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New Research Reveals Hundreds of Undiscovered Black Holes (phys.org)
An anonymous reader quotes a report from Phys.Org: New research by the University of Surrey published in the journal Monthly Notices of the Royal Astronomical Society has shone light on a globular cluster of stars that could host several hundred black holes, a phenomenon that until recently was thought impossible. Globular clusters are spherical collections of stars which orbit around a galactic center such as our Milky-way galaxy. Using advanced computer simulations, the team at the University of Surrey were able to see the un-see-able by mapping a globular cluster known as NGC 6101, from which the existence of black holes within the system was deduced. These black holes are a few times larger than the Sun, and form in the gravitational collapse of massive stars at the end of their lives. It was previously thought that these black holes would almost all be expelled from their parent cluster due to the effects of supernova explosion, during the death of a star. It is only as recently as 2013 that astrophysicists found individual black holes in globular clusters via rare phenomena in which a companion star donates material to the black hole. This work, which was supported by the European Research Council (ERC), has shown that in NGC 6101 there could be several hundred black holes, overturning old theories as to how black holes form.
Dark matter always sounded like a hack for me
I'm not one to actually RTFA, but I would at least like the option of doing so before proceeding to argue with other armchair physicists in the comments section.
hundreds of black holes all at once? or is it just grit on the scanner scope?
Why would those supernova explosion have any effect on a black hole, but only give it something to incorporate while the resistance is futile? Black holes don't usually solar sail like it's Hampton's 1999 all over again.
Tha'ts Milky Way, no fucking hyphen.
http://arxiv.org/abs/1609.0172...
I'll have to see them to believe this.
Grit does not emit x ray on a constant basis. And it did, then it would isotropically do it , so we would see black hole everywhere no matter the orientation of our observation instrument ;).
C. Sagan : A demon haunted world:
http://www.amazon.com/gp/product/0345409469/
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This relates to a prediction made by the transcension hypothesis.. or the first really good answer I've heard to the "Where is everybody?" question.
http://brighterbrains.org/articles/entry/the-transcension-hypothesis-an-intriguing-answer-to-the-fermi-paradox
From the article
"This research is exciting as we were able to theoretically observe the spectacle of an entire population of black holes using computer simulations. The results show that globular clusters like NGC 6101, which were always considered boring are in fact the most interesting ones, possibly each harbouring hundreds of black holes. This will help us to find more black holes in other globular clusters in the Universe. " concluded Peuten.
Therefore still undiscovered, as this was just a simulation that provided an explanation of the makeup of the specific cluster under examination - when they added black holes to the simulation, the results matched what the actual cluster looks like while without black holes it didn't
Ha ha ha scientists ha ha ha. :)
Did they detect the one in my wallet?
This is definitely very cool, but "reveals" is a strong word. They've demonstrated that it's a plausible explanation for the puzzling distribution of stars in this cluster, but there are still other explanations that have not been ruled out.
What's puzzling about the cluster is that the stars appear well-mixed -- the high mass stars follow the same distribution as the lower mass stars. That's weird because globular clusters should undergo mass segregation, where the high mass stars slowly congregate towards the center while the lower-mass stars migrate towards the outside (interestingly, this is because self-gravitating systems have negative heat capacity, which is a concept that tends to freak out non-astronomers). And we indeed see that most clusters are mass-segregated.
So why do black holes help? They form from the most massive stars, which died early, and they end up being significantly more massive than the lower-mass stars that are left. So if there are lots of black holes, then the effect of mass segregation is to make the *black holes* congregate towards the center. In other words, mass segregation is still happening, but it's operating on black holes (which we can't see, so we don't notice its effect) instead of stars (which we can see).
There are other ways you can explain this, though. If there's a massive-enough intermediate-mass black hole at the cluster center, that makes the process of mass segregation take longer, so it might not have had time to make any significant change. A sufficiently large fraction of binary stars within the cluster could have a similar effect (i.e. make the mass segregation timescale much longer). Or, more speculatively, you could posit that there was some dynamical event that happened to the cluster since its formation that mixed the stars, so mass segregation has not had as long to operate as we assume. So their explanation is a plausible interesting one that they have demonstrated can indeed cause the desired effect, which is really cool! But these other options also need to be investigated.
This is all nonsense. There's no such thing as clusters of black holes. These "scientists" have fiddled the data so they can continue to ride on the publicly-funded gravy train, sloshing around in their gold-plated gravy tankers like greedy SJW nerd-whales and waving their grant applications while they laugh in the face of scripture.
Some novae occur though a gentle accretion process, such as a burnt out star with a companion, and some occur through expending all of thier fuel and the lack of thermal pressure causes collapse. Rarely one can be created through a merger of two stars but it's not exactly the same thing. In the first two cases it's not very clear what causes this but there is some evidence the process is not always symmetrical. A supernova often expends as much energy over a few hours to days as the star previously expended in its lifetime. Much of the material is blown off at up to 10% light speed. With the release of so much energy, even a very small deviation from being spherical can provide enough velocity on the black hole to exceed the pull of the gravity in these small globular clusters. So the result of the simulation is interesting and points the way forward for follow up observation.
Is this a possible explanation for the missing "dark matter"?
It's a damn blackhole.
The entirety of the energy would be absorbed.
Who the hell suggested such a stupid idea?
It is like suggesting you could overload a plughole by dropping an ocean on it, when said plughole increases relative to the amount of water that touches it.
The only known thing to influence blackholes is gravity. (in terms of actually moving the thing)
So the matter that only interacts with other stuff though it's gravity(dark matter), is things that only interact with things though their gravity wells(Black holes). Who would have thought that.
Oh you meant heavier ...
No, for a number of reasons. Dark matter is known to be non-baryonic, it does not interact with normal matter except through gravity and possibly the weak force. Also, the amount of 'missing' mass amounts to some 27% of the total mass in the universe, and finding a few more black holes in a single cluster is, well, completely irrelevant to the topic honestly.
Honestly, that you could ask the question means that you have not actually bothered to read about any of the evidence for dark matter. There are at least five independent lines of evidence which point to it existing, and no other theories can account for all the observations. We've been trying for years to prove this hypothesis false, and failed. The common explanation for the observations (which won't go away if you don't happen to like them) is called dark matter.
Right now we're in approximately the same position as ancient astronomers trying to track the positions of the "wandering stars". They did not know what they were or why they moved, or how to predict their movements, but they seemed to be closer to us than the fixed stars. The heliocentric cosmology that we know today was considered stark raving madness, and heretical to boot. It took until Newton before the theory was established on firm mathematical principles, and even then he could not explain what gravity actually was. Either you're going to have to be content with an incomplete understanding of the universe or you're best off ignoring science entirely. If you choose the latter, however, perhaps you should avoid posting on the topic.
Good!!! What can be seen cannot be unseen, even inside a blackhole!
Would this not instead suggest, previously undiscovered? If they have been discovered, they are not undiscovered.