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What Came First, Black Holes Or Galaxies?
StartsWithABang (3485481) writes "It was one of the most hotly contested questions for decades: we first expected and then found supermassive black holes at the centers of practically all large galaxies. But how did they get there? In particular, you could imagine it happening either way: either there was this top-down scenario, where large-scale structures formed first and fragmented into galaxies, forming black holes at their centers afterwards, or a bottom-up scenario, where small-scale structures dominate at the beginning, and larger ones only form later from the merger of these earlier, little ones. As it turns out, both of these play a role in our Universe, but as far as the question of what came first, black holes or galaxies, only one answer is right."
Chuck Norris
So the best answer we have is that the seeds of supermassive black holes and the seeds of galaxies were what formed first, and they did so at approximately the same time. But these black holes began as quite large structures, growing to at least many thousands of solar masses before the environments in which they were housed could ever be considered galaxies, and so it appears that black holes came first, but they form in regions that will merge-and-grow into large, rich galaxies in very short order.
The article has a pretty in-depth explanation (from what my layman's eyes can see) though.
medium.com unreadable fluff. Please find a better website to spam. Not all of us have tablets, you know.
There need to be supermassive stars . Like this one which is 265 solar masses ! . Chandrashekars limit tells us that a star will collapse into a black hole at >= 5 solar masses . I somehow always imagined supermassive giants collapsing into black holes and galaxies forming around them . The question is is ther only one supermassive star in a galaxy ? or per galaxy? . What if another massive star in a galaxy goes supernova and collapses. will it disturb the gravitational balance?
I read somewhere that the heavens and the Earth came first.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
you are clearly no expert in gravitational physics or astrophysics.
Not black holes, nor galaxies, but da chicken came first.
Tat Tvam Asi
And Anonymous Coward trolls are the worse kind of troll. Moron.
So how did the supermassive black holes get formed?
But what if a galaxy formed, then after a few billion years collapsed entirely into the central black hole, which then caused a new galaxy,...
(leading vaguely to a Yo Dawg meme here)
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
Is this not too dissimilar to how we think the solar system started, the sun first and then the planets?
Esra Erimez
Why is the answer always assumed to be binary? Both processes could have been occuring simultaneously.
"Consensus" in science is _always_ a political construct.
Speaking of why Medium.com sucks...
Why do stories on sites like Medium.com scroll so badly? Jerky, screen tearing...who would want this?
Personally, I avoid sites like this. It is a trivial matter to type some of the article text into Google and find a different web site.
But back to my question...Is it because of the mega large graphics/background? Can I just block that in some way? In Opera?
Of course black holes.
Then galaxies.
But super-massive black holes - the interesting question - probably came last, although they avoided that aspect of the question.
"expected" is sure not how I remember it, and in fact I think this has the historical record backwards. Quasars were definitely a surprise, and the Super Massive Black hole (SMB) interpretation of quasars took a while (a decade at least) to catch on, and the consensus that most galaxies have a central SMB came after that, after some local galaxies (such as our own) showed signs of having a SMB too. Before all of this most astronomers weren't interested in black holes and even the small number of General Relativity types (such as Zeldovich) who were, and who were looking them, were looking for stellar mass sized black holes, not the SMB variety.
All in all, I think it would be more accurate to say that the SMB-galaxy connection was forced upon astronomers by the data, rather than that they expected it.
Shitty article and the answer is simple.
neither is dr. neil degrasse tyson, but he has a popular science show
Having read the article, I think that "With a Bang" sort of waffled on this. It is hard to see how SuperMassive Black holes (SMB) form in the time available for them to form. (There is a large literature on this, but basically there are problems of the seeds - are the seeds Pop III stars, or something more exotic - and time - how can the mass move around enough to form SMB by z ~ 6?).
I don't really feel you can safely answer the "which came first" question until you know how the SMB actually formed.
A one hour video lecture, Supermassive Black Holes and the Problem of Galaxy Formation, might be interesting to people interested in these problems, but it deals with the galaxy problem more than the SMB problem.
Galaxies, because every blackhole that we've observed is at the center of some galaxy; we've never observed a blackhole just floating around in space. Although, I'd imagine that since blackholes are the result of super massive stars, they could come prior to galaxies if there where large enough stars.
Blackholes have been here since day one. They are simply matter that came from our neighboring universes. They follow different quantum laws than the matter in our universe. Our universe is a stream and it is flowing in one direction. The big bang is only an allusion. If the Andromeda galaxy was moving away from us, we would see that the universe was shrinking instead of expanding.
Except for the part where he is an astrophysicist.
then wouldn't it have sucked in everything that tried to form around it, meaning no galaxy could form around it?
God.
-- I fear explanations explanatory of things explained.
Totally. Aside from the PhD in astrophysics from Columbia, he hardly knows any astrophysics.
Sub: Perception and Vision-Cause and Effect
The psychology of black-hole every where hides the truth. How can astronomy can catch-up with Cosmology Studies and Energy distribution?
The origins specify Cosmic function of the universe.Cause and Effect- visible-invisible matrix.Search Cosmology Vedas interlinks-
What brought out the cranks today?
Anyone who can claim that General Relativity is wrong has not understood it. It is incomplete, but it is not wrong, and certainly not to the point where black holes would be 'disallowed'. We're pretty good so far at determining what fundamental forces operate in the universe, and there simply is no property of matter which would prevent it from reaching the densities required for black hole formation. We have observed extremely massive dense objects far exceeding that threshold. Whether or not singularities exist in some sort of real way is another question. The internal structure of black holes is also fairly academic. That black holes exist is, as has been said, a direct consequence of General Relativity, which has been shown to be an extremely accurate description of the geometry of the universe, at all scales we have been able to observe, from the sub-atomic to the intergalactic. In order for black holes (or a phenomenon with identical properties) not to exist, you have to both explain the observation of these dense, massive objects, and simultaneously describe why objects cannot be that dense, or more precisely why spacetime cannot be curved such that it forms an event horizon.
ACs: if you do not have a working knowledge of relativity then please don't trouble yourselves to respond to this comment. Your theory has to have greater explanatory power if you want to replace relativity, and if you don't know what it says, well, you're not likely to have a useful opinion on the matter.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.