You are thinking of the event horizon as if it is the boundary of the BH - as if things behave differently depending on which side of the boundary you are on.pzona said:Is my flaw in my understanding of the expansion of the event horizon
These are extremely insightful and inquisitive questions. The kind PF members fight over to be the first to answer.pzona said:I apologize in advance if these are dumb questions. If they are, let me know and I'll read more on black holes before posting in this section again.
Actually, it's somewhere between [tex]\sqrt{m_1^2+m_2^2} < M < m_1+m_2[/tex].The mass of the final BH is equal to the sum of the masses of the two intial BHs.
Ich said:Actually, it's somewhere between [tex]\sqrt{m_1^2+m_2^2} < M < m_1+m_2[/tex].
sylas said:Any particle takes a finite proper time to proceed from the event horizon to the singularity. It makes no difference whether the falling particle is a black hole or not; the time is the same.
Well, the singularity is theoretically a point so it's not going to "stretch".Pjpic said:As the microscopic BH falls into the massive BH, is the microscopic BH subject to the "spagetti effect"?
pzona said:DaveC-
Thanks for the response. I have another question regarding the gravitational field of the black hole. If the mass increases (say, from merging with another black hole), doesn't that increase the strength of the gravitational field as a whole, relative to the distance from the black hole? For instance, if a star was x distance from the black hole, and the gravitational field was some arbitrarily small measure of force from overcoming the star's inertia and "sucking it in," and the BH's mass increased, wouldn't this mean that the gravitational strength at x distance would increase? And if so, wouldn't the star be drawn into the black hole, increasing its mass and thus expanding its gravitational field (relative to distance of course) in the same way again? This is what I meant by a runaway effect.
pzona said:DaveC-
Thanks for the response. I have another question regarding the gravitational field of the black hole. If the mass increases (say, from merging with another black hole), doesn't that increase the strength of the gravitational field as a whole, relative to the distance from the black hole? For instance, if a star was x distance from the black hole, and the gravitational field was some arbitrarily small measure of force from overcoming the star's inertia and "sucking it in," and the BH's mass increased, wouldn't this mean that the gravitational strength at x distance would increase? And if so, wouldn't the star be drawn into the black hole, increasing its mass and thus expanding its gravitational field (relative to distance of course) in the same way again? This is what I meant by a runaway effect.
A black hole collision occurs when two black holes merge together due to their intense gravitational pull. This phenomenon was first predicted by Albert Einstein's theory of general relativity.
Black hole collisions can occur when two black holes are in close proximity to each other. As they orbit each other, they emit gravitational waves which cause them to lose energy and eventually merge together.
During a black hole collision, the two black holes will spiral towards each other and eventually merge into a single black hole. This process releases a tremendous amount of energy in the form of gravitational waves.
Yes, we can observe black hole collisions indirectly through the detection of gravitational waves. These waves can be detected by specialized instruments such as the Laser Interferometer Gravitational-Wave Observatory (LIGO).
Black hole collisions can provide us with valuable information about the nature of gravity and the behavior of black holes. They can also help us better understand the origins and evolution of our universe.