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Dark Matter Filament Finally Found
An anonymous reader writes "Everyone is talking about the recent Higgs boson announcement by the scientists at CERN, but another significant scientific discovery was revealed this week as well. In a study published online in the journal Nature on Wednesday, scientists show that they have successfully found the first dark matter filament."
http://www.space.com/16412-dark-matter-filament-galaxy-clusters.html
Futurama fans already know that that filament is a result of Nibblonian diarrhea being ejected into space.
My kingdom for a donkey!
what colour are they ?
The dark lightbulb. The darkbulb?
Vote monkeys into Congress. They are cheaper and more trustworthy.
First of all, don't go to "page 2" and I use that term loosely. Secondly, it doesn't mention a single scientific detail about how they determined that the light was being bent around a filament-shaped object compared to the starts behind it actually being in the location the light suggests. It merely states "They used a model to subtract out the masses of the galaxy clusters and then fit the remaining mass with a model of what a filament might look like. They found that a filament must be present." So in other words, they didn't find anything other than a mathematical equation suggesting dark matter exists. Congratuations are in order indeed.
Aha, someone posted a hair bit of time ahead of me a much better article so let me ammend that with the short version:
There are 2 galaxies kinda far apart but they're really overlapped from Earth's point of view. Like one is almost entirely behind the other. So the back galaxy's light passes along where the filament would be estimated to be between the galaxies. So the light travels through the dark matter's gravitational field for a really long time, running practically parallel to the filament. Even after that much light gravity tugging, it's barely perceptable by our current telescopes. So someone had some pics of this set of galaxies from 2001 but never did anything with them because they didn't realize the opportunity. This new team noticed it, compared it to background light to detect additional possible lensing, and discovered unmistakeable slight lensing. So something is obviously there and it has to be a particular shape, density, and reflect no light.
Dark Matter was proven decades ago as this following article demonstrates.
Bell Labs Proves Existence of Dark Suckers
For years it has been believed that electric bulbs emitted light. However, recent information from Bell Labs has proven otherwise. Electric bulbs don't emit light, they suck dark. Thus they now call these bulbs dark suckers. The dark sucker theory, according to a Bell Labs spokesperson, proves the existence of dark, that dark has mass heavier than that of light, and that dark is faster than light.
The basis of the dark sucker theory is that electric bulbs suck dark. Take for example, the dark suckers in the room where you are. There is less dark
right next to them than there is elsewhere. The larger the dark sucker, the greater its capacity to suck dark. Dark suckers in a parking lot have a
much greater capacity than the ones in this room. As with all things, dark suckers don't last forever. Once they are full of dark, they can no longer suck. This is proven by the black spot on a full dark sucker. A candle is a primitive dark sucker. A new candle has a white wick. You will notice that after the first use, the wick turns black, representing all the dark which
has been sucked into it. If you hold a pencil next to the wick of an operating candle, the tip will turn black because it got in the path of the dark flowing into the candle.
Unfortunately, these primitive dark suckers have a very limited range. There are also portable dark suckers. The bulbs in these can't handle all
of the dark by themselves, and must be aided by a dark storage unit. When the dark storage unit is full, it must be either emptied or replaced before
the portable dark sucker can operate again.
Dark has mass. When dark goes into a dark sucker, friction from this mass generates heat. Thus it is not wise to touch an operating dark sucker.
Candles present a special problem, as the dark must travel in the solid wick instead of through glass. This generates a great amount of heat. Thus it can be very dangerous to touch an operating candle. Dark is also heavier than light. If you swim deeper and deeper, you notice it gets slowly darker
and darker. When you reach a depth of approximately fifty feet, you are in total darkness. This is because the heavier dark sinks to the bottom of the lake and the lighter light floats to the top. The immense power of dark can be utilized to mans advantage. We can collect the dark that has settled to the bottom of lakes and push it through turbines, which generate electricity and help push it to the ocean where it may be safely stored.
Prior to turbines, it was much more difficult to get dark from the rivers and lakes to the ocean. The Indians recognized this problem, and tried to
solve it. When on a river in a canoe travelling in the same direction as the flow of the dark, they paddled slowly, so as not to stop the flow of dark, but when they traveled against the flow of dark, they paddled quickly so as to help push the dark along its way.
Finally, we must prove that dark is faster than light. If you were to stand in an illuminated room in front of a closed, dark closet, then slowly open the closet door, you would see the light slowly enter the closet, but since the dark is so fast, you would not be able to see the dark leave the closet.
In conclusion, Bell Labs stated that dark suckers make all our lives much easier. So the next time you look at an electric bulb remember that it is indeed a dark sucker.
This has already been considered, but the current cosmological models and experimental evidence requires that the majority of dark matter be non-baryonic, i.e. composed of particles that are incapable of forming atoms and thence stars and planets.
Non-luminous normal matter absorbs light (and so becomes luminous normal matter evenutally, at least at some frequency).
BTW, the confirmation for dark matter vs other theories for galaxy rotation came from the WMAP data. IIRC, about 80% of the early matter of the universe was shown to be somehting that interacted gravitationally, but did not interact with light (or electrons). The actual % of dark matter measured matched the amount predicted by the dark matter hypothesis for galaxy rotation rates, which is a pretty convincing confirmation IMO.
Socialism: a lie told by totalitarians and believed by fools.
And it turned out that it was made of what we long suspected the mising mass of the universe wa composed of: AOL discs.
Well, except that if 80% of the mass in our galaxy was simply non-luminous, we'd still see the "haze" from it, just as we can see evidence of the existing hydrogen haze by it's characteristic absorbtion spectra, especially when starlight passes through nebula where the diffuse matter density is extremely high. Perhaps the vast majority simply formed gas giants and the like that were two small to "ignite", recent evidence does suggest wandering planets may be far more common than star-bound ones, but to get the 5:1 ratio still we'd be talking about 5000 Jupiters for every sun, and the sun is actually pretty tiny as stars go - with that many dark planets whizzing around it seems likely we'd see some evidence of them, likely of the frequent "Gas giant zooms through solar system, multiple planetary orbits disrupted, news at 11" sort. If the planets were smaller the "invasions" would be even more frequent, and if they were much larger (we're not sure of the exact limit) they'd spontaneously ignite
Then again - if using general relativity rather than Newtonian gravity actually does explain the odd rotational characteristics of our galaxy without reliance on massive amounts of additional matter then you may be right. There's still things like the Bullet Cluster that show evidence of something very weird going on though - the gravitational lensing seems to have become partially disconnected from the visible matter - if "dark matter" was simply non-luminous you would expect it to still have distribution and gravitational-collision properties similar to the glowing stuff, which is not the case there. Whatever is causing the lensing is behaving in a manner fundamentally different than the matter we can see, in fact it appears to be largely unaffected by the collision at all, which would seem to at odds with many "simple" dark matter theories as well (i.e. it's like normal matter, except light passes right through it).
--- Most topics have many sides worth arguing, allow me to take one opposite you.
I'd call this bigger than the Higgs.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
In a world where people are only comforted by thinking they understand how the universe works I'm totally fascinated by the unexplainable. It boggles my mind that people couldn't believe in 'invisible' mass. Furthermore, I look forward to what organisms may exist in that phase. Maybe Deadmau5's got it. Ghosts n stuff.
Higgs was pretty much a given. All that CERN did was confirm it. OTOH, Dark matter occupies a large amount of the universe and yet, we have not found it. So, the question is, is this real?
I prefer the "u" in honour as it seems to be missing these days.
Actually, it generally goes the other way - when a non-star initially forms it will be hot, and has to radiate all that energy away, becoming less bright until it eventually becomes effectively non-luminous. Starlight simply isn't dense enough to significantly heat anything substantially - it will be radiated away as fast as it gets absorbed, and that's *way* below what we can currently detect. Our telescopes may eventually become sensitive to detect such MACHOs directly, but they're not there yet. And micro-lensing studies seem to limit them to comprising roughly the same amount of matter as luminous objects unless they're predominantly >100 solar masses (which would likely tend to be radiant) or less than Moon-sized, in which case there would need to be so many of them that they would likely be passing through the solar system on a fairly regular basis, which we haven't seen.
If we're talking about stuff in intergalactic filaments though - well, they make interstellar space look positively dense, anything non-luminous would be so close to absolute zero, and so far away, that it would be effectively invisible unless directly in front of something. And it would have to be in a pretty frakking dense cloud to significantly blot out a galaxy Remember that as a wave light will bend around any object in it's path, not much, but slightly (this effect is completely separate from gravitational lensing) and over intergalactic distances that's enough that the "cumulative effects" of a million individual objects each blocking one millionth of the "disc" of a distant galaxy will be far less than you would expect.
As for galactic rotation and WMAP - there is correlation there, I'll give you that, and when two independent measures give you similar results you should probably sit up and take notice. However, when something like the general-relativity explanation for galactic rotation speeds comes along and says - "Hey, you know that really weird behavior we couldn't explain that made us come up with a really bizarre theory to explain? Well we finally have the computational power to run the analysis using the currently accepted theory of gravity instead of the much simpler but known-flawed centuries old model, and everything works out pretty close to what we actually see." Well, that should make you take notice as well. In fact that should make you sit back and take a long hard look at all your "cosmological gravity weirdness", because most of that happens on a scale where galactic distances look positively local, so you'd expect the discrepancy between instantaneous Newtonian gravity and GR gravity to be even larger.
Astronomy is a somewhat shaky field - all theories are fundamentally untestable - all you can do is look out at the universe and try to find phenomena that seem to support or counter theory, but in doing so you're making numerous assumptions about what exactly you're looking at to begin with, and assuming it behaves in a manner consistent with other widely accepted but still fundamentally untestable theories. Now that technique is surprisingly effective, but it is vulnerable to flaws in analysis, especially when much analysis is based on something that is known to be inaccurate (Newtonian gravity) because the alternative is too computationally expensive to use.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
It's like a sophomore project in universe design class. A way-too-slow hard-coded top speed, lots of localized buffer overflows without proper error handling or anything (Too much mass in one place should at LEAST throw an exception,) particles popping in and out of existence all the time, and the whole thing is held together by duck tape and dark matter. Honestly, I might give this universe a "C"... if I was feeling generous.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
Now maybe they can help me find my keys.
You are welcome on my lawn.
Some explanations of dark matter say that most of the gravitational effects are from dark energy, not condensed into matter. But if dark matter differs from other matter in that it doesn't absorb or emit light, how does dark energy differ from other energy? Energy doesn't absorb or emit light, so how is dark energy different? Unless they mean that it doesn't get absorbed or emitted as light, the way other energy does (ie. photon beams). Without that property it seems rather unlike other energy, enough that it's not really energy.
And if it is dark energy, then where is all the cold, dark info? The next more subtle form of existants.
--
make install -not war
Doesn't matter lead to gravity the way love leads to marriage?
Indeed, once married, gravity doesn't matter any more, with pregnancy, mortgage, kids' school, etc becoming more critical. Gravity starts to matter again closer to retirement age, but then manifests itself more like a burden.
Questions raise, answers kill. Raise questions to stay alive.
first post
Dark post; doesn't matter.
"For example, wouldn't a nebula-sized cloud of free electrons still collapse under their gravitational influence?"
Hell, no. Gravity is orders of magnitude weaker than electrical repulsion. A cloud of electrons would disperse, not coalesce.
Gravity is even weaker than the so-called "weak" force in quantum physics. It is the weakest of all.
Astronomy is a somewhat shaky field - all theories are fundamentally untestable - all you can do is look out at the universe and try to find phenomena that seem to support or counter theory, but in doing so you're making numerous assumptions about what exactly you're looking at to begin with, and assuming it behaves in a manner consistent with other widely accepted but still fundamentally untestable theories. Now that technique is surprisingly effective, but it is vulnerable to flaws in analysis, especially when much analysis is based on something that is known to be inaccurate (Newtonian gravity) because the alternative is too computationally expensive to use.
Makes me feel better about studying Economics
Working ballpoint pens would get used, so they do not get an opportunity to cluster together and reproduce. All working ballpoint pens are, in fact, the sterile offspring of all the non-working ones, just as mules are the sterile working offspring of horses and donkeys...hay fever acting up, please forgive this OT post.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
The top quark has a mass of about 173GeV, which comfortably beats the 125 of the particle detected at CERN.
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
To parahrase Feynmans answer to magnets, how do they work? that was taped long before the question became popular.
At the bottom of every rabbit hole is an explicit assumption. You just have to accept these fundemental assumptions as fact until someone comes along and peels another layer off the onion, assuming there is another layer? You can identify these explicit assumptions fairly easily because they cannot be described by anything more fundemental than themselves therefore all current descriptions of these fundemental properties of the universe are self referencing (or as Feynman put it "cheating"). Dark matter, gravity, spacetime, etc, are examples of these fundemental properties (slashdot challenge: try to come up with a description of a fundemental force or property of the universe that is not self referencing).
Modern physics accepts that we have no idea how these fundemental properties "work", like the universe itself they "just are". This is the "faith" part of science that confuses the hell out of religious and atheistic people alike, science (Natural philososphy) requires the "faith that the real world exists", it answers the proverbial "tree falling in the forest" question with a self-confident - yes! However all is not lost since we do know a hell of a lot about how these fundemental "miricales' behave, so faith in science is not blind faith, it is a faith that's deeply rooted in the utility of the results. ie: we have labeled our best description of this previously unobserved behaviour of the universe as "dark matter" in a way that is consistent with our current understanding of how the universe behaves.
Dark matter is therefore simply the label for the description of what we observe. If it suggest new observations via predictions then great, if it gets them right even better, but even though you have leant a lot more about how it behaves, you still don't actually know what dark matter is ( I particularly like clip for his sly one finger salute to book burning priests at ~2:42).
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
wouldn't all matter collapse into a common gravitational center?
Yes, assuming it's not ripped apart by the expansion of space and assuming there is enough mass in the cloud for gravity to eventually dominate the other forces. Note that some of these filiments are long enough that the two ends are not gavitationally bound (due to the exansion of space).
As I understand it the reason that DM comes in filaments between galaxies rather than seperate blobs has something to do with quantum fluctuations when our observable universe was compresed into a point particle, it also appears that the bulk of the normal matter (galaxy clusters) occurs where these filaments meet (although I don't know of a explaination as to why), the rest of the normal matter (lone galaxies and primordial gas) coincides with the dark matter filaments. In simplistic terms the matter in the universe is arranged like swiss cheese but the space containing the cheese is expanding to rapidly for the cheese to sucumb to gravity and lump together at a central point. Supercomputer models of the 14Gyr evolution of the universe that include dark matter are consistent with observations, models that only use normal matter are not as skillfull in reproducing ALL the observations.
And for all the metaphysics types out there it's been pointed out a map of the universe at the largest scale looks remarkably like the nuron network in a brain
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Is it something like that thing in Star Trek Generations ?
It's estimated that there are 5 times as many dark posts as regular productive ones.
Dark matter is expected to be non-barionic, that means, amongst other things, that it is not formed by atoms (so, no elements as we know them).
Why can't
Maybe, but the gravity is also the only force which works beyond subatomic distances.
Electromagnetism is not short-range. It only seems like it is normally because most materials are electrically neutral.
It's effect is also additive so enough electrons held together would eventually be massive enough to overcome the electromagnetic repulsion (just like protons).
Yes, it's being additive which is why gravity dominates the large-scale structure of the universe (not accounting for dark energy). Electromagnetism likes to cancel out, while gravity likes to build and build.
Weather it's actually possible to condense a cloud of electrons in order for them to exhibit a strong enough gravitational pull, I have no idea.
I don't think so, since the cloud wouldn't exist in the first place. It would disperse long before there was anything like a 'cloud'.
However if you started with something else, like a cloud of hydrogen gas, that could condense, eventually creating a situation where gravity has overcome the electron's repulsion. Something like what our sun will become.
These kinds of objects don't make good dark matter candidates. At least for the majority of the unseen mass, and the observations supporting its existence.
The enemies of Democracy are
The problem is that they've not defined enough properties of dark matter in order for "it's consistent with our model of dark matter" to actually mean much. I guess that gets funding and press interest more quickly than "it's consistent with our current inability to explain everything we see exactly under the widely accepted model".
As there's supposed to be way more invisible stuff then visible stuff, why has nobody seen evidence of visible stuff in orbit around invisible stuff? We've seen plenty of visible stuff in orbit around visible stuff, there should be more visible stuff in orbit around invisible stuff. We've seen plenty of visible stuff smash into and be ripped up by visible stuff - where's the visible stuff that's smashing into invisible stuff, or vice versa? Shouldn't there be more of that happening if there's more invisible stuff than visible stuff? Where is it, if it's so prevalent? With all the properties they've ascribed to it (having way more mass than all the visible stuff in the universe), it should surely be making itself more obvious.
There needs to be an equivalent of profmattstrassler.com for Dark Matter.
Also FatPhil on SoylentNews, id 863