Half the Universe's Missing Matter Has Just Been Finally Found (newscientist.com) 247
An anonymous reader shares a report: The missing links between galaxies have finally been found. This is the first detection of the roughly half of the normal matter in our universe -- protons, neutrons and electrons -- unaccounted for by previous observations of stars, galaxies and other bright objects in space. You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull. But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far. Two separate teams found the missing matter -- made of particles called baryons rather than dark matter -- linking galaxies together through filaments of hot, diffuse gas. "The missing baryon problem is solved," says Hideki Tanimura at the Institute of Space Astrophysics in Orsay, France, leader of one of the groups. The other team was led by Anna de Graaff at the University of Edinburgh, UK. Because the gas is so tenuous and not quite hot enough for X-ray telescopes to pick up, nobody had been able to see it before.
Titles are adding in words for the hell of it (Score:5, Insightful)
"Just been finally found"?
How about "Just been found" or "Finally been found"?
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Sadly that headline was copied verbatim from the New Scientist story.
Re:Titles are adding in words for the hell of it (Score:5, Funny)
Sadly that headline was copied verbatim from the New Scientist story.
Or, rather, had just been finally copied.
Re:Titles are adding in words for the hell of it (Score:5, Funny)
Or, rather, had just been finally copied.
Much yes. So grammar. Wow.
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Well, English isn't Science.
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Tell that to a cunning Linguist, you insensitive clod!
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https://www.youtube.com/watch?... [youtube.com]
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To make matters worse, as opposed to the summary the headline makes it sound like they only found half of the missing matter.
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Hey, the phrase "6 or 1/2 dozen of the other" has now been scientifically quantified!
But you can't tell which is which until you open the box of donuts.
Not half: only 2% or 7% depending... (Score:5, Insightful)
So, I suppose if you just refer to matter alone then ~ 7% of the missing matter of the universe has been found but that is still nowhere near 50%, to claim that much you have to specify "50% of baryonic matter" or find Dark Matter (but in that case it would probably be a lot more than 50% found).
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I knew this already because logically, if the Enterprise D only needed one baryon cleaning sweep in a seven year run there can't be that much of it. 4% sounds about right.
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"Just been finally found"?
How about "Just been found" or "Finally been found"?
Discussing the semantics of the title is absurd, because the notion the matter was "missing" is absurd. It was always there, we were just too blind to see it.
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It's OK, it had just slipped down behind the sofa. Should have checked there in the first place.
Oh, and we also found a pile of spare change, and Obama's original birth certificate.
Summary is wrong - not about dark matter (Score:4, Informative)
Re:Summary is wrong - not about dark matter (Score:5, Informative)
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The title says "matter" and whatever Dark Matter is it is most definitely matter so either the reference to "matter" is wrong or the 50% number is wrong because what is described is not the discovery of 50% of the missing matter in the universe, only 50% of the missing baryonic matter.
So what you are saying is that you didn't even bother to read the summary, much less the article or the actual papers linked in the article, and you are arguing the validity of all that based on the headline?
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They could have said that they found neutrons or protons which would have been much easier to understand for most people here.
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Ah, like the neutrino then, some type of matter that was postulated to make the numbers balance.
Re:Summary is wrong - not about dark matter (Score:5, Informative)
Dark matter was/is the explanation for the missing regular matter. Less missing regular matter, less dark matter.
The only data for dark matter is gravitational lensing in excess of what was accounted for by the previously known regular matter. All those numbers need to get run again in light of this discovery.
Science reporting sucks.
We suspect a certain amount of normal matter, and a certain amount of dark matter in the universe. All this study did was help confirm that we were right about the amount of normal matter out there. It has no effect, at all, on the amount of dark matter science thinks is out there as well. It didn't shift the totals one bit.
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We know there is a certain amount of total mass. We don't know how that breaks down.
This is incorrect.
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You are profoundly ignorant on the subject, and yet you feel obligated to make pronouncements about it. You must be a /. regular!
Really, if you are unaware - as you clearly are - that it is the rotation of galaxies, like the nearly Andromeda, and our own, that were the first evidence of the existence of dark matter then you know nothing about the subject.
Try reading the Wikipedia page which lists ten different pieces of evidence showing its existence, with links to further material on each.
Baryon Lives Matter (Score:2)
So, heat means energy, right? (Score:2)
Does that matter exist between stars and not only between galaxies? Can it be used as fuel for spaceships? Inquiring minds want to know.
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Can it be used as fuel for spaceships?
In a science fiction story, sure.
In reality, no - it's far too sparse.
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Comets have a tail (Score:2)
It only makes sense for something as large as a galaxy in motion to shed a bit during travel. They produce enough of their own light.
bad day for sci-fi (Score:2)
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Nope, as this is not about dark matter at all.
Yea I didn't realize reading comprehension around here was so bad. I mean I knew it wasn't great, but damn, this is needs a job coach to flip burgers bad.
Dang it! Scientist! Should you... (Score:2)
For small values of half maybe (Score:2)
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So by half the matter in the universe, we are taking 2.0-2.3% tops. [arxiv.org]
This is the first detection of the roughly half of the normal matter in our universe -- protons, neutrons and electrons -- unaccounted for by previous observations of stars, galaxies and other bright objects in space.
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TL;DR version (Score:5, Funny)
It was behind the couch along with all the missing cat toys, single socks and car keys. ;)
Re:TL;DR version (Score:5, Funny)
I just looked behind our couch and found exactly the same thing.
Which is odd because we've never had a cat. Or a car.
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Well, it solves the problem of how that one person got left at the end of the Swingers night though.
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but was the remote back there?
First time for everything! (Score:2)
I keep misreading this headline (Score:2)
And the other half... (Score:3)
And the other half... is AOL discs... am I right?
Scientists find OP's Mom (Score:2)
Re:Dark matter (Score:5, Informative)
I've been saying for years that "dark matter" and "dark energy" aren't really things. They're placeholders for some type of matter or interaction we'll discover later.
That we're finally able to detect these baryon filaments is a solid step in the right direction to finally solving the "dark" mystery.
Not quite. TFA and TFS say that Dark Matter exists *and* they just found the missing "regular" matter. (highlighting mine):
You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull.
But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far.
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Dark matter is literally a placeholder for matter we expect to be there but can't detect.
If we've found X more matter, that means there's X less dark matter out there.
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Nope, this "found" matter was already accounted for in the known matter area. The amount of dark matter / dark energy hasn't changed.
Re:Dark matter (Score:4, Insightful)
Nope, this "found" matter was already accounted for in the known matter area. The amount of dark matter / dark energy hasn't changed.
I understand that claim, but TFS sure as shit didn't make that clear.
Regardless, the entire premise of "dark matter" is that our observations of matter are incomplete.
It's fundamentally a "knowns, known unknowns, unknown unknowns" shell game.
You're claiming that this was part of the "known unknowns" because we "know" the sum of the "knowns" and "known unknowns". This may be what TFA is saying, but the very fact that we have an "unknown unknowns" category means we really don't "know" shit. That category was literally made up to make the math work given our assumptions.
Re:Dark matter (Score:5, Interesting)
You should check out the history of the discovery of the neutrino, a particle invented to make the maths work given our assumptions. Also very similar to dark matter as it barely interacts with normal matter.
Interestingly when Fermi refined the theory giving a neutrino, Nature refused to publish it as too far out there.
https://en.wikipedia.org/wiki/... [wikipedia.org]
The positron also was theorized first on the basis that Dirac's new theory allowed it. Though at first it wasn't considered as a new particle. https://en.wikipedia.org/wiki/... [wikipedia.org]
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You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull. But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far.
So yes, the article (and also the summary quoted) made it very clear that this discovery had nothing to do with Dark Matter and doesn't change any calculations regarding Dark Matter.
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You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull. But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far.
So this discovery does not change anything we postulate about Dark Matter.
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What the two teams detected
Re:Dark matter (Score:5, Insightful)
This has nothing whatsoever to do with dark matter or dark energy, and does nothing whatsoever to disprove the existence of either of those things. We knew this stuff existence, our models said it was in the intragalactic expanse, it's just it's hard to directly see because it's extragalactic: it's not inside stars, so it mostly doesn't emit light, and when it does it's not very bright.
In fact, I'd even go so far as to say that this is just more (indirect) evidence for the existence of dark matter: it helps confirm our models/simulations of galaxy formation, and those models don't work without dark matter, and considerable amounts of it (far more of it than the "missing" baryonic matter they found, in fact).
Re:Dark matter (Score:4, Informative)
No.
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As stated in other posts, the answer to the question "..we've now observed it and no longer require that "fix" in our valid maths. Right?" is "no". As the article states,
"This is the first detection of the roughly half of the NORMAL matter in our universe – protons, neutrons and electrons – unaccounted
Dark matter was a thing till scifi canned it! (Score:2)
Dark matter was a thing till scifi canned it!
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You can get canned Dark Matter? Where would I buy it? Can I get it pickled?
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200M should cover all rights and legal fees. also we can't take bit coin due to legal issues.
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You can get canned Dark Matter? Where would I buy it? Can I get it pickled?
You already have two cans of it, you just can't see them.
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I've been sitting on my can.
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I think you mean Syfy. And did they kill it off? I tried watching the latest season but I just couldn't care anymore.
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I don't give a dam for there new name!
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Baryon filaments have nothing whatsoever to do with dark matter or dark energy. Finding them is progress in validating current models since it finds matter that our current models say should be out there. It also strengthens the cause of "dark" matter/energy, since if our current models predict something (the presence of ordinary matter not currently detectable) that's verified by discoveries, it strengthens those models.
This still doesn't mean there has to be actual dark matter of course. Physicists once b
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I've been saying for years that "dark matter" and "dark energy" aren't really things.
Which would make you right, and in accordance with every scientist that's looking at this, anywhere. And when we find those types of matter, or interaction, or weird gravitational effect, or whatever, we'll likely still call it "dark matter". Does that mean it becomes a thing then, but wasn't before?
Anyway, this isn't dark matter, or energy, it's the missing baryonic matter. Baryonic just basically means "regular stuff". Dark matter means "something else, not regular stuff".
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No, Baryonic means pastry, and dark matter is what happens if you leave it in the oven for too long.
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You (and the submitter or editor) seem to think that baryonic matter is something exotic. It is not. Baryons are the family of particles that comprise exactly three quarks, and include the protons and neutrons that make up all known (and unknown) elements. You're almost entirely made of baryonic matter.
The real article says it's baryonic matter precisely to convey that it's mundane matter, and not mesons like pions or any of the really strange stuff like pentaquarks.
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My understanding is that the story is about finally "seeing" half of the hidden baryonic mass that was inferred to exist from other data. That suggests that there is still a more baryonic mass that we only infer exists; it remains hidden.
But that this has nothing to do with the dark matter and dark energy that is also inferred by current best theories.
Someone has made a comment suggesting that much of the dark energy is the "vacuum energy", which I take as a reference to the energy that is demonstrated in
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Your argument is persuasive. It is certainly possible that my failure to detect a second probable grammatical error of the same form as the first one had led me to a wrong conclusion.
Unfortunately the likelihood that there is a systemic failure to use proper grammar in the story destroys its credibility rather than clarifying anything.
This story is worthless. But the comments do suggest that filaments of baryonic matter exist between galaxies and have significant total mass. So there is redeeming value in
Re:Dark matter (Score:5, Informative)
This is the first detection of the roughly half of the normal matter in our universe -- protons, neutrons and electrons -- unaccounted for by previous observations of stars, galaxies and other bright objects in space. You have probably heard about the hunt for dark matter, a mysterious substance thought to permeate the universe, the effects of which we can see through its gravitational pull. But our models of the universe also say there should be about twice as much ordinary matter out there, compared with what we have observed so far.
This paper is talking about the missing non-dark matter that the current models said should be there. I had nothing to do with dark matter, and the matter they found has no impact on the expected amount of dark matter in the universe.
Dark Matter is the norm (Score:2)
This is the first detection of the roughly half of the normal matter in our universe -- protons, neutrons and electrons
Well technically since ~4% of the universe is made of protons, neutrons and electrons (baryonic matter) and ~25% is made of Dark Matter arguably "normal matter" is, in fact, Dark Matter since it is about 6 times more abundant by mass. Plus the headline is wrong since Dark Matter is matter too so really only ~7% of the missing matter has been found which is a lot less than 50%.
Re: Dark matter (Score:5, Informative)
You should really read the article. This isn't two independent groups scanning and suddenly discovering new pieces of the universe. It's basically a common data aggregating process applied to massive amounts of data to brighten faint emissions. Considering every star gazer with $5000 worth of equipment and a Mac does this every week, how many papers does that need to prove itself?
Of course the next step is to test it across more spots in the universe to hopefully find anomolies.
Hot gas in a cold universe? (Score:2)
Would just cool down by emitting IR. Hot gas needs something to keep it hot, like a nearby star.
The article does not make sense.
Re: Hot gas in a cold universe? (Score:3)
Sorry, I had it in reverse. They detected the gaps in the light left from the Big Bang. Basically shadows of the gas particles. The lukewarm gas itself doesn't emit anything detectable. Put together a bunch of pictures of microscopic gaps and you can build up a shadow of a mass in the shape of a thread.
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And I stand by my statement about three peer-reviewed papers.
Well if you read to the bottom of TFA, there are links to two papers. So just need one more to shut you up then?
Re:Dark matter (Score:5, Informative)
Apologies, but almost all of this is wrong.
Models based on observations indicated that 4% of the universe's mas/energy composition had to be normal, baryonic matter. Half of that 4% was missing until today. Dark matter, based on observations, needs to be approximately 23% of the mass of the universe. Otherwise galaxies would not have formed and would spin apart. Further, most of the mass of dark matter is associated with galaxies, and this matter was found between them. Details "matter" (unless of course they "energy").
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Apologies, but almost all of this is wrong.
Models based on observations indicated that 4% of the universe's mas/energy composition had to be normal, baryonic matter. Half of that 4% was missing until today. Dark matter, based on observations, needs to be approximately 23% of the mass of the universe. Otherwise galaxies would not have formed and would spin apart. Further, most of the mass of dark matter is associated with galaxies, and this matter was found between them. Details "matter" (unless of course they "energy").
Perhaps I'm mistaken, but according to current theories (e.g., the standard 6-parameter lambda-CDM model)...
~4% baryonic matter
~23% dark matter (needed to explain formation of galaxies and larger scale structures)
~73% dark energy (needed to explain observed expansion rate of the universe)
This current discovery only addresses part of the postulated, but previously unobserved 4% baryonic matter.
FWIW, Dark matter is a bit a kludge in that a single type of dark matter in the model (cold dark matter) doesn
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Or maybe "Swings Again", depending on how you take your puns...
Re:The simplest answer is often the correct one. (Score:4, Informative)
Completely agree with you - Occam's Razor Wins Again...
That's a butchering of Occam's Razor. The law is about preferring the most parsimonious hypothesis, i.e. the one that makes the fewest assumptions.
Dark matter being composed of a diffuse gas of standard baryonic matter could be the simplest hypothesis, but it makes many assumptions by implicitly refuting consolidating evidence against it. Wikipedia lists a few of them: https://en.wikipedia.org/wiki/... [wikipedia.org]
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Shit? There's a bomb?
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Shit? There's a bomb?
Yes, there will be a rapid diffusion of gas, if you don't defuse it first.
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Dark matter is as dark matter does
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How diffuse would that defuse gas be?
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The article doesn't say that some of the dark matter has been accounted for by this gas, but rather, some missing "regular" matter.
The supposed amount of dark matter in the universe doesn't change a bit based on this discovery.
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> we can observe it's gravitational interactions
Perhaps it's made of superfluous apostrophes?
Re:So where is the other missing half (Score:5, Funny)
Well let's hope they find it all at once. Because if they keep only finding half of what's missing we could be here forever.
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Well let's hope they find it all at once. Because if they keep only finding half of what's missing we could be here forever.
Wow, that was brilliant. I love your brain, whoever it is.
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Something to do with socks and dryers, no doubt.
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Something to do with socks
Nope. Socks are the larval stage of wire clothes hangars.
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The ignorance of the average slashdot poster. I thought everyone knew that paperclips are embryo wire clothes hangers.
Connecting? (Score:2)
The fact that these "filaments" are strung from one galaxy to another suggests they are clinging to or following some kind of structure, no?
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You have to think of it more like the stringy bits of cheese when you tear a slice off a pizza. Or the vomit running off your chin after 10 pints of lager, 5 large whiskies and an extra large four cheese pizza. It can help understanding to picture the universe as a mixture of alcohol, doughy cheese and stomach lining.
Re:Connecting? (Score:4, Funny)
Neurons and synapses. The universe is a brain.
The cool kids are spelling it "brane" now.
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Re: So where is the other missing half (Score:2)
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Slashdot of all places should get the summary right. It sounds uneducated when they treat baryons as a distinct type of particle rather than a category that includes many familiar ones.
Re: 'Particles called baryons' (Score:2)
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Let me know when they are finally able to detect the infinite amount of matter the universe actually has, as well as its infinite everything else.
You do understand, right, that in an infinite universe (with, by extension, an infinite amount of matter if you want to think of it that way) can be a thing while still not manifesting itself as an infinite amount of matter (or even hardly any matter at all) in any particular volume. Right? You get that part?
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The century has just began, at the current rate, I'm pretty sure that the century will have much greater claims.
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you just wasted my reading skills
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Hillary lost. Get over it.
Not until he gets his first edition, hardbound copy of "What Happened" signed and put in a display case.