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Two Big Dark Matter Experiments Gain US Support

Soulskill posted about 6 months ago | from the stuff-that-dark-matters dept.

Space 37

Graculus writes: The Department of Energy and the National Science Foundation announced on Friday that they will try to fund two major experiments to detect particles of the mysterious dark matter whose gravity binds the galaxies instead of just one. The decision allays fears that the funding agencies could afford only one experiment to continue the search for so-called weakly interacting massive particles, or WIMPs.

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Wimps (0)

Anonymous Coward | about 6 months ago | (#47470451)

Not in th U.S.!

Pronounced "Mur Ick Ah" (1)

xxxJonBoyxxx (565205) | about 6 months ago | (#47472127)

Pronounced "Mur Ick Ah"

Re:Wimps (0)

Anonymous Coward | about 6 months ago | (#47474435)

Nope, only MACHO's over there.

Re:Wimps (0)

Anonymous Coward | about 6 months ago | (#47474505)

I mean MACHOs.

Of course it won't be settled then (0)

i kan reed (749298) | about 6 months ago | (#47470463)

We'll have more information about the gravity attributes and locations of dark matter, but no deeper insight into how it connects to the physics we DO understand. I'm not trying to be a naysayer, I'm positively thrilled that we're going to find out what we can, but until we can get up close, and determine exactly what ways dark matter interacts with all other forces, its underlying nature will be a bit mysterious.

Re:Of course it won't be settled then (3, Insightful)

joh (27088) | about 6 months ago | (#47470537)

"A bit mysterious" is the understatement of the day... Still, it's one of the very few actual observable things that could further some fundamental new understanding of physics.

Re:Of course it won't be settled then (0)

Anonymous Coward | about 6 months ago | (#47471509)

Did those experiments "attract" US support? If so then maybe the experiments are dark matter and the experimentalists are dark agents of subversion!!

Re:Of course it won't be settled then (0)

Anonymous Coward | about 6 months ago | (#47471781)

They could find out everything about it and humanity would be no further advanced that if they had spent the whole time debating how many angels could dance on the head of a pin!!! Seriously, why can't they spend time and energy doing something, anything, useful like figuring out how aerogel can be produced cheaply and efficiently? Is something practical just too much to ask?

I don't see what you are saying (4, Insightful)

pavon (30274) | about 6 months ago | (#47470545)

We'll have more information about the gravity attributes and locations of dark matter,

Both of these experiments aim to detect collisions of dark matter particles with their respective detectors, and if found give an estimate of the particles energy. Neither are astronomical surveys that would tell us anything about the gravitational properties or distribution of dark matter.

Re:I don't see what you are saying (2)

lgw (121541) | about 6 months ago | (#47470913)

Clearly, we'd know something about the distribution of dark matter if the detector encountered a particle: 1 particle, right here. That may sound like a joke, but we know so little that any sort of estimate of dark matter density near Earth would tell us something interesting about its distribution (presumably affected only by gravity, but we don't really know beyond "not affected by EM").

Huh? (2, Insightful)

Anonymous Coward | about 6 months ago | (#47470677)

What are you TALKING about? Your username may be "i kan reed" but it seems you did not choose to read the article.

Re:Huh? (1)

Anonymous Coward | about 6 months ago | (#47470739)

You must be new here.

Nothing to see here (0)

Anonymous Coward | about 6 months ago | (#47472165)

He (or she) is a well-known troll who has something controversial and idiotic to say on every article. Set them to -5 and move on.

Re:Of course it won't be settled then (1)

MightyMartian (840721) | about 6 months ago | (#47470693)

The place we're ultimately going to learn about dark matter is likely to be a combination of specialized detectors, but also terrestrial particle accelerators. Dark matter, whatever it is, may suggest the physics beyond the Standard Model that physicists so hunger to finally get some evidence of.

Thank God. I thought they might (0)

Anonymous Coward | about 6 months ago | (#47470495)

Try and scrape up some money to invade the Maldives.

Found some! (1)

Anonymous Coward | about 6 months ago | (#47470571)

Scanners are detecting a large formation of WIMPS on slashdot.

Dark Matter = Phlogiston (0)

DogShoes (149641) | about 6 months ago | (#47470601)

When your theory of the Universe doesn't work, just make shit up until it does.

Re:Dark Matter = Phlogiston (1)

MightyMartian (840721) | about 6 months ago | (#47470701)

No, you come up with theories, and then you attempt to demonstrate their validity, or disprove them.

Re:Dark Matter = Phlogiston (0)

Anonymous Coward | about 6 months ago | (#47471799)

Like your theory? ;} This is what theories are meant to be for.. you know, induction/deduction..

Re:Dark Matter = Phlogiston (1)

gtall (79522) | about 6 months ago | (#47473625)

Phlogiston gets a bad rap as a failed theory. However, at the time, we were attempting to make sense out a very confusing physical world. Science always makes shit up, it is called creativity. However, Science also cleaves off the parts that do not hold up.

Einstein made up his entire gravitational theory. The equations did not exist in some Platonic universe waiting for him to trip over them. He created a mathematical world that could be tested against reality.

Quantum theory is an interesting case. It doesn't really explain anything, but it has damn good numbers and predictive value. It's something we made up. It is well-made, but in a philosophical sense, it isn't really a theory if the intent of a theory it to help explain the inner workings of some phenomenon.

Re:Dark Matter = Phlogiston (0)

Anonymous Coward | about 6 months ago | (#47504917)

Quantum theory is an interesting case. It doesn't really explain anything

Sure it does. Quantum Field Theory (QFT) explains very well that there are several relativistic fields that have excitations that take discrete natural-numbered values rather than real values, that any such excitation is *exactly the same* as any excitation with the same discrete values, that these excitations can be considered as "particle content" of the fields or treated as wavelike excitations, that there are interactions among the particle content of the various fields that are the same in any situation, and that any set of inertial observers can agree on the time-wise ordering of these interactions with respect to one another. The Standard Model is a paradigm of QFT, and has subsumed some of the discoveries from older (sometimes non-relativistic) quantum theories such as quantum electrodynamics.

The Standard Model explains very well why bound and free electrons behave differently, why unbound neutrons decay, why hot objects radiate particular spectrums of electromagnetic radiation, and many other things. It also explains (via Noether's theorem) why there are conservation laws like the conservation of energy or the conservation of linear or angular momentum.

The Standard Model does not explain why the indiviual particle content of each of its fields has the particular masses that all observers measure, nor does it give many clues for several other parameters which have been discovered empirically. For example, it offers no insight into why the electric charge of a proton and a positron are identical within the limit of our ability to measure. It also doesn't explain gravitation.

However, quantum theory does provide some insight into gravitation -- there are active quantum gravity programmes, and most cosmologists reasonably think that gravitation eventually will be modellable using quantum theory rather than the non-quantum theory of General Relativity. Such a description will describe -- and explain -- the behaviour of matter and energy in and near extremely dense objects such as black holes and the early universe, even if it includes free parameters which must be put in "by hand" based on empirical evidence rather than being manifestly obvious from the theory itself.

Just because the explanatory power of the most fundamental (and most successful) physical theories we have available today is incomplete does not mean that they provide no explanation for why things in nature behave the way they do. It's not *just* predictions based on an initial value surface.

Re:Dark Matter = Phlogiston (1)

dissy (172727) | about 6 months ago | (#47474729)

When your theory of the Universe doesn't work, just make shit up until it does.

You mean like you just did?

If you believe dark matter does not exist, then why do we see it? Why do we also see it affecting other things? What in your limited opinion is causing that?

If you are attempting to claim an existing force or particle is causing those effects, then why does that violate the known definitions of all forces and particles known?

Why exactly do you believe a force that has characteristics not matching any existing forces would be anything other than a new force?

If you want to claim this force is an existing one, the burden of proof as to why it doesn't match up to any known force yet somehow is one of those forces is all on your head buddy.

Either explain up, or stop bitching about people who know what they are doing that claim it is a new force.

Re:Dark Matter = Phlogiston (0)

DogShoes (149641) | about 6 months ago | (#47477621)

I don't need to explain anything. Dark matter is bullshit and you know it, or you wouldn't flame out on a nobody like me.

BTW: Bitching? I wrote one sentence. You go girl!

Now go away before I point a Dark Energy Ray-gun at your screen and collapse it into black hole that eats Russia, Ooops. Too late.

It's about time ... (1)

CaptainDork (3678879) | about 6 months ago | (#47471129)

... that America participates in science experiments on American soil.

We passed on Waxahachie, Tex. [scientificamerican.com] and many of the world's premier scientists are having coffee at the LHC. America could have detected the Higgs boson.

Hopefully, we'll get lucky and find something worth contributing regarding dark matter.

Then, America would be one of the cool peeps.

Re:It's about time ... (1)

Rockoon (1252108) | about 6 months ago | (#47472683)

I doubt that even if we built the SSC that we would have found the Higgs before de-funding it.

Consider the amount of data the LHC needs to collect to observe the Higgs and then consider what sort of technology was available in the early 1990s. The LHC requires the worlds largest ever computing grid to process the data it collects, and it generates a whopping 300 gigaBYTES per second.

Good luck with that with technology from 20 years ago. The best CPU's from 1994 were the Alpha 21064 [wikipedia.org] which peaked out at 300 MIPS (modern desktop chips peak out at well over 100000 MIPS), and you dont even want to consider actual bandwidth and storage.

The SSC could not match the LHC even though the SSC was to be a more powerful accelerator.

Re:It's about time ... (1)

CaptainDork (3678879) | about 6 months ago | (#47473789)

While your statements are correct, for fair comparison I think we should grant growth predictions to SSC that happened at LHC.

It's true. (0)

Anonymous Coward | about 6 months ago | (#47471275)

The Department of Energy and the National Science Foundation announced on Friday.... I guess I know where not to look for current news. ./ is now leading the pack of followers of news past.

Re:It's true. (1)

HybridST (894157) | about 6 months ago | (#47474363)

/. Is a news aggregator, not a primary source.

If course it does! (1)

sdack (601542) | about 6 months ago | (#47471531)

Hey, yo, why do two experiments? We all know dark matter. I thought we left that racism shit behind.

Why not an explanation that doesn't require Dark M (0)

Anonymous Coward | about 6 months ago | (#47472103)


Dark Matter == Measurement Uncertainty? (0)

Irate Engineer (2814313) | about 6 months ago | (#47472153)

I won't claim to be a astrophysicist, but "dark matter" strikes me as similar to the "ether" posited 120-odd years ago. I'm curious to know if dark matter is simply an artifact of observational resolution, or is it really and truly a difference between accurate observation and theory.

In particle accelerators, the Standard Model seems to be holding up well. Versus astronomical observations, not so much. In my ignorance, I wonder if this is just due to the uncertainty in observations.

Anybody want to clue me in on the state of affairs, with my thanks?

Re:Dark Matter == Measurement Uncertainty? (2, Informative)

Anonymous Coward | about 6 months ago | (#47472269)

Well, you can look at error bars on galaxy rotation curve results like this [nd.edu] , which is old enough to end up in an intro cosmology course. If it were just visible matter, it would be the curve labeled "disk". If you add the curve "halo" you get the total, with the small measurement error bars shown. Surveys like this [lanl.gov] show the limits of such halos being just from compact but dark objects.

Re:Dark Matter == Measurement Uncertainty? (2)

MrFlibbs (945469) | about 6 months ago | (#47473911)

There are several data sets that suggest the presence of Dark Matter:
    1) Orbital velocities of galaxies within a cluster are too high -- the galaxies should fly apart unless much more mass is present.
    2) Observed rotational velocities of edge-on galaxies are wrong: stars near the edge rotate too fast -- unless there's a cloud of mass beyond the observed disk.
    3) Gravitational lensing effects are too strong for the observed mass of the lensing clusters.
    4) Numerical simulations modeling the Big Bang up to present times work well only if Dark Matter is assumed.

There may be other data sets, but these are the ones that were presented in the Coursera class I took last year titled, "Galaxies and Cosmology".

Re:Dark Matter == Measurement Uncertainty? (2)

painandgreed (692585) | about 6 months ago | (#47476857)

And on top of that, every other explaination that people have come up with to explain those data sets has failed.

MOND - the idea that gravity has some extra factor that kicks in on galactic scale has yet to provide even a hypothetical answer to be tested. Last I heard, it gets complicated so fast that they haven't even been able to produce a hypothetical gravitational equation that would explain orbital velocities of galaxies let alone the other observed data.

That the extra matter is out there in more mundane forms such as dim stars or jupiter like orphan planets has been tested since they first started seeing these obeservations, and all tests so far have shown that if that was the case, they should be able top detect it but haven't.

Somebody once made a comment on /. about just because we put out cat food and it is disappearing, it doesn't mean there is a cat in the house that nobody has seen. However, at this point, the cat food is being eaten, the litter box is being used, something is playing with the cat toys, and if you knock on the walls, you can hear something go "meow". It still may not be the case that there is a cat we've never seen living in the house, but if so, the new answer is much stranger and more complicated.

waste of money (0)

slashmydots (2189826) | about 6 months ago | (#47472249)

Every dark matter detection experiment ever performed has suggested it doesn't exist. The proof that it does exist requires that we accurately know how much mass is in the universe, which we absolutely do not. The money should be spent on developing fusion, not testing for dark matter. They might as well fund a search for bigfoot.

Re:waste of money (1)

Anonymous Coward | about 6 months ago | (#47472635)

Why didn't you just say "I know nothing about science and refuse to learn"? It would be shorter and more honest.

fears (0)

Anonymous Coward | about 6 months ago | (#47473307)

but Fear leads to the Dark Side, so we should keep them up -not allay them!

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