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Do Solo Black Holes Roam the Universe?
sciencehabit writes "Two mysterious bright spots in a disheveled, distant galaxy suggest that astronomers have found the best evidence yet for a supermassive black hole being shoved out of its home. If confirmed, the finding would verify Einstein's theory of general relativity in a region of intense gravity not previously tested. The results would also suggest that some giant black holes roam the universe as invisible free floaters, flung from the galaxies in which they coalesced. Although loner black holes may be an entity that has to be reckoned with, they would still be rare."
Ease off. That was a huge step up from our normal First Posts.
Violence is like duct tape. If it doesn't solve the problem, you didn't use enough.
I find it fascinating that theories developed in the first half of the last century continue to stand up to observation. This fits the predictions of general relativity, and that is almost as exciting as if they discovered something that totally blew away the predictions. The latter would mean we go back to the cutting board, but this is, as I said, almost as exciting. It makes me wonder how much of the 'missing mass' that we lump into the dark matter bucket is actually contained in bodies like this; bodies so massive that we can barely fathom their 'size'.
No... the stars in a galaxy are orbiting their own collective center of gravity, not the blackhole. It just so happens that this collective center of gravity often attracts enough stars that it collapses into a super massive black hole. The most likely scenario for the blackhole to lose it's galaxy is in a collision with another galaxy (although "Collision" is a bad word since nothing actually hits anything else) The center of mass of the 2 combined galaxies would radically change rather suddenly (in galactic terms) and the Super massive blackhole would begin orbiting the new center of gravity. If it's orbit is too far out, it would get flung off. In most situations stars would get flung out with it. But rarely it could shoot off on it's own.
If you were to take the 3 million solar mass black hole in the center of the Milky Way, and plop it into the solar system where the sun is, the Schwartzchild radius would be well within the orbit of Mercury. We wouldn't lose a single planet, though an earth "year" would shrink to roughly 2 hours. Hold your fist at arm's length. That's how big it would appear in the sky.
Now imagine trying to see something like that, from 4 billion light years away, moving faster than galactic escape velocity. The only reason you can see it at *all* is that it's still siphoning galactic gas into its accretion disk. Once it hits intergalactic space, you'll never see it again.
Three million solar masses sounds huge, but is a microscopic fraction of the Milky Way's total mass (1-4 trillion solar masses). Given the quantity of matter orbiting near the center of a galaxy, I'd believe it likely that even if the central black hole were ejected, a new one would form in short (cosmologically speaking) time. So core ejection may not be a one-off, but a common event during galaxy collisions. In which case, there might be enough of them to partly explain dark matter (though certainly not enough to explain it all).
We also know there is a relationship between the mass of the central black hole, and the "tightness" of the arms in a spiral galaxy. But how would core ejection affect this? Given the speed of light, the outer regions of a galaxy would be tightly wound, while the inner region would be loosely wound (after core ejection). Wouldn't that look an awful lot like a barred spiral?
So many interesting questions, so few answers...
Honest Question here - do you really believe that the best way to foster free and open discussion is to severely limit the people that can participate?
Look at my number. It is huge. Yes, I contribute some bullshit every now and then, but I honestly try my best to contribute to this open forum. Why is my number soooo big? Because I chose to lurk first, learn the dynamics and how to do stuff (technical word there), and then post.
It's like this - you want to ride a roller coaster. So, you go to an amusement park. Then you get pissed about waiting in line with the other idiots. What are your options? (a) Build your own rollercoaster; or (b) quit bitching about the line and enjoy the pleasant conversations that do happen, when they happen.
If you are not the owner of a website, who are you to limit, or suggest a limit for that matter, on who can contribute?
Why do I love the internet, and online forums and discussion boards? Because I can hear a...n...y...t...h...i...n...g... on them. If I wanted to have a closed discussion on a topic, I'd go back to yelling at my television. It feels just as good, and is as one-sided as you make it.
In other words, sir or ma'am, I understand that you believe that there were glory days on this site. I'm sure there were. But, limiting who can speak, simply based on how old s/he is comes off as, in my opinion, utter bullshit.
In other words. Learn to ignore the shit. Look for the good. It's there, if you care to be positive. OR, instead of limiting who can post, have a system where you can register your account, but can not contribute until you reach a certain time on the site, or number of articles read paired with time spent reading, or something. I don't know, just quit complaining about it. It's just as annoying as the bullshit posts from user numbers>1,000,000, and contributes nothing to the discussion.
But that is all my opinion. Thank you.
The theoretical evaporation of black holes is an incredibly slow process; a black hole the mass of the sun would only evaporate after some 10^67 years. which considering the age of the universe is 13x10^9 years (or about 6000 if you're a creationist) means it won't disappear any time soon.
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
You obviously don't understand that 10^30 is nowhere near 1/2 of 10^52. It's practically nonexistent on that scale.
"Educate the mind but never at the expense of the soul."~Blessed Basil Moreau
It was actually shortly after I joined that I started noticing the downward spiral in comments.
So it was YOU?!