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Half the Universe's Missing Matter Has Just Been Finally Found (newscientist.com)
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.
"Just been finally found"?
How about "Just been found" or "Finally been found"?
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).
"None can love freedom heartily, but good men; the rest love not freedom, but license." --John Milton
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.
It's also not half the missing matter. Dark Matter is matter just not made of atomic constituents (protons, neturons and electrons) generally called baryonic matter. Only 4% of the universe is made of baryonic matter which, if the summary is correct and the half of this which was missing has been found this means that only 2% of the missing mass-energy of the universe has been discovered. There is a remaining 25% of the mass-energy of the universe in Dark Matter (which is still matter, just not baryonic) and ~71% which is Dark Energy which is the vacuum energy.
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).