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Dwarf Galaxies Dim Hopes of Dark Matter
An anonymous reader writes Once again, a shadow of a signal that scientists hoped would amplify into conclusive evidence of dark matter has instead flatlined, repeating a maddening refrain in the search for the invisible, omnipresent particles. The Fermi Large Area Telescope (LAT) failed to detect the glow of gamma rays emitted by annihilating dark matter in miniature "dwarf" galaxies that orbit the Milky Way, scientists reported Friday at a meeting in Nagoya, Japan. The hint of such a glow showed up in a Fermi analysis last year, but the statistical bump disappeared as more data accumulated. "We were obviously somewhat disappointed not to see a signal," said Matthew Wood, a postdoctoral researcher at Stanford University who was centrally involved the Fermi-LAT collaboration's new analysis, in an email.
or can know....or something like that.
Dark Matter is the Aether of the 21st century. Eventually we'll stop wasting money on finding it.
I'm an American. I love this country and the freedoms that we used to have.
i think at some point some scientists somewhere will work out that the statistical evidence is growing to show, more and more, that dark matter *doesn't* exist...
WTF
I love it when science can't explain something yet, it means we have so much more to learn.
The Dark Matter is still there, as something (we don't know what). This doesn't "dim" the existence of DM as an effect* at all. What this does is (again) dim some faint hopes it might be WIMPS. It doesn't constrain other models / theories at all.
* : even if the DM is MOND, or some other gravity correction, it might not be matter, but the effect would still exist.
There has never, ever, ever been any evidence at all that dark matter exists. It's all just math and for the math to be correct, us on Earth have to be able to calculate the total mass and energy in the entire universe. We're only off by like 10:1 too at last count. So instead of calling it invisible and omnipresent, how about the more accurate invisible and onmi-non-existant.
The National Debt is made of dark matter. Eventually, it fades into the background and we don't even notice it.
Dark matter is made from all the jokes that God doesn't think are funny.
If you want to be technical about it, you are creating an excluded middle.
Thinking that the current search for dark matter is wasted effort hardly makes you anti science. It just means you don't like a particular line of research. I happen to be very pro physics research but very anti spending on ever larger accelerators. While they do get results we haven't been getting very much in spinoff from them for a very long time.
Dark Matter and Dark Energy are not terms that should conjure up weirdness in your mind. Not at this point, anyway.
Neither concept has a shred of evidence behind it indicating that anything exotic is going on. If you really want a good handle on the terms, just think of them as "We hope some sources of energy and matter we can't detect are out there because otherwise, the math behind our hypotheses doesn't work."
It's a limitation of trying to figure out what's going on incredible distances -- and times -- from us with a combination of barely functional tools, our (decent, I'm guessing) grasp of science, and the participant's intuitions.
I've fallen off your lawn, and I can't get up.
Dark matter is like the old ideas of phlogiston and the luminiferous ether of previous centuries. There is no such thing. The problem is that current physics lacks a proper understanding of gravity. Physicists will eventually find that the gravitational constant is not a constant and that it varies according to scale and time. Once that is realized there will no longer be a need to invoke the concept of dark matter to explain what holds galaxies together despite their rotation.
There is no dark matter... it's a glitch in the machine.
That's not a bad thing; a glitch can be exploited.
It is very easy to imagine models for Dark Matter where the DM cannot annihilate with itself. In such cases there are only two ways to detect it: create it in high energy collisions such as those at the LHC or detect it bouncing off an atomic nucleus in extremely sensitive experiments placed deep underground to shield them from cosmic rays. The fact that there is no evidence of annihilating Dark Matter does not "dim hopes of Dark Matter" it just dims hopes of one particular class of model of Dark Matter.
If the LHC sees nothing in the next few years though it does tell us something: Dark Matter is unlikely to be a a massive particle which interacts with matter via the weak force. At LHC energies we can pretty-much exclude the mass range consistent with thermal production in the Big Bang for this class of particle. There are ways around this e.g. exotic production mechanisms or multiple types of particle contributing to Dark Matter but the simplest models for weak particles will be gone and axions might start to look even more attractive as an explanation.
what dark matter is, it's every species out there that reached the stage of 3D printing eventually 3D printed so much free stuff that you can detect its mass.
Exactly. The observations do not fit the theory, therefore the overarching theory is wrong - period. It NEVER works the other way around. Go back to the drawing board and conjure up something else.
This is what happens when "scientists" have the produce something interesting in order to keep someone else's money flowing into their pockets.
It really boggles my mind that the guys studying this stuff haven't come to the conclusion that the matter "missing from universe" that they are trying to associate with Dark Matter is more than likely brown dwarfs or dense material with just can't detect yet from super nova explosions. WTF IS WRONG WITH YOU PEOPLE!
It doesn't matter what you call it ... declining or dilution ... the end result is fewer women in CS career fields than men. The effect is less a less robust CS field and the resulting negatives that come along with a technology field operating with blinders.
Why are scientists obsessed with finding the most exotic explanation of Dark Matter without first exhausting the more prosaic explanations? It is Occam's Razor upside down. I think that the reason is there there is a Nobel Prize and fame if Dark Matter turns out to be a particle, but there is no glory if it turns out to be something more ordinary such as neutral hydrogen, dust, etc. Even a modification of Newtonian laws at a distance to explain Dark Matter is not exotic enough.....so we have to endure Crackpot Cosmology Theory (CCT) of the week from here to eternity...
Don't know much about physics, but Newton's laws of motion were good and still work on a small scale for most practical purposes. Then we had the theories of general and special relativity, which work on larger scales and describe spacetime. Further we have quantum field theory, which describes interactions at an extremely small scale and apparently has yet to be unified with the G/S theories of relativity. The lack of unification leads me to believe that we're either too stupid to discover the missing link or that one or both theories are inaccurate. Now that our observable universe is pretty damn huge, a larger sample size to test our various theories against, it doesn't surprise me that things don't add up. There could be dark matter/energy, other dimensions/universes bumping into ours, a godlike noncorporeal alien race using quantum teleportation as its neural network and galaxies as its body, etc., but if I had to put good money on it I'd venture that our theories are wrong. Until current "working" theories can at least be unified, I'd hold off proposing things like the majority of all matter/energy in the universe not being directly observable. Errors on a small scale are negligible, but when applied at the insane scale of the universe they can't be ignored. Even if dark matter/energy do exist, our theories are probably still wrong.
Buy your next Linux PC at eightvirtues.com
Of old in the era of exploration in the 16th and 17th Centuries for mariners on the open sea. That astronomers let themselves be taken by such silliness will rank up there with canals on mars and epicycles in terms of erroneousness.
As for what can explain the rotational nature of galaxies it's rather simple. We know that galaxies form clusters, superclusters, and filaments that extend for millions to billions of light years which naturally evolve from intergalactic and interstellar plasma and matter pushed from stars that we can observe on a daily basis among most stars including our own. And these stars, galaxies, and galactic clusters align along and are entrained by electromagnetic fields that all stars and galaxies generate. This can and is observed on a daily basis in telescopes around the world.
And this is a far simpler and more logical theory than hypothesizing imaginary matter that has never been observed.
I don't know... I kind of like the fact that the universe is still such a mystery to us. With the large hadron collider there was almost a sense of let down that nothing exotic or unexpected appeared. That everything went according to our models.
Of course it flat-lined, they were using the Fermi Large Area Telescope (FLAT)!
No problem.
Just present a model that works with the observational data it and it will be gone.
I came here hoping for a si-fi version of Dwarf Fortress...
As early as the 1670s, Newton used the idea of aether to help match observations to strict mechanical rules of his physics.
"The motion of light was a long standing investigation in physics for hundreds of years before the 20th century."
Ether theorists: Newton, Robert Boyle, Christiaan Huygens, Faraday, Lorentz, James Clerk Maxwell, Poincare...
It is noteworthy that, despite it being impossible to prove a negative, the ether has supposedly been disproven. So why does Wikipedia add a question mark to that section's title?
My own theory of the ether, gravity and QM.
I come here for the love
African-American matter is the correct term.
"Little People" Galaxies
That sounds like it'd be Fisher-Price's attempt to cash in on the popularity of LEGO film-to-game adaptations and The LEGO Movie.
There is no doubt that there is a dark matter "effect", it is just that we don't really know we will every find a particle that is "Dark Matter". I kind of dislike the name for that reason, maybe scientist are affected by this but your common layman seem to think one day we will have bottles full of "Dark Matter" we can use in some future technology. We simply know very little about what is causing the dark matter effect and we have much more knowledge about what it isn't than what is might be. The key is to keep an open mind about what we might be looking for.
That was the first thing they thought up. Turned out that was wrong, and something weirder is going on.
If you look for the golfball particles, perhaps you can find the Dorf galaxies?
Tracy Johnson
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BT
Why are we chasing dark matter (and dark energy while we are at it)? If you have studied the history of science it is pretty obvious that these two terms are essentially the same as Copernicus' epicycles: a hack to make a failing hypothesis work for a while. When scientists come up with things that are:
a) undetectable/unverifiable
b) arbitrarily designed to fit the error margin between theory and observed fact
c) like something a sci-fi author is about to base a whole book series on
you can pretty much take it to the bank that not only is this newly named "phenomena" a complete fabrication, but that the theory that required it is so far from the truth that no minor tweak would get even close to the target.
Seriously, nobody spotted that according to this theory all detectable matter accounts for only 10% of the mass of the universe. i.e. our error margin is 10x (not 0.1% or even 10%, but 1000%). The noise to signal ratio is: there is no signal!
Never mind being in the ballpark, current theory hasn't even left home, it may be in the basement tinkering with the boiler or something, because it certainly hasn't even seen the ballpark!