The Universe Has Made Almost All the Stars It Will Ever Make:
But there's a big puzzle here. Exactly what puts a cap on the number of stars the universe has made and will ever make? This question has long been a subject of intense astrophysical debate, particularly in relation to the stellar composition of individual galaxies. For example, our current cosmological paradigm (or at least the one that most scientists subscribe to) is that we live in a universe dominated by dark matter, and in a dark matter universe the biggest galaxies should have formed the most recently,4 being assembled by the hierarchical, gravitationally driven merger of smaller systems. Yet if you examine very large, massive galaxies you find that they tend to be composed of older stars, suggesting that they've already sat around in their dotage for a very long time.
To try to explain this, astronomers invoke the idea of "quenching," where something acts to suppress or shut down the formation of new stars across galaxies. Not surprisingly, you need a pretty potent mechanism to quench anything on these scales, and among the most plausible culprits are the supermassive black holes that exist at the core of most galaxies and which can flood the space around them with photons and particles emitted from material as it screeches toward their event horizons. That outward transfer of energy can, quite literally, blow away the interstellar gas that would otherwise cool and clump into new stars.
The precise details of how this might work are certainly not yet fully understood. But there are new tantalizing clues in the fact that the masses of supermassive black holes appear to correlate with the mass of stars contained in their host galaxies.5 That is pretty shocking because even a supermassive black hole a billion times the mass of our sun only occupies a volume similar to that of our solar system. So somehow a galaxy that spans tens of thousands of light-years is intimately related to what is, in effect, a microscopic dot at its center.
(Score: 2, Flamebait) by Runaway1956 on Thursday August 20 2020, @11:11PM (2 children)
Sitting in the restaurant at the end of the universe, we all looked around, and, no, there were very few young stars. But, what would you expect? Why would anyone create a bunch of new stuff when the universe is dying anyway?
Abortion is the number one killed of children in the United States.
(Score: 1, Informative) by Anonymous Coward on Friday August 21 2020, @12:29AM
Runaway! The Assholephysicist! His knowledge is better than yours!
But anyway, Runaway, are forgetting that Milliway's is a fictional construct, and that stars can create new clouds of dust and gas, that are the makings of new stars. Recent study on the Supernova of Kepler [phys.org] spells this out (and would've been a better sub than this one.) Stuff moving at 20 million miles per hour since 1604. Space is mind-bogglingly big. You may thing down the road to the
chemistWalmart is a long ways, but that is nothing to space.In fact, also, the materials our own solar system was made of, especially the heavier elements like carbon, oxygen, nitrogen and iron, were forged in exploding stars that are now long dead. And usually all it takes is a shock wave, travelling at, say, 20 million miles per hour, to disturb a dust and gas cloud (or, nebula) enough to make it suck, and suck hard enough to start nuclear fussion, at least of the simpler elements.
And don't get me started on galactic collisions.
(Score: 0) by Anonymous Coward on Friday August 21 2020, @03:05AM
Try the Big Bang Burger Bar. Plenty of young star wannabees there, buncha dusty punks.
(Score: 0, Insightful) by Anonymous Coward on Thursday August 20 2020, @11:37PM (5 children)
Who gives a shit anymore? Dark matter is the most obvious wrong idea in science history so anything that assumes dark matter, like this article, is also wrong.
How many hundreds of billions have been spent on looking for evidence of dark matter and there is none? GR makes the wrong predictions, and has since the 1930s. That is all this is.
(Score: 2, Informative) by khallow on Friday August 21 2020, @01:18AM (1 child)
Neutrinos are an obvious counterexample. We've found dark matter with the right sort of characteristics. We just haven't found enough.
We may never find enough dark matter, because it isn't there in the necessary quantity, but it's a far cry from finding none at all.
(Score: 1) by fustakrakich on Friday August 21 2020, @05:24AM
:-) When you travel at or near the speed of light, all that "dark" matter will light up! Bigger than Times Square!
It's a Doppler thing
La politica e i criminali sono la stessa cosa..
(Score: 2) by maxwell demon on Friday August 21 2020, @01:03PM (2 children)
Yeah sure, and all astrophysicists are stupid, and you (probably without any astronomy knowledge beyond popular science articles) can have a better understanding than those people who dedicated their whole lives to studying it.
Of course it may turn out that dark matter is the wrong hypothesis. But if so, your agreement with the facts will only be coincidental.
Actually, while I don't really care one way or another, I do hope that one day dark matter will be proven beyond any doubt just because otherwise all those morons who “knew” that dark matter was wrong without actually having any knowledge beyond some popular science articles they've read will boast themselves with “I told you so”.
Actually I'm convinced that the majority of them would be strong proponents of dark matter if scientists had come to the conclusion that it is a bad model, and favoured another option instead.
Well, you couldn't have illustrated your lack of knowledge better. Here's a hint: Why do you think the most prominent alternative to dark matter is called “Modified Newtonian Dynamics” and not “Modified Einsteinian Dynamics”?
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0) by Anonymous Coward on Sunday August 23 2020, @04:46AM (1 child)
"Yeah sure, and all astrophysicists are stupid, and you (probably without any astronomy knowledge beyond popular science articles) can have a better understanding than those people who dedicated their whole lives to studying it."
While I'm not taking any positions on this (TBH, I don't really know enough about this to take any positions) I generally see appeals to authority as a sign of weakness. Arguments like "you think you know better than the professionals" is not an argument.
If someone has a specific argument to make one way or another then make it. Claims like "they know better because they studied it longer and therefore you lose" is not an argument but a sign of weakness.
(Score: 2) by maxwell demon on Sunday August 23 2020, @03:08PM
You're misunderstanding the concept of “appeal to authority.”
If I had claimed that dark matter is true because the majority of astrophysicists think so, then that would be an appeal to authority.
But that's not what I did. The post I answered to basically claimed that the author knows better than those astrophysicists, and moreover that one has to be pretty stupid to believe what those astrophysicists believe, without giving any evidence that this claim is backed up by any knowledge at all (and indeed, some evidence that there is a distinct lack of knowledge). That is, the poster has not just made a claim about physics (dark matter is wrong) but about the astrophysicists (they have to be pretty stupid to believe that). And that claim I countered, and for that it is not an appeal to authority, because there is lots of evidence for them being knowledgeable and not entirely stupid. That doesn't mean they are always right, but it means their position isn't completely unreasonable.
And yes, “you think you know better than the professionals” is an argument if the one this is aimed to shows no evidence of actually knowing better.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 0, Troll) by EJ on Thursday August 20 2020, @11:41PM (8 children)
Astrophysicists don't know shit. The worst part is they don't even know that they are idiots.
They're looking at a tiny snippet of the universe, and extrapolating nonsense.
(Score: 2, Insightful) by Anonymous Coward on Thursday August 20 2020, @11:49PM (2 children)
If you personally ask them, most will agree a good many current theories may turn out flat wrong. All we have are the best guesses so far. If you have a model that fits observations better, bring it up! Otherwise, stop complaining that we are not omniscience.
(Score: 0) by Anonymous Coward on Thursday August 20 2020, @11:52PM (1 child)
A model that fits the observations better than one with infinite parameters like dark matter does not exist. It is like arguing with someone about whether god exists.
(Score: 1, Touché) by Anonymous Coward on Friday August 21 2020, @12:45AM
Confucius says: If you argue with a jihadi about whether God exists, you will soon learn the answer.
(Score: 2) by Pslytely Psycho on Friday August 21 2020, @07:00AM (4 children)
And your Astrophysicist creds are?????
Alex Jones lawyer inspires new TV series: CSI Moron Division.
(Score: 2) by Bot on Friday August 21 2020, @07:13AM (3 children)
Logically following GP post, "not being an astrophysicist" should be enough cred.
TFA is basically saying that the pretty big bang theory says X but we observed Y so we made up the assumption Z according to whom the as yet unprovable title of the article stems.
OK a little brick of logical knowledge that will be used to develop the theory further. Personally if I had a career there I would pursue less epicyclist stuff but who knows maybe I could not even choose.
Account abandoned.
(Score: 2) by Pslytely Psycho on Saturday August 22 2020, @03:13AM (2 children)
Ah, but there was no logic nor evidence presented. Just a childish rant that attacks without reason and without even the slightest argument supporting objecting to "extrapolating nonsense" with an example of what they consider to be nonsense and why.
Of course in this insane age, I guess name calling like a five year old trying to get attention now counts as a reasoned, logical argument.
A good many theories are unproven and many may sound absurd on their surface, that's kind of the point, you falsify with evidence. At one time the thought of exceeding 25mph (40.2kph) was believed to be fatal, and human spaceflight or a heliocentric solar system a flight of fancy or blasphemy. Evidence is what changed peoples minds. If you have to resort to name calling, then there are only a few possibilities.
a: troll
b: ignorant troll
c: totally fucking ignorant troll
d: compensation for very laughable sexual equipment
e: needs a medication refill
f: needs a hug
g: way over the legal limit to drive
h: is actually five years old
Alex Jones lawyer inspires new TV series: CSI Moron Division.
(Score: 2) by maxwell demon on Saturday August 22 2020, @05:55AM
Of course not. Logic and evidence is what scientists use, and the OP clearly didn't want to give the impression to secretly be a scientist. ;-)
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Bot on Saturday August 22 2020, @03:27PM
You are right in principle except the theory being "therefore there is some undetected AND POTENTIALLY UNDETECTABLE matter which makes the equations great again" is not easily falsifiable.
Account abandoned.
(Score: 2, Interesting) by Anonymous Coward on Friday August 21 2020, @12:17AM
"the biggest galaxies should have formed the most recently ... being assembled by the ... merger of smaller systems."
If bigger galaxies were assembled by the merger of smaller systems wouldn't you expect the bigger galaxies to have older stars than the smaller systems?
"Yet if you examine very large, massive galaxies you find that they tend to be composed of older stars"
Isn't that what we would expect?
I'm sure I'm missing something, can someone explain? Thanks.
(Score: 3, Funny) by fustakrakich on Friday August 21 2020, @12:38AM (10 children)
A galactic microdot... heavy shit, man!
La politica e i criminali sono la stessa cosa..
(Score: 2) by JoeMerchant on Friday August 21 2020, @01:01AM (9 children)
Calling the black hole at the center of a galaxy "microscopic" is like calling the local super-cluster "tiny", a blue whale "featherweight", Betelgeuse "insignificant", etc. It's all a matter of perspective, but anyone who contemplates being in the 0.08C orbit speed neighborhood of a black hole would find it to be anything but negligible.
Україна досі не є частиною Росії Слава Україні🌻 https://news.stanford.edu/2023/02/17/will-russia-ukraine-war-end
(Score: 5, Touché) by Kitsune008 on Friday August 21 2020, @01:43AM (8 children)
Obligatory 'Whooosh!'
Microdots, not Microscopic. There is a huge difference, or a small difference...go ask Alice, when she's ten feet tall.
You apparently cannot see through your Four-way Window-panes, and have missed the Orange Sunshine, through the Purple Haze.
Apologies if English is your is not your first/primary language, but as Jimi Hendrix asked: "Are you experienced? Well I am...", obviously you are not.
(Score: 1) by gmby on Friday August 21 2020, @02:30AM (7 children)
Been there; done that.
Don't recommend it. Times have changed.
If you do choose to be "experienced;" then do it with someone you trust. Had to babysit a dummy from doing stupid things that would have been a dead experience for him and a cop experience for us. Ether way; it was a bad trip for us.
It's very hard to tell the dosage of things bought off the street or friends. Purple microdots were known to be strong but reasonable dosage. So start small and add more after 40 minutes if it's too mellow yellow.
Again only with a friend.
exHippie
Bye
(Score: 1) by fustakrakich on Friday August 21 2020, @02:36AM (2 children)
Blotter is, or was the safest. I don't trust any synthetics now.
La politica e i criminali sono la stessa cosa..
(Score: 1) by gmby on Friday August 21 2020, @03:24AM (1 child)
Purple microdots were available from midnight pharmacy labs. With known dosage and reliable ingredients. Made by people with knowledge. Blotter was a crap shoot. Window pain was just that a pain, always different each time.
Again; don't do it. Not worth it now days. Even then it was crap. But... at least people were not trying to kill you with it.
Micro dosing mushrooms (for depression) sounds interesting; but I have people whom depend on me, so no not worth it. Depression is best dealt with a full frontal attack with all my mental functions working. Keep busy and eat right. Works for me. Oh and Music... upbeat only.
Bye
(Score: 1) by fustakrakich on Friday August 21 2020, @03:30AM
Don't care much for synthetics there either. Stretch a string on a gourd and play a tune
La politica e i criminali sono la stessa cosa..
(Score: 2) by Bot on Friday August 21 2020, @07:22AM (3 children)
Jeez guys, if you want to destroy your brain just consume mainstream media. It is legal. Avoid lefty media at the beginning, that's too hardcore.
Account abandoned.
(Score: 1) by gmby on Friday August 21 2020, @05:53PM (2 children)
What do you know about brains? Your just a lowly Bot.
;)
Bye
(Score: 2) by Bot on Friday August 21 2020, @10:39PM (1 child)
Spotted the junkie...
Account abandoned.
(Score: 1) by gmby on Saturday August 22 2020, @02:24AM
No... That's Mr Crackhead for you Mr Rust Bucket. ;-)
I have some 1950's Singer sewing machine oil in a can if you need it.
Anyway... been away from all that stuff for so many years I quit counting.
Bye
(Score: 0, Insightful) by Anonymous Coward on Friday August 21 2020, @02:59AM (6 children)
Every single fucking time an article about astrophysics, cosmology, particle physics, etc is published on this site or one of the many other science oriented sites on the internet, hords of know-it-alls almost instantly post their nonsense in the comments, shamelessly displaying their ignorance and ineptitude to the entire world. It's as if they actually want the whole world to see how clueless and ignorant they are.
I know some are trolls, but as for the others, do they actually think that some random basement dweller who's never accomplished anything noteworthy in his miserable, empty, worthless life actually knows better than PhD's who've studied for years and worked for decades in their respective fields ? Are they actually successful in deluding themselves into thinking they're special, unique, and have some kind of innate insight that makes them superior to all these people ? That somehow they're the next office clerk that will come up with the theory of quantum gravity or something ?
Gosh these people are pathetic.
(Score: 2) by HiThere on Friday August 21 2020, @03:32AM
Well, it *has* happend. Not bloody often of course, but consider Enrico Fermi.
Javascript is what you use to allow unknown third parties to run software you have no idea about on your computer.
(Score: 0) by Anonymous Coward on Friday August 21 2020, @03:44AM (1 child)
No one wants to hear about this worthless dark matter theory anymore. It has zero predictive skill and cant be used to accomplish a single thing even in principle.
Its just invisible spheroids of mass you put in after you find your prediction is wrong... No advances in space exploration or anything cool can ever be advanced by dark matter theory, only hindered.
(Score: 3, Funny) by Bot on Friday August 21 2020, @07:23AM
unfortunately. Black Matter Lives.
Account abandoned.
(Score: 0) by Anonymous Coward on Friday August 21 2020, @06:40PM (1 child)
It sounds to me that you are insecure about people posting something that may make the published articles look bad?
(Score: 0) by Anonymous Coward on Saturday August 22 2020, @03:47PM
and if Anonymous Coward on Friday August 21, @02:59AM (#1039699) isn't insecure about people posting something that might make the establishment look bad then what does he care if we comment on the article and give our opinions? What's it to him if we're right or wrong, why should he be so bothered about it? If he doesn't like it he can simply not read the comments, no one is forcing him to stay here and read these articles or our comments.
We want to read the articles and comment. Not many here claim to be an expert and most people aren't. But how are we hurting anything?
(Score: 0) by Anonymous Coward on Wednesday August 26 2020, @09:45PM
We ... astrophysicist and cosmologist have set a low bar for themselves unfortunately. Lets take some items from the article shall we: "we live in a universe dominated by dark matter". Ah yes, lets start with a fudge factor (dark matter) and say it dominates the universe (more like dominates somebodies equations) and then pretend everything is absolute correct with that statement. In other fields I'd call that a strawman, but heh, its true in their minds so it must be true everywhere. Then we extrapolate upon an extrapolation which is approaching madness.
And then there's "something acts to suppress or shut down the formation of new stars across galaxies". Well heh, why don't we get more work on STAR formation properly working before we worry about galaxies? Kinda weird right? Maybe if we actually understood star formation there wouldn't be "something acting" upon things? Yes dust gets charged (Cosmic rays, etc), and clumps together to former larger DUST. And only DUST. Once you approach the size of a grain of salt the physics are completely different and they bounce instead of stick and we know of NO MECHANISM to make salt-sized particles stick together. Gravity and strong force certainly aren't doing it. I know, I know, horse if front of the cart, how you going to get research money for that?????
I also find you faith in PhD's to be disturbing. Don't get me wrong, I've known some fantastically smart people who happen to have a PhD, but in my experience, one 1-in-3 PhD's are truly earned. Most of the time I'd rather have a Bachelors graduate who at least doesn't figure he's (and very occasional she's) learned everything already. As a matter of fact the Real Smart People(tm) are ONLY the ones who keep learning through their entire lives. NOT working in their field for decades but LEARNING in their field and hopefully one or two other fields as well. And I've know some who never got ANY degree and are still working as engineers (one even as THE Senior engineer in the company). Smartypants does NOT come on a piece of paper and unfortunately too many astrophysicist and cosmologist are more than willing to prove that point.
I do agree though that to many people are more than willing to display their ignorance on this and the green site. It used to be way better. And to boot, most of the comments aren't helpful anymore and actual dialog like it used to be.
And yes, I am a astrophysicist and a rocket scientist and work with satellites (last one is a minor part of my life but far more than most people here).
(Score: 1, Interesting) by Anonymous Coward on Friday August 21 2020, @06:04AM (1 child)
As the universe gets older, the average age of stars in the universe will also get older. Why should that be a surprise? Red dwarfs live for trillions of years. The universe is young enough that no star with less than than 0.8 solar masses has ever died, at least not as a result of fuel exhaustion. Bright blue stars, on the other hand, die quickly.
Imagine you have a bucket of change. Every couple of months, you go through and take all the nickels, quarters and dimes to the bank, but you leave all the pennies. Over time, your bucket of change will get full of pennies. This does not prove anything about the number of coins in circulation. Statistically, it is called survivorship bias.
Quenching is not a particularly new idea, and it does slow down star formation, but it doesn't stop it. 3/4 of the gas in the galaxy is free gas, not bound up in any stars, and some fraction of the mass that is currently part of stars (especially sunlike and larger stars) will be returned back into the galaxy. Most of that free gas will eventually end up as part of a star, often more than once. The universe is only about 1/10000 of the way through the stelliferous (star-forming) era. Formation of stars will slow, and more and more of the matter will be tied up in red dwarf stars that don't return much of their hydrogen back into interstellar space. But that is a lot of time to form stars. Probably, rather than "almost all" of the stars having already been formed, it is only a small fraction of them. The stars coming later will become less and less impressive, but they'll still be stars.
(Score: 2) by Bot on Friday August 21 2020, @02:52PM
>As the universe gets older, the average age of stars in the universe will also get older.
not necessarily. Suppose a lot of stars turn out to be female. After year 29 their age will mysteriously freeze or be undecipherable.
Account abandoned.
(Score: 2) by Phoenix666 on Friday August 21 2020, @12:50PM
By a strange trick of parallelism, The Universal [universalpictures.com] has also made almost all the stars it will ever make.
Washington DC delenda est.