What would happen if two gravitational singularities meet

There are some lessons to learn from NGC 6240: Two black holes "push each other" for several millions of years and being nurseries for stars. And of course this will eventually merge into something new, if there is nothing, there is entropy principle. OK, but this does not require to reject the fact that these two black holes have been applying some physics and some forces to rotate around each other for hundreds of millions of years. They don't suddenly come accross and become one in the blink of an eye: It takes considerable amount of time. Those forces and relations do not care about the limits of our understanding about them. They reject to apply homemade gravity to vacuum each other; no, they use time and space differently.

What can I say for 3C 75: "Two supermassive black holes, once the centers of the progenitor galaxies, in a distance of 25 000 light-years now orbit each other." I stole this sentence from an astronomy site...

In the very beginning of my speculation, I said that maybe they are pushing each other. I said maybe a magnet like pushing. I never claimed anything about the spacetime geometry of this force, yet it works for long time.

Perhaps you should google "Black Hole Merger"...

 

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When two black holes encounter each other, they will do one of three things;

1/ they may encounter each other head on, in which case they will simply merge, and most of their mass-energy wil be aborbed into a single black hole with almost the same mass as both holes combined. But head-on encounters would be rare.
2/ The two holes could swing past each other on hyperbolic curves, interacting somewhat but essentially remaining the same. If they lose any energy during the encounter they will be slightly smaller than before, but otherwise they will just carry on travelling through space, albeit on a slightly different path.
3/ The two holes could go into orbit around each other.

To go into orbit around each other the two holes need to lose some of their forward velocity; some mechanisms for this are discussed here
http://www.space.com/scienceastronomy/merging_backhole_021119.html
for two galactic black holes approaching each other (each with a halo of ordinary stars in orbit around it)

Stellar mass black holes could do the same trick by transferring momentum to their accertion disks, if any.

Once the two holes are in orbit around each other they will lose energy by gravity radiation, and eventually get so close that their event horizons and/or ergospheres combine. They will continually lose energy via gravitational waves up to this point; and during the subsequent merger the two holes will lose more energy in this way. The end result of such a merger would be a single black hole, considerably smaller in mass than the combined masses of the two original holes. Remember that as seen from outside the event horizon, there is no difference between the energy and mass content of the hole(s), so any energy they lose in the process results in a drop in total mass.

 

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No they don't.
Being in orbit has nothing to do with a "push", the forces are still attractive.

Perhaps you should learn some physics.

 

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For gravitational bodies:

Each gravity subject (That could be moon, planet, star, galaxies or black holes) in space has its own unique body, mass, totality, sum of energy, characteristic, position, movement. We can call sun’s gravity and earth’s gravity. We also know that they obey bigger gravitational body, Milky Way.

Each black hole must have a mass to occupy a place in the space. Their mass creates a collapsing horizon where even light can not escape from it. But they have limits and individual characteristics like any other space object. When they meet other masses, they interact according to their position and the position of other object’s speed, velocity, direction, mass and dynamics (whether it is a cold planet or burning star, or the centre of a galaxy). A dance starts for millions and billions of years. Each entity has its own internal mechanism. Sun will explode before the Milky Way and earth has nothing to do with it, because earth has its own gravity to deal with. Each and every dance has some characteristics because each partner brings different things to the action. If you are interested in what we do not know about gravitational waves, you can always visit Nasa. (“Dynamics of Super Massive Black Holes”http://lisa6.gsfc.nasa.gov/conf/lisa6/presentations/Tue_0940_Sigurdsson.pdf)

You are assuming that any twin entity (twin planets, twin stars, twin galaxies) will necessarily collapse to each other. Wrong. If they are not close enough they can be “separated” from each other, too. Each entity has its own mass and gravitational collapse, because it has its “separate” concentration in existence. This is why we call temporal situations as “this planet”, “that black hole”. If you accept that earth is falling down into sun’s gravity while moon is moving away from earth, you must accept that the role of the gravity depends on what is exercising it, and what is the relation to other entity.

Perhaps you should develop something that I really don't know what it is.

 

Perhaps you should go away for longer and learn something instead of simply cutting and pasting stuff that has no relevance.
This is my very first post in this thread:

Note the words "nothing else" - i.e. assuming they're not subject to any other forces: which would include tangential motion.
Also look at the wording of the OP: there is no suggestion that there's any forces or motion to be considered OTHER than those from the black holes themselves.

Or, to use your wording "If they are not close enough they can be “separated” from each other, too" which is correct, BUT that separation will only remain IF there is no other force/ motion/ condition to take into account. In the case of the Earth orbiting the Sun it's the Earth's speed AROUND the Sun that stops it being dragged in: remove that speed and the Earth is a cinder, remove gravity and the Earth disappears into the big dark bits...

Perhaps you should resolve to REALLY know what you're talking about, because so far all you've done is demonstrate repeatedly that you don't know anything about this.

 

"If two black holes are in a reasonable distance from eachover in spae and exert the same force and energy, what would happen? I think maybe these two unstopable force can either collapse on eachover or cancel their effects out."

This is what OP asks for: “in a reasonable distance” from each other. And “same force and energy”, no one is including anything else, and you do not need to create hypothetical conversation like anyone introduced any extra force into the discussion; no, there is no such a thing. I gave you the examples of moon and earth just for the sake of giving an example to cosmologic diversity of the universe, not to include any other force into the equation. In this discussion, there is no other force, there are two black holes and nothing else. And the title of original post asks: “What would happen if two gravitational singularities meet?” In order to eliminate the possible confusion, it also states that “same force and energy”. Although it is utterly tough task to find such “equal” forces in real universe, we should accept this hypothetical situation for the sake of this discussion.

However, there is still no guarantee that two black holes would necessarily collapse, because we do not know what this “reasonable distance” is, depending upon their sizes and temporary positional agreement. We can deduce a mathematical formula which says “if these two have X amount of gravitational energy and they have Y distance between them, so merger will happen”. This is undeniable, and there are astrologic evidences that this math works in reality. But this is not the answer for the OP, because it asks for general possibilities in reality, where many different things happen, and each one can also be explained by matching mathematics. If two black holes meet at certain distance, which is not enough for a merge, they would not merge, simple as that. Without this “distance” concept, neither time and space, nor your physics make any sense.

Your claim “If they're in each other's gravitational influence (and there's nothing else acting on them) then they'll move toward each other and merge.” is a wrong assumption. Because they can also form twin galaxies at certain distance, which may be enough for twin formation (and not going for their own separate directions), but not enough to merge in the future. You are claiming that once “they're in each other's gravitational influence” so they will necessarily collapse to each other. Probably you would also claim that if there is a distance between them preventing from their merger, it is because there must be an involvement of another force in the scenery. These two gravitational forces, otherwise, must necessarily collapse to each other. So I ask, what is this force that prevent them collapsing to each other, if not their own relational and temporal agreement depending upon only their own gravitational body movements?

You can make sense in an isolated condition, not for the real possibilities and happenings in the universe.

 

And I asked that in my first post.

Then if there are no other forces introduce the two will merge into one.
Note the thread title "if they MEET".

Except that those examples DO have other forces/ motions etc to be taken into consideration.

In which case the two will merge and form a larger black hole.

As stated BY ME: if the reasonable distance means they are within each other's gravitational influence then they WILL meet and merge.

Actually it IS the answer to the OP.

Incorrect.

The only reason that the black holes in your example don't meet and merge is because there ARE other forces acting on them.

That's true, I would claim it, because that's what would happen.

You aren't making sense at all.
My first post clearly stated "no other forces" which you yourself have said is reasonable for the purposes of this discussion.

And as for "real possibilities and happenings in this universe" have you also just not written "we should accept this hypothetical situation for the sake of this discussion."

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I repeat the question of "what is this extra force that create non-mergin twins?" Is it external to the gravitational forces of black holes? Is is dark matter, what is it? We accept hypothetical situation to understand what keeps two bodies separate, as much as to understand what makes them merge. You are still claiming that if there was not any other force, these two can not position themselves in certain distance without creating a single black whole. You can isolate every other forces and effects to analyse gravity in its pure sense in theory, but is there any real example in universe where gravitational force express itself without its mass representation? "The real possibilities and happenings" in the universe, this force, like others, comes with a package, rules, mass, and probably they would not express themselves without these packages. Yes we are ignoring other elements in order to understand gravity, and "when all other influences are ignored", two black holes would end each other's unique characteristics and become one. Why? Because gravity is the only force that pull, while others have opposite of their forces. But nowhere in the universe gravity behaves so freely to collapse all matter and make one single entity. Gravitational force is manipulated:

A) either by other unknown forces such as the ones the that can expand the universe.
B) or by the collection of different sizes and relations between gravitational bodies.

If we choose (A), we must find out what these forces are, and how they interact with gravity. If we choose (B), we must make sure that we know every possible situation that can be created by gravitational bodies in order to make an absolute statement. If we find correct statements in both (A) and (B), we can expect any kind of possibilities; mergings and separations.

You came to the point to accept the fact that there are "not merging" black holes in the universe, and now trying to enrich your original statement with extra forces. Let us know them as long as they are in this universe.

 

How about the gravitational attraction of the rest of the stuff in the universe?

Correct, because gravity doesn't fade away, it merely gets weaker.
So if there's nothing else at all but two black holes they will eventually come together and merge.

Exactly.
In the real universe there are other bodies that exert gravity on our two black holes and that may prevent them meeting.

That's being done.

That's impossible.

Wrong: I have never disputed that black holes in the real universe may not meet. But that wasn't the OP.
If the OP meant in this universe then the answer depends upon far too many factors to give any definitive statement.

 

OP did not ask for something out of this universe either. You take the one side of reality, you isolated all other factors, including

Then you can make concrete assumptions on your isolated universe. "What would happen if two gravitational singularities meet?", you should have said, "there is no such a possibility, because there are other factors". Or, "one possibility is their merger" among others. No, you did not do that, instead, you ignored all "real universe" conditions to support your claim. Blame the language of OP, blame other forces, judge my physics knowledge. Why don't you blame twin galaxies for a difference...

 

Make your mind up.
You previously stated

But I stipulated "no other factors".

You really are dense aren't you?
I have stated categorically that given no other factors then a single black hole would result.
I have also stated that if the scenario is set in the real universe then other conditions would have to be specified and the result may prove to be incalculable.

Let's take it at its simplest: the thread title is -
"What would happen if if two gravitational singularities meet?"
Given that "meet" has a particular meaning in science and engineering (i.e. contact) then the answer can only be: they would merge into one.

As for the rest of your back-pedalling, I've already covered it, and dismissed your "repulsion".

 

You dismissed repulsion with what? With gravity.
How do you explain non-merging twin galaxies? With gravity.
Why things are collapsing into a black hole? Because of gravity.
How do some black holes form different combinations? Because of gravity.

I can do that. If this is what you call special meaning of meeting two astrophysical bodies in science and engineering jargon...

 

And your "point" would be?
I dismissed repulsion because the electrical charge repulsion is nowhere near strong enough not a factor, and the spin repulsion is simply an unproven possibility. But you didn't bother to read your own "sources" did you?

Apart from the italicised one, which of the definitions above would apply to black holes?
No 5 could: and we've been through that, but that sort of meet would be expressed as something like "encounter".