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Center of the Milky Way Has Thousands of Black Holes, Study Shows (npr.org)
New submitter xonen shares a report from NPR: For decades, scientists have thought that black holes should sink to the center of galaxies and accumulate there. But scientists had no proof that these exotic objects had actually gathered together in the center of the Milky Way. Isolated black holes are almost impossible to detect, but black holes that have a companion -- an orbiting star -- interact with that star in ways that allow the pair to be spotted by telltale X-ray emissions. The team searched for those signals in a region stretching about three light-years out from our galaxy's central supermassive black hole. What they found there: a dozen black holes paired up with stars. Finding so many in such a small region is significant, because until now scientists have found evidence of only about five dozen black holes throughout the entire galaxy. What they've found should help theorists make better predictions about how many cosmic smashups might occur and generate detectable gravitational waves. The study has been published in the journal Nature.
That sucks.
And it's the best hole
This is a very interesting result since it may have implications for Dark Matter. There is a gamma ray 'haze' around the central core of the galaxy that has caused some interest because without what used to be thought of as an unfeasibly large number of pulsars it would be impossible to produce from known astrophysical and so the thought was that it could be due to Dark Matter annihilations. However, if there is a far higher population of BHs than originally thought presumably this also means there should be a lot more pulsars and, if so, then this haze could be just from all these pulsars.
This galaxy really sucks!
It's nice to confirm that these exist, because that means that we'll get to listen to extreme mass ratio inspirals as they fall into the central supermassive black hole. It produces a strong gravitational signal that's audible for a very long time, allowing high-precision tests of general relativity.
You know, I told my precious star to stop hanging out with those no good singularity but did she listen? NOOOooo. She said, "he's just in my orbit" but then was consumed by him talking about "singularity this" and "singularity that" all the time. Before you know it you walk in on her are kissing that beatnik's event horizon, she goes critical and now is just like that jerk! That's when she starts merging with him in public for everyone to see! I know she has always had a warped perspective of time and space but this is on a whole new level!
Parents, you've been warned! ;)
Anons need not reply. Questions end with a question mark.
...that carries weight.
Zuck's first thought on learning this. I guarantee it.
The black holes don't exist.
All this is a chinese tale.
Black Holes supposedly suck in everything --- will it drag the dark matter in, as well?
To remind you that the Earth is only 6000 years old.
Also it's flat. Every day the Sun God Ra rides across the sky in his chariot.
This notion you have that the universe is 14B years old and that there are black holes at the centers of galaxies is a nice story.
But it's just a story.
Oops. I'm late. Time to go take my meds.
The Sea of Holes.
Excellent! And actually not very surprising. It explains why our galaxy rotates and just not get sucked into a singularity.
Cool
Center of the Milky Way has thousands of black holes?
So does Chicago!
Of course! That's where we keep them!
Black holes matter - so does non dark matter
I was having troubles seeing how this could work. Unless you are very close indeed, a 5 solar mass black hole interacts with other stars in exactly the same way as a 5 solar mass star, as the only force in action is gravity. So how can these stellar mass black holes gather near the galactic core?
The first sentence of the paper is: "The existence of a ‘density cusp’—a localized increase in number—of stellar-mass black holes near a supermassive black hole is a fundamental prediction of galactic stellar dynamics".
I looked up the reference for this (Bahcall and Wolf, http://adsabs.harvard.edu/doi/...). It is late at night and decades since I studied stuff like this, so mostly I'm going on that paper's abstract plus a bit of background knowledge.
The important assumption of Bahcall and Wolf is that the stars are much less massive than the small black holes (SBH), which are much less massive than the galactic black hole (GBH). (My error was in not considering this.) Now when you have a mixture of stars and SBHs near the GBH, they are zipping around and sometimes have close encounters where they gravitationally interact. These interactions on average will shift kinetic energy from the higher energy object to the lower energy object. Due to the mass difference, this means in a SBH/star interaction, the SBH will (more often than not) transfer energy to the star, so it will slow and fall deeper into the gravitational well of the GBH.
A good analogy is a gas with heavy and light molecules. The heavy molecules will move more slowly and at the bottom of the container the gas will be richer in heavy molecules compared to at the top of the container.
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
I know their orbit must be stable, but I'm wondering why it stay that stable.
Couldn't one of the black hole suck something big one time, gain a lot of gravity pull of collapse the whole thing?
Elok
I have looked through glass crystals and through small diamonds. It will show many dozen windows, but I know there is only one real window in that room, and all but one of them are ghosts created by the facets of the crystals or the diamond.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
The reason "science" is losing it's credibility is really stupid people, who don't understand "science," and who prefer to be intentionally stupid and not learn, keep making posts like yours. Or rather, it's why "science" is losing credibility with really stupid people.
https://www.youtube.com/watch?...
https://www.youtube.com/watch?...
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
Shouldn't it be more? What is the percentage of stars that produce a black hole at their deaths? Shouldn't our galaxy have thousands and thousands (or more) out of billions of star deaths?
Tired of my customary (Score:1)
Vaccines cause autism, sterility, and priapism! Huzzah! Baginza!
And what is nougat anyway?