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Two Supermassive Black Holes About To Embrace
Taco Cowboy writes "NASA's WISE (Wide-field Infrared Survey Explorer) satellite was looking at a distant galaxy, some 3.8 billion light-years away, and saw something rather unusual. At first they thought that they saw a galaxy was forming new stars at a furious rate, but upon closer checking, they found that they were seeing two supermassive black holes spiraling closer and closer to each other. The dance of this black hole duo started out slowly, with the objects circling each other at a distance of about a few thousand light-years. As the black holes continued to spiral in toward each other, they were separated by just a few light-years. Supermassive black holes at the cores of galaxies typically shoot out pencil-straight jets, but in this case, the jet showed a zig-zag pattern. According to the scientists, a second massive black hole could, in essence, be pushing its weight around to change the shape of the other black hole's jet. Visible-light spectral data from the Gemini South telescope in Chile showed similar signs of abnormalities, thought to be the result of one black hole causing disk material surrounding the other black hole to clump. Together, these and other signs point to what is probably a fairly close-knit set of circling black holes, though the scientists can't say for sure how much distance separates them."
Happened over two billion years ago and we're just hearing about it now!? Typical.
So.. if they observed these black holes at a few thousand light years apart, and then some time later (assuming less than a few thousand years later) at just a few light years apart... does this mean that they are moving toward each other at faster than the speed of light?
Two Supermassive Black Holes About To Embrace
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Given the countless galaxies, each with its own supermassive black hole, just like intersecting waves, the gravitational waves could theoretically act like waves in the electromagnetic spectrum, or classical physics experiments with waves. Some waves would cancel, others would be much larger than the 2 source standing waves, and thus would appear as a stronger signal to a gravitational wave detector, given said detector was sensitive enough.
Gravitational waves could also bring us closer to the point in time of the "big bang" than the cosmic microwave background radiation images. I sincerely hope this discovery, gives solid reason to develop said gravitational wave detector. Kudo's to the NASA WISE team!
They're looking at the wavy motion in the jet they put out - which is apparently showing a history of their interaction.
Did it really? I think that's a philosophical question. Personally, I think not only space and time but also cause and effect are relative to the spectator.
The light carrying the information that this is happening is just arriving here. The speed of light is also by definition the fastest information can travel. It may "in reality" have happened 3.8b years ago, but the effect can only now affect someone here. Even if you happened to have an observation post there and 3.8b years ago they noticed "hey, they're falling into each other NOW", and they sent that information right away, the information would not have reached us before the event since, well, the information of the event ITSELF is traveling at the speed of light, which, as stated before, is the fastest an information sent to us by the observation post could have traveled.
Long story short, the absolute moment in time when something happens does not matter as long as you cannot overcome its information propagation speed. It will of course change if someone happens to find a way to propagate information faster than the speed of light... which would open a completely different can of worms if you ask me (but that's beyond the scope of this post now).
What this all comes down to is that the absolute moment of some event does not matter, but only the relative moment that you receive the information.
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Glaciers melting in the dead of night
And the superstars sucked into the supermassive
Supermassive black hole
You are welcome on my lawn.
You're close - but the whole point of relativity is that there is no "absolute time". With one caveat (see below) It's ALL relative to the observer. There are some observers (specifically those roughly motionless with respect to the earth and the two black holes, like us) for whom "then" and "now" are separated by 3.8b years. There are (or could be) other observers (specifically those traveling at something close to the speed of light in along a line between the black holes and us) for whom the two events are separated by far less time. For someone traveling along that line at the speed of light, the two events would be simultaneous.
The only hard and fast rule is that space-time is divided into 3 zones:
* The absolute past - events within (or on the surface of) the light-cone leading up to here-and-now
* The absolute future - events within (or on the surface of) the light-cone starting at here-and-now
* Everything else - events in neither light cone, which means they cannot affect us and we cannot affect them. Depending on an observer's motion relative to us and such an event, someone might see the event as happening at the same time as the here-and-now, or before, or after. It doesn't matter, because such an event is not causally connected to the here-and-now in either direction.
The interesting thing is that the vast majority of the universe is in the "everything else" zone.... contemplate that one for a while...
Stupid question, but,
If they were 1000 LY's apart, and are now just "a few" LY's apart, *during the timespan of human scientific observation via modern optical tech*, does that indicate they are traveling FTL?
eg, they moved 1000 LY inside of (50?) earth years.
The speed of light is also by definition the fastest information can travel.
No, it's not.
Sorry, Opportunist, it looks like this eloquent and reasoned rebuttal has not only completely defeated your argument but also dealt a death blow to that silly Special Relativity baloney.
..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?
So what happens when both black holes collide and suck each other in?
As you read about black holes and event horizons you'll find that an external observer will never really see anything "hiting" the center of the black hole as time dilation forces the object to appear to go slower and slower as it descends the gravity well of the singularity.
In short, the heat-death of the universe will happen before we (assuming we live forever) ever find out what happens to this kind of singularity merger.
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See it like this:
A black hole (size 0) combines with another black hole (size 0) to form a bigger black hole (size 0). 0+0=0 so that works.
As for location: black holes do have a location. It's at the center of their schwarschild radius.
All this is difficult to know for sure. We can hardly go and take a look.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
Galaxies are travelling away from us faster than the speed of light from them can reach us. Aren't they traveling faster than light? Oh, that's expansion... So, if it's space that's moving then the matter doesn't have to travel through space to achieve faster than light speeds.
That's just the result of a weird (put pragmatically practical) definition of space-time coordinates called "co-moving coordinates".
According to the "normal" rules of special relativity, the speed of light relative to us is the same everywhere, there's no such thing as "space itself expanding", and nothing goes faster than light. However, using those same definitions, we are the oldest part of the universe (using our reference system), all distant galaxies moving away from us at high speed are aging more slowly, everything gets more distance-contracted further out, and at a distance equal to the speed of light times the age of the universe, the big bang is only just beginning and time is standing still. Not just because we have to wait for the light to get here, but "right now", correcting for the travel time of light. It's just a result of relativistic time and distance contractions. Other civilisations out there will use themselves as the reference point and will have a similar view centered around them. In fact, we may say that they don't exist yet while they say we don't exist yet and both are correct from their point of view.
However, since that's not a very practical and certainly not an objective model (no matter how correct it is), cosmologists decided to use a different coordinate system. A meter anywhere in the universe is defined as what's measured by a one meter stick that is moving together with the rest of the expanding universe (undoing distance contraction), and time is defined to be the time indicated by local clocks that are also traveling together with the expanding universe (undoing time contraction). The effect is that with this coordinate system, the universe is nicely homogenous, the same age everywhere, truly infinite, and there's no longer anything special about our location.
The downside is that the speed of light is now relative to the local "expanding space", and this space can exand more quickly than the speed of light. There's nothing physical about this "space", it's just a mathematical artefact resulting from the coordinate system we chose.
Very distant objects that exist "now" in the second model, will never be visible to us because their light is trying to get to us on a kind of cosmic conveyor belt moving the other way more rapidly. In the first model, those objects don't exist yet and never will because local time has slowed down to an asymptotic halt. The definition of "now" is just "the collection of events that we happen to have assigned the same time coordinate to", and this depends entirely on the choice of coordinates. There's no such thing as an objective "now". But no matter what coordinates you use, we all agree that we will never see those objects.
Both point of view are "correct", we are just measuring things a bit differently but all conclusions are the same. And no matter what model you use, nothing can ever overtake an actual photon in vacuum. Something at a distance may move faster than a photon here, but that just depends on how we define "time", "distance" and "speed". Nothing actually goes faster than a ray of light at the same location.
Well, time does slow down in the vicinity of a black hole, so they may still be "just about" to embrace, and forever will be from our point of view. Depending on what coordinate system you use, of course.
We can never actually see something cross the event horizon of a black hole, objects will always slow down to a halt before the event horizon (even though from the point of view of the object itself, time continues normally and it crosses the boundary in a finite amount of time). I expect the same is true for black holes collapsing into each other. The whole thing will just appear to freeze.
Actually, it's the other way around. From their point of view, they will embrace just fine. From our point of view, they never will.
If you fall into a black hole, outside observers will see you slowing down to a halt, and your watch stopping, before you reach the event horizon. For you, though, time will continue normally and you will cross the event horizon in a finite amount of time.
In fact, depending on what coordinate system you use, black holes may not even exist yet. Every "almost-black-hole" is stuck in time at the stage just before the last bit of matter falls in to make it an actual black hole. But since coordinate systems are inherently subjective, that doesn't really matter.
Are you suggesting, perhaps, that Stupid travels faster than light? You may have a point.
It's not by definition the fastest information can travel. It's the fastest according to our current understanding, which might be wrong.. The OP confused a priori with a posteriori truth -- logical certainty with scientific confidence.
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I've never been able to wrap my brain around it, probably because of the aforementioned "absolutist" mindset.
I can see how an event being outside of any real sphere of effect makes it irrelevant to us for 3.8 billion years, but saying it didn't happen until it's been observed happening just sounds like an internet troll to me.