Slashdot Mirror
Scientists Capture First Image of Dark Matter Web (inhabitat.com)
Kristine Lofgren writes: Scientists have long suspected that the universe is woven together by a vast cosmic connector but, until now, they couldn't prove it. Now, for the first time ever, scientists have captured an image of a dark matter bridge, confirming the theory that galaxies are held together by a cosmic web. Using a technique called weak gravitational lensing, researchers were able to identify distortions of distant galaxies as they are influenced by a large, unseen mass -- in this case, a web of dark matter. In order to create a composite image that shows the dark matter web, scientists had to look at more than 23,000 galaxy pairs located 4.5 billion light-years away. "Results show the dark matter filament bridge is strongest between systems less than 40 million light years apart," reports Phys.Org. The findings have been published in the journal Monthly Notices of the Royal Astronomical Society.
Looks like an onion, right?
From TFA, "...researchers were able to identify distortions of distant galaxies as they are influenced by a large, unseen mass, such as dark matter." That means that what they have are images that appear to imply the existence of Dark Matter, and are hard to explain any other way, not that the images actually show us Dark Matter. That doesn't mean that it doesn't demonstrate that Dark Matter exists, it's just that the images aren't as cut and dried as the article's headline implied. It also means that there's still wiggle room for those who are certain that it doesn't exist. Still, it's a great step in the right direction.
Good, inexpensive web hosting
Where was dark energy debunked?
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
https://science.slashdot.org/s...
If you consider a simulation 'debunking'. Given that it was only posited to exist due to mathematical calculations, that's good enough for me.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
Here, let me correct that:
Scientists Manufacture First Visual Representation of Gravitational Anomalies Inconsistent With Observed Matter
There has never been what I would consider "evidence" of dark matter, just evidence of a lack of understanding of matter, gravity, or space.
Astrologers are kicking ass this month!
Aries, the Ram, is quite good at that.
"First they came for the slanderers and i said nothing."
That's your 'refutation'? They made it up? lol. They have credibility, you don't, enjoy your frustrated irrelevance. DM almost certainly exists.
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
Capture? Realy? I would say "Computer generated..)
Dark matter does not exist, Dark matter is just the name of a theory that scientists have come up with to describe some anomalous gravity data they got when they looked at how the universe was put together mainly how galaxies interact with each other.
As they could see something is interacting with the galaxies yet they could not directly detect what is causing the interaction they called it dark and as the general consensus is that in order for this amount of interaction it has to come from somewhere and the only stuff in the universe that we currently know can interact with gravity on this scale is matter the theory is that some kind of undetectable matter exists so they called it dark matter but the theory does allow for other kinds of causes of the interaction. Its an ongoing evolving theory like all theories.
Talking about dark matter like it is actual stuff is the same when people talk about anonymous like its an actual group instead of a descriptor or talking about the public when it could mean anyone.
The theory and picture is till cool though.
DM almost certainly exists.
Go on, tell us all about it.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
In the Einstein universe, are they (matter & energy) not simply different states of the same thing?
Yes if one isn't being super pedantic. Your "states" analogy is reasonable. To say matter and energy are the same thing isn't exactly accurate but it's good enough for all but the most picky of purposes. But applying that relationship to so called dark matter and dark energy is a little bit fraught because we don't actually know what dark matter and dark energy are. As a result you are understandably conflating some things.
The terms "dark matter" and "dark energy" are sort of placeholder terms to explain some phenomena that we don't entirely understand yet and they are more marketing terms than precise terms of art. We don't actually know for certain that what we call "dark matter" is actually matter or that "dark energy" is actually energy. We just have some observations we haven't been able to adequately explain so we needed some short hand terms to explain what we are seeing in terms of the models we have. One of three things is happening. Either we are seeing something new, we are making measurement errors, or our models are wrong. Possibly some combination of all three.
Dark matter arises out of the fact that we see some observations that don't make sense based on the amount of baryonic ("normal") matter we can quantify. Our models of how gravity works tell us that for our observations to match our models there must be a lot more matter than we can see presuming our models are correct. So called dark energy arises out of our observations and measurements of the rate of expansion of the universe but it's even less well understood than dark matter.
Being that mass and energy rarely appear separately, would not the presence of 'dark energy' strongly infer the existence of 'dark matter'?
Mass is not the same thing as matter. You can have matter without mass such as with a photon. Mass is a property in some forms of matter, all of which move slower than c (the speed of light).
Dark matter does not exist
Dark matter certainly might exist. Or it might be measurement error. Or it might be model flaws. We simply aren't sure at this point. No one can say with any certainty that dark matter does not exist because the data isn't conclusive either way. Yes "dark matter" is something of a placeholder marketing term but it describes what appears to be a very real phenomena. There is some reasonable evidence to suggest dark matter is a real thing but none of it is conclusive at present. We have considerable confidence in some of our measurements so we have good reason to believe that measurement error is the least likely of the three possibilities. I've never heard a slam dunk explanation as to why we should favor dark matter being real over model error but I trust the professional physicists to sort it out in due course.
Dark matter is just the name of a theory that scientists have come up with to describe some anomalous gravity data they got when they looked at how the universe was put together mainly how galaxies interact with each other.
And that theory posits that there may be some form of matter we currently cannot directly observe. We don't know if that is the actual explanation but it's a necessity under current models if we presume they are correct.
Nobody else missed a word in the title and was trying to figure out why scientists would be taking pictures of or trying to prove the existence of the Dark Web?
I like how if you keep scrolling down the first link given in the article, you end up with "HOW TO: Grow an Avocado Tree from an Avocado Pit"
This is so much more useful than some silly dark matter pictures!
I tend to rant.
When I saw that article a couple weeks back, I looked at the headline, then the date, and closed Slashdot.
Surprised to find it's an actual article.
This Apr 1st, the stories all seemed to be actually true with slightly warped headlines and such subjects as that they all seemed to be hoaxes. (Only actually checked a couple)
https://en.wikipedia.org/wiki/Inverted_totalitarianism
Does this Dark Matter Web have a URL?
#DeleteFacebook
but i thought the movement of galaxies WAS the expansion of the universe.
The movement of the galaxies can help us measure and observe the expansion of the universe but isn't the expansion itself. To use a simpler example, imagine a galaxy is an ant and that ant is standing on the surface of a balloon. The ant can walk around the balloon which is equivalent to the galaxies moving through space. Now inflate the balloon. The ant is moved because space (the balloon surface in this example) became larger but it wasn't because the ant itself moved. What happened is space expanded and everything in space moves a bit further apart as a result. But those objects in space (ants) are still free to move through space so the expansion of space doesn't explain everything we see by itself.
What we see is the galaxies moving (mostly) away from each other through space AND we see space expanding because they are moving away from each other faster than can be explained by simple movement through space. Space can expand faster than the speed of light because c is only the speed limit for matter moving through space. Space itself can expand arbitrarily fast as far as we know.
There appears to be a whole anti-DM subculture.
I don't think there are "anti-DM" people here outside of maybe a few wingnuts. There are lots of pro-evidence people here, myself included. The problem with dark matter is that there are at least three possible explanations, none of which have been conclusively ruled out. 1) Dark matter is indeed some form of matter as yet not fully understood, 2) Our measurements are in error somehow, and 3) our models for forces (gravity) are incorrect somehow.
I have a minor in applied physics so I'm not entirely uninformed though I'm not an expert. But I have yet to hear a single professional physicist clearly explain why we should favor the existence of dark matter as a preferable explanation to error in measurements or modeling errors. They seem to be strongly favoring dark matter being a real thing but all our "evidence" for it is indirect. It's perfectly reasonable that it might be explained by a better model similar to how relativity supplanted Newtonian mechanics. Invoking some form of exotic matter is perfectly reasonable too but the problem is that we have precisely zero direct measurements of such a thing. Until we do it's an open question.
A spokesman for the RIAA said, "This 'Dark Matter Web' is clearly only being used for illegal downloads! We must destroy it!!!"
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
...
If what they recently proposed about the expansion of the universe is true (that space does not expand evenly everywhere in the universe, because it primarily expands in the presence of galaxies), then perhaps it actually compresses between galaxies, and gravity waves are refracted as they pass through.
That article is about dark energy, not dark matter. Two entirely different things with similar names. It's like saying my browser can't use Javascript because Java is disabled.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes
should move to the dark-matter-web, a mesh of such complexity that not even God can find it.
If you must moderate, please moderate as irrelevent, not something bad, because I'm sure someone will find this interest
Dark matter makes up about a quarter of the universe, but it is difficult for us to detect it because it doesn’t reflect or shine light.
Or block light. That is the more important property I would think.
Those who do not learn from commit history are doomed to regress it.
Aw, it's been years since an electric universe nut posted on Slashdot. Happy memories!