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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.
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.
It must have been something you assimilated. . . .
They found some of the missing baryon matter. This is the normal matter that is around us every day. Dark matter is stuff that has momentum and exerts a gravitational field but doesn't interact electromagnetically, so we can't see it. We believe most of the matter in the universe is dark matter but we also believe there is a lot more of the normal baryon matter out there but we just don't know where or what it is. These studies have shown that there are filaments of hot gas stretching between galaxies. The density of this gas is extremely low but the volume it occupies is huge so it contributes to a large amount of the baryon matter in the universe.
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.
I browse on +1 so AC's need not respond, I won't see it.
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 believed there had to be an "Ether" in which light waves could propogate, because it was the only reality they could model. When Michaelson and Morley showed that the speed of light was independent of direction of travel, physicists scrambled to attribute various properties to Ether to account for their findings. Einstein ended up modelling a reality where the speed of light was a universal constant, and his model was eventually proven to be more accurate than the etheric model.
It's very likely we'll never "see" dark matter. Likely we'll find a better model of the universe, something that makes gravity weaker at intergalactic distances, and dark matter will go the way of Ether. I'm less well versed in dark energy, but I bet it'll turn out to be something that vanishes too once we have a better universal model.
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/...
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.
No.
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").
Nope, this "found" matter was already accounted for in the known matter area. The amount of dark matter / dark energy hasn't changed.
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't seem to explain things either (this is called the small scale problem). So there are proposals for "warm/cold" dark matter. And nobody really has a clue about dark energy... So yes, details "matter".