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Astronomers Discover 33 Pairs of Waltzing Black Holes
Astronomers from UC Berkeley have identified 33 pairs of waltzing black holes, closing the gap somewhat between the observed population of super-massive black hole pairs and what had been predicted by theory. "Astronomical observations have shown that 1) nearly every galaxy has a central super-massive black hole (with a mass of a million to a billion times the mass of the Sun), and 2) galaxies commonly collide and merge to form new, more massive galaxies. As a consequence of these two observations, a merger between two galaxies should bring two super-massive black holes to the new, more massive galaxy formed from the merger. The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars. The result is a black hole dance, choreographed by Newton himself. Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy."
Apparently, the definition "waltzing"/a waltz has been diminished to the extent that now it just refers to two objects moving together. Hum.
I guess I'm just a cranky music theory lover though.
Who leads and who follows?
http://en.wikipedia.org/wiki/First_Amendment_to_the_United_States_Constitution
the Y3B bug already being dismissed as irrelevant
At those masses, the choreographer is most likely Einstein (nvm that dark matter might be not the underlying cause of some discrepancy between how we think gravity works and what we are observing at galactic scales; we might as well have a different choreographer yet)
One that hath name thou can not otter
Wake me up when they've found some doing the Foxtrot or the Lindy Hop.
"[...] a merger between two galaxies should bring two super-massive black holes to the new, more massive galaxy formed from the merger. The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars. The result is a black hole dance, choreographed by Newton himself. Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy."
Don't worry - I'm sure Russia will have an ill-defined plan to divert this somehow. By then.
(Sorry, couldn't resist.)
be square dancing?
... is the only "Dancing with the Stars" I'd ever want to see.
Finally I can post this link and not be offtopic:
http://www.youtube.com/watch?v=Cg1dMpu4v7M
Knowledge is power. Knowledge shared is power lost.
choreographed by Newton himself.
He might try, but the accurate calculation of black hole orbits requires the complete infrastructure of General Relativity, so Einstein is calling this tune.
Wow, when I was in university, Black Holes were still a mostly theoretical idea and we had no real empirical evidence to support their existence.
Now we've got 33 pairs of them entwined in death spirals, and we're pretty sure every galaxy has one.
There's still a lot out there that we can't even conceive of ... I can't wait to see what the next 15-20 years brings us. I like the fact that the universe is vastly more complicated than we've ever really been able to guess at.
Cheers
Lost at C:>. Found at C.
Great, the collision of these things is exactly the kind of event we need for detecting gravitational waves. These kind of 'inspirals' emit very distinct pattern, which can be retrieved very efficiently from the noise with matched filter banks. The higher the mass, the lower the frequency of this 'chirped' signal, so it is probable that these colliding super-massive black-holes cannot be detected with the ground-based kilometer long observatories, which are measuring right now. This is probably more something for the space-based LISA mission, which can probe much lower frequencies since it has a base-line of millions of kilometers.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Given that it's pretty common knowledge that a) galaxies have big black holes at their centers and b) that galaxies collide... is it really a discovery that black holes will orbit one another as their gravity catches hold of one another?
I mean okay, it's cool to actually have proof of it but I am pretty sure I read about orbiting black holes a while back already. Not to take the icing off the cake here, I am probably more annoyed with the slashdot heading.
Moved to http://soylentnews.org/. You are invited to join us too!
So if a single magnestar can produce a truly massive gamma ray blast just by displacing its crust by a couple of centimeters http://science.slashdot.org/story/09/12/27/1639207/Fifth-Anniversary-of-a-Cosmic-Onslaught, what happens when two super-massive black holes finally merge?
Funny how everybody is always talking about all those black holes in the universe while, in fact, none currently exist. Sure, there are objects that are very, very close to becoming a black hole, and for all practical intents and purposes they can be pretty much considered as such, but in our reference frame it will still take an infinite amount of time before that last bit of matter falling in makes it an actual black hole, with event horizon and all. That's because the intense field of gravity slows down time to an asymptotic halt, so the approaching last bit of matter required for the true black hole will pretty much stop before it gets far enough (from our point of view). The only person who will ever be able to say that black holes exist, is someone who is actually falling into one (which, from an outside observer's point of view, would take an infinite amount of time even though the person himself will experience the event in finite time).
As with so much of science: if you went out there and didn't find it, that would be much bigger news, because it would cast doubt on your present theory.
Confirmation is never as exciting as falsification, but it's good that science isn't all that exciting, or nothing would ever get done. The more confirmations you get, the further you can speculate, with the chance of getting something that can be falsified.
But most of all, explain what causes the observed effects of hypothetical "dark matter" and "dark energy". My young children are smart enough to know that the dark matter story sounds like total and utter bull. The story goes like this: "We see something that looks like it causes things to move, but we don't know what it is, and we can't see it, or measure it, create it, or understand it at all. These unobservable matter blobs (and energy) may be 95% of everything we observe! We see something we can't explain, so we're calling it 'dark matter' and moving on with the old story that has worked for a while and still gets us grant funding." Why no one with a brain is calling out this story for its absurdity is astounding.
Because people with brains -- or at least those with brains and a bit of particle physics knowledge -- know that the idea of a type of matter that has mass but does not interact electromagnetically and is thus extremely hard to detect is not that outlandish. We already know of one such particle, the neutrino. A more massive neutrino-like particle is a prime candidate for dark matter, and is predicted by theory outside of dark matter. And while it's still highly speculative, there are teams out there right now who believe they are on the trail of detecting this particle.
In other words, they are doing exactly what you think they should be doing, and working on the problem. But surprisingly, doing actual useful work in this area requires more education than your children, or you for that matter, possess. Sorry!
The most dangerous hubris in science is the refusal to accept that we're far more ignorant about our physical environment than most would like to admit.
Stand in front of a mirror, look yourself directly in the eye, and say that fifty times.
All the things you point out, like what dark matter actually is, are holes in physics knowledge that physicists readily admit too. At least to the extent that you accurately describe the holes, rather than your gut feeling about what sounds too weird to be true. So who is showing hubris again?
The enemies of Democracy are
You do understand that science is a process right? We're in the process of figuring all of that stuff out. How else would you even know to ask those particular questions?
Your young children can be led to believe that Santa Claus and Easter Bunny exist, so I wouldn't exactly take their word for it on something like dark matter. The reason it's called 'dark matter' is because we don't know WTF it is. People are trying to figure that out. It's not as if they moved on, and decided to just not research it...
For the holidays, isn't it. If they only did it before Christmas...
Well, as it's theorized the Milkyway has already swallowed others (reference missing), there should either be multiple black holes in our galaxy, or this provides a good estimation of how long it's been since that happened -- according to Einstein, of course.
âoeThe wall between art and engineering exists only in our minds.â -- Theo Jansen
They shouldn't shows us a Higgs Boson particle as it would seal our fate as a "Type 13" civilization when our planet collapses into something the size of a pea due to experiments designed to find the mass of t6he Higg Boson Particle.
Tsukasa: All I really want, is to be left alone...
Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy.
I'll believe that when I see it...
You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
3 billion years for a species to not kill itself long enough to escape this galaxy, lest all life on it perish?
1) nearly every galaxy has a central super-massive black hole 2) galaxies commonly collide and merge to form new, more massive galaxies. [...] The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars.
If this was a comment on the life of corporations, I would mod it "Insightful" (just substitue "galaxy" with "corporation" and "back hole" with "CEO").
Just goes to show you, micro and macro-scale ecology is eeringly similar. I think we need a lecture on fractals and how they apply to this situation.
Very very long indeed. I understand the timescales in TFA are in million to billion years, so the frequencies photonic expects to detect would be conversely so low that this'll just be a constant at our timescale... I fear we'll not see a turn ;-)
Herve S.
When the galaxies collide , what effect does it have on the inhabiting planets inside that galaxy, or is it something you would not feel, just all of a sudden (like in a crowded gym...) you look up to see twice as many people (or in this case planets and stars) then before?
If your detector is sensitive enough to observe lots of galaxies at the same time, you will be able to observe a few at the final stage of the inspiral. The system looses energy due to gravitational waves, thus the distance between the two objects will decrease and the rotation frequency will increase up to the point that they merge. It is this final stage that we want to detect, which the gravitational waves are sent with higher frequency and intensity.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
I think the terminology used leads to confusion in the layman. "Dark matter" sounds like it's something real, like matter but that's undetectable. In actuality, it's just a placeholder for something unknonwn, like null in a database. It could be undiscovered matter, or it could be an undiscovered property of known matter. By giving it a term, most people end up with the impression that it's the former rather than both.
"If a nation expects to be ignorant and free in a state of civilization, it expects what never was and never will be."
I think the terminology used leads to confusion in the layman. "Dark matter" sounds like it's something real, like matter but that's undetectable. In actuality, it's just a placeholder for something unknonwn, like null in a database.
Well it is in part just a placeholder for something unknown, not the name of some specific kind of matter. On the other hand, the reason it's called "dark matter" is because it is neither emitting nor reflecting enough light for us to see it directly. It is literally dark. And since the indirect gravitational evidence for this matter indicates that there is a ridiculously massive amount of it surrounding various galaxies, this is rather surprising. We can see clouds of hydrogen gas between galaxies, for example, so if this other matter was 'ordinary' we should be able to see it, too.
Thus the leading candidate for dark matter is in fact something that is like normal matter but undetectable by any of our long-range direct detection methods, all of which involve electromagnetism. If it is a type of particle that does not interact electromagnetically then, to the extent that "vision" implies photons, dark matter is literally invisible. And it is extremely hard to detect, unless you count the gravitational evidence in the first place.
So "dark matter" in a way really does give the correct impression to the layman. It's just that the layman, not having heard of a kind of matter that has mass but is invisible to telescopes sounds really weird and crazy. That's fine and dandy, until the layman decides that their lack of knowledge and gut instinct is enough to say that the scientists have no idea what they're talking about.
Of course the matter (heh) isn't fully decided yet or anything. The MACHO vs WIMP debate presses on. But as Hubble and other telescopes continue to fail to find enough objects in the galactic halo to account for dark matter, and with the still highly speculative but very exciting WIMP search showing several candidate events, things are definitely leaning in that direction.
Either way, neutrinos are a predicted and then subsequently observed form of the kind of non-baryonic matter we're talking about. So even if it's not WIMPs that make up the dark matter halo, it isn't a ridiculous idea.
The enemies of Democracy are
Whether you believe he's on to something or completely nuts, at least he's thinking about the paradoxes instead of ignoring them.
Uh... no. His notion of what a paradox is is retarded, and saying that people 'ignore' these paradoxes when they never exist in the first place is also retarded. A couple groaners at brief glance.
"We have the same question with the equation E = mc2. Einstein was nice enough to provide us with this simple equation, but not nice enough to tell us why the energy depends on the square of the speed of light."
Yeah, he never explained it, unless you count the derivation of that equation in his paper on SR.
But even worse, he "proves" the classical kinetic energy equation is wrong thusly:
"The equation is developed from the acceleration, as I just showed. The work-energy theorem requires a change in velocity, which is an acceleration. You cannot get work without a force and you cannot get a force without an acceleration. But the current kinetic energy equation has no change in velocity. A particle has kinetic energy with a constant velocity. If the kinetic energy equation is developed from an acceleration, it means the energy depends on the acceleration. The particle should have kinetic energy only while it is being accelerated."
This is retarded, but quadruply retarded for someone who is claiming their amazing math knowledge is disproving physics.
Yes, the kinetic energy equation is "developed from" the acceleration, in the sense that Work/Energy is an integral of Force. Force defines the rate of change of kinetic energy. His statement that if the force is 0 then the energy should be zero is equivalent to saying that if f(x) = 0, then the integral of f from 0 to x should be zero!
Ugh. Yeah, maybe the OP should read that. He seems to be the kind of guy who would love to hear arguments that the Scientific Establishment has been ignoring obvious paradoxes for hundreds of years that make sense if you know absolutely nothing about the math/science in question.
The enemies of Democracy are