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Dark Matter Filament Finally Found 190

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."
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Dark Matter Filament Finally Found

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  • by Lukano ( 50323 ) on Thursday July 05, 2012 @08:33PM (#40558995)

    Yeah this post didn't deserve a downmod. It was an applicable use of pop-culture humor.

  • by Anonymous Coward on Thursday July 05, 2012 @10:02PM (#40559441)

    You must be a Fox News watcher.

    Because you are so fucking arrogant as to think that you who obviously don't know shit about cosmology, astronomy, or astrophysics, would think that you know better than people who have been working for years, some their entire lifetime. Seriously if you had one fucking class on the subject you would know that cold regular matter absorbs light, so it can still be directly observed like a shadow.

    So how about stop assuming that you know more about physics than the physicists, and try and learn something?

  • by Immerman ( 2627577 ) on Thursday July 05, 2012 @10:30PM (#40559603)

    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.

  • by shaitand ( 626655 ) on Friday July 06, 2012 @03:10AM (#40561015) Journal

    "Well, on the "prove/disprove" front, all this has done is fail to disprove the existence of dark matter. There's a difference between that and actually proving its existence."

    Science doesn't prove things exist or don't exist. The only thing science does is collect objective observations and come up with math that predicts what future observations will be given a set of conditions. Someone also makes up an interesting story to goes along with the math but aside from being consistent with the math the story (hypothesis/theory) doesn't really matter that much. Unlike the story, future observations can't break the math (although they can supercede it). Just ask Mr. Newton.

  • by TapeCutter ( 624760 ) on Friday July 06, 2012 @05:48AM (#40561637) Journal
    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).
  • Re:Dark Post (Score:5, Insightful)

    by Jellodyne ( 1876378 ) on Friday July 06, 2012 @09:54AM (#40563217)
    It's estimated that there are 5 times as many dark posts as regular productive ones.

COMPASS [for the CDC-6000 series] is the sort of assembler one expects from a corporation whose president codes in octal. -- J.N. Gray