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- mykos, on 10/11/2007, -9/+57Or hardcore porn.
- jsbarone, on 10/11/2007, -0/+26Well, considering that Dark Matter accounts for 80%+ of the matter/gravity in the universe, and that it's thought to be all that's holding our galaxy (and all galaxies) together, I'd be willing to bet that yes, it does matter. If Dark Matter doesn't exist, then Science needs to rewrite the laws of physics, because stuff just isn't working the way it's supposed to.
- mykos, on 10/11/2007, -2/+28No need to announce an announcement. Just tell us already!
- chrisbosh123, on 10/11/2007, -6/+25"ring of dark matter" sounds like a lord of the rings trilogy
- effinboy, on 10/11/2007, -2/+12Terrorists!
- Falcorian, on 10/11/2007, -2/+10Not Science's fault that Dark Matter is the best fit to observations.
As CarmelBuck posted a few months ago on slashdot (http://science.slashdot.org/comments.pl?sid=215548&cid=17502630) (Got to make sure I attribute!)
"So let's start at the beginning, shall we? Galaxy rotation curves indicate that there is more mass in galaxies than would be inferred from the luminous matter. How do we know that it's not clouds of cold gas? Because that's ruled out by 21cm observations and by studying the absorption spectra of extragalactic objects. How do know that it's not clouds of hot gas? Becasue that's ruled out by UV and X-ray observations. How do we know that it's not brown dwarfs and black holes? Because that's ruled out by microlensing surveys.
Now, studies of galaxy dispersion velocities in clusters indicates that there's more mass in galaxy clusters than than would be inferred from the galaxies themselves, plus the intracluster medium which is observed in the X-ray. This is verified to high accuracy (i.e., the estimates of the total cluster mass are in close agreement) by hydrostatic X-ray mass measurements and by weak lensing observations. How do we know that it's not clouds of cold gas? Because that couldn't coexist with the hot gas, and because the dark matter spatial distributions are clearly different from the gas distributions. How do we know that it's not clouds of hot gas? See "intracluster medium" above. How do we know that it's not brown dwarfs and black holes? Because there's no mechanism for moving large numbers of objects out of the galaxies into the ICM (there are some intracluster stars, yes, but relatively very few--and the number of those gives us hints as to the number of non-luminous objects similarly ejected). How do we know that it's not neutrinos? Because neutrinos are experimentally shown to be too light and too fast, and cosmological constraints show that too few would have been produced in the Big Bang.
Now, studies of cosmological structure formation indicate that the size and number of galaxy clusters in the universe are not consistent with what would be expected given an all-baryonic universe. How do we know that...er...well, that's that. Cold collisionless dark matter is required to make the simulations work.
How do we know that modified gravity isn't the answer? See multiple independent lines of evidence above. There are no theories of modified gravity that come even close to explaining all of the above. The MOND people cheerfully acknowledge this, even if their advocates on Slashdot don't.
Look, the history of physics is replete with things whose existence was inferred long before they could be directly observed--neutrinos, quarks, atoms themselves, and much, much more. It's simply asinine to suggest that "we haven't directly measured it" means "it doesn't exist". Heck, we only really "see" subatomic particles because of the photons given off when they interact with one thing or another--"seeing" dark matter via measurements of its gravitational effects is hardly less direct.
And we'll just ignore the nonsensical "fitting facts to the data". The bottom line is, there are multiple, independent lines of evidence that dark matter exists, and that it is non-baryonic. Uninformed posters on Slashdot can pat themselves on the back for their intelligence as much as they want, but they're only fooling themselves."
Or in short: Go read up on Dark Matter. It's the leading theory for a reason. - rwiser, on 10/11/2007, -0/+7To clarify:
-Dark matter (if it exists, and it may not) is completely different than aether.
-We don't seem to be able to actually see dark matter, only the effect it has on matter.
-Einstein may have liked this. But only because finding new cool things about the universe is fun.
-Although astronomers before Einstein showed very strongly, if not proved the absence of ether, Einstein is given the major credit for disproving the ether hypothesis. Here is a nice link about that http://itis.volta.alessandria.it/episteme/ep3-24.htm - laplacian, on 10/11/2007, -0/+5NASA already found evidence of dark matter with Chandra: http://www.nasa.gov/vision/universe/starsgalaxies/dark_matter_proven.html
- Nocterminus, on 10/11/2007, -0/+4I can't help thinking of this quote:
"There are more things in heaven and earth, Horatio, Than are dreamt of in your philosophy"
William Shakespeare, "Hamlet", Act 1 scene 5 - Jugalator, on 10/11/2007, -0/+3"Now the telescope named for Hubble proves the existence of dark matter, which in essence COULD very well be that all-pervading aether under an assumed identity. Would not an aether by any other name still smell as sweet?"
Dark matter is the kind of matter that some believe have already been observed indirectly from gravitational lensing effects. It is called "dark" because it does not emit light and is therefore hard to see. Current models need dark matter to explain why the matter clump together to form galaxies, because the models don't say that they should, given the visible matter alone. Aether is a bit weird on the other hand, depending on your POV, may mean anything between a new form of matter believed in before the light particle/wave duality was formulated by Einstein, to a mysterious driving force of life. Aether is kind of unrelated to particles with mass, as the idea is behind dark matter. - MikeCampo, on 10/11/2007, -0/+3How original.
- GeneralKickass, on 10/11/2007, -2/+4But what the F is dark matter, you ask?
Matter of unknown composition that does not emit or reflect enough electromagnetic radiation to be observed directly, but whose presence can be inferred from gravitational effects on visible matter.
http://en.wikipedia.org/wiki/Dark_matter
(I didn't know either) - HayString, on 10/11/2007, -5/+7Burried for having "Hubble" in the title but not having a single picture.
- Falcorian, on 10/11/2007, -0/+1Close, there has been strong evidence for it found before, See: http://en.wikipedia.org/wiki/Bullet_cluster
Ok, I admit it, not really that close at all. - seattlephantom, on 10/11/2007, -2/+3I find this topic very interesting, but I think I would hold off until the press conference when we get photos to actually look at and discuss.
- shovel24, on 10/11/2007, -0/+1It's 'shopped.. no wait, it's a CG film, no.. wait, it's a hallucination, no, MASS hallucination!!
- triskaid, on 10/11/2007, -0/+1can someone tell me why it isn't just... dirt? rocks, planets, etc? we can't see non-luminous stuff. our planet is non-luminous. I know it's reflects some light but our best telescopes still have problems seeing planets far away from us, I'm talking here about relatively short distances, like within our own solar system and nearby solar systems. The term "dark matter" is so mysterious but maybe that's all it is. matter that we don't see because all we can see is the stuff that is bright. we can see when stars orbits act strangely and that gives us some information about what's going on with them, but if you have a star, and then two planets of the same size orbiting around that star at the same distance from it and speed, would you notice anything strange about that star's movement? You probably would, but all I'm saying is that the movement of a star may not bely exactly how much mass is orbiting around it since mass distributed evenly around it may sort of cancel out other matter orbiting around the other side. what's to say that there is some unbelievably insanely large black hole so far away from us that no evidence from its existence has ever reached the earth? I just find this mystery annoying because I think the answer is going to turn out less exotic and mysterious than discussions of it seem to imply.
- Jugalator, on 10/11/2007, -0/+1It's theorized the density of dark matter disappear more quickly than dark energy.
http://en.wikipedia.org/wiki/Equation_of_State_(Cosmology) - BadAstronomer, on 10/11/2007, -0/+1The press conference is in a few minutes. I have researched the science here, and it does look pretty cool. I'll have a blog entry up about it promptly at 10:00 a.m. Pacific time. http://www.badastronomy.com.
- ShatteredBlade, on 10/11/2007, -1/+1Rewriting physics would vastly change the understanding, of pretty much... everything. And they say this is the strongest evidence found so far, this isn't the actual thing. There's still a measure of error in this.
- Pocker09, on 10/11/2007, -2/+1Futurama FTW!!
- EdgarVerona, on 10/11/2007, -2/+1Damn, impressive. I kind of did a double-take when I saw the title.
Does that mean that, indeed, the universe will collapse back on itself instead of expanding in the "heat death of the universe" scenario? I haven't read anything about dark matter for a while, but I remember that scientists speculated that the existence of dark matter would be the only thing that could result in a recollapsing universe (to set off a future big bang event) or something like that. - MasterFunk, on 10/11/2007, -2/+1A researcher was quoted saying, "I don't know what it was, this one area just seemed a little darker than the rest of space."
- dawtips, on 10/11/2007, -4/+2It's a Supergate you morons
- stevealford, on 10/11/2007, -8/+6So we abandon the concept of the aether and static universe when Hubble's observed red shift confirmed universal expansion... and we went with the "vacuum of space" instead of aether. Now the telescope named for Hubble proves the existence of dark matter, which in essence COULD very well be that all-pervading aether under an assumed identity. Would not an aether by any other name still smell as sweet?
Einstein would love this... bringing back the theories of the early 20th century under new names so you aren't called a retard because "everyone knows there's no aether." Now it's just "a mysterious form of energy that we can't fully quantify and it pervades all of space." Tell someone you believe in aether and they'll laugh at you, but tell them you believe dark matter exists and they'll think you're brilliant... if only they knew that they're the same side of the same coin, just new terminology. - stevealford, on 10/11/2007, -2/+0I don't know why you guys are telling me to learn more about dark matter and then modding down... perhaps you should learn more about aether theories, because it's actually pretty complex and there isn't just ONE interpretation. Many aether theories relate directly to dark matter theories, especially quantum effects on particles travelling through the aether or region of high dark matter density. Like I said, you're called a retard if you talk about aether (you proved it by modding me down), but the point of science is that a model can be revised, and it seems that dark matter theory is an in-depth revision of aether theories, just under a new name. The fact that you couldn't directly detect the aether was a big reason for discarding it, yet is one of the main arguments FOR dark matter. The empirical effects of dark matter can be detected, but it cannot be fully quantified and emits no light, therefore it's DARK matter... yet that doesn't mean it doesn't fit the description of aether.
If a photon travels slower than usual or at a strange angle through a region of seemingly empty space today, you'd say that its path was affected by dark matter's gravitation or other quantum effects on anything travelling through that region. How is that different than saying that the aether in that region is shaped differently because of a lack of mass? The only difference is that you're predisposed to think anything with the word aether is ridiculous... but it's the exact same thing as saying that the entire universe is filled with dark matter (the current model) with very high concentrations in empty spaces and low concentrations where there's regular matter. - stevealford, on 10/11/2007, -2/+0Jugalator, saying that aether is unrelated to particles with mass is the same thing as saying that the ocean has nothing to do with the fish that live in it. According to the theory, aether is the medium through which the galaxies move, therefore it is made up of particles itself, not just an empty vacuum. That's the SAME as the current dark matter model, which says that dark matter permeates the entire universe with different concentration levels based on the amount of regular matter in the vicinity. Same model, different name.
- zaldoe, on 10/11/2007, -2/+0site seems to be down
- inactive, on 10/11/2007, -9/+2Pics or it didn't happen! (well.. until they release the pics..)
- LordofShadows, on 10/11/2007, -9/+2About as much as luminiferous aether.
- jonpotz, on 10/11/2007, -9/+1OLD NEWS...Dark matter has already been discovered, it's called the Bush administration.
- allenu, on 10/11/2007, -13/+3I immediately thought of goatse.cx when I read "ring of dark matter".
- m00nb34m, on 10/11/2007, -14/+3Come on...does dark really matter?
- futureisours, on 10/11/2007, -15/+3Thank you for that funny, but sick comment.
- coolian, on 10/11/2007, -14/+1Urgh. Bukkake.
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