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NASA and DoE Team On Dark Energy Research

timothy posted more than 5 years ago | from the what's-the-opposite-of-illuminati? dept.

NASA 106

Roland Piquepaille writes "NASA and the U.S. Department of Energy have teamed up to operate the future Joint Dark Energy Mission. As you probably know, recent astronomical measurements have showed that about 72% of the total energy in the universe is dark energy, even if scientists don't know much about it, but speculate that it is present almost since the beginning of our Universe more than 13 billion years ago. The JDEM 'mission will make precise measurements of the expansion rate of the universe to understand how this rate has changed with time. These measurements will yield vital clues about the nature of dark energy.' The launch of a spacecraft for the JDEM mission is not planned before 2015."

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Need a better marketing department (3, Insightful)

MosesJones (55544) | more than 5 years ago | (#25914681)

Come on.... "Dark Energy" this should have everyone wearing some form of mask and a black uniform with just a simple white spark on it or something. We complain about not getting kids into science and then when we get something with one of the coolest sounding names around we make it into something dull and boring.

"Dark Energy has been around for 13 billion years but no-one has been able to harness it. Do you have what it takes to join the Legion of Dark Scientists?"

Re:Need a better marketing department (1)

iphone luvs ssh (1397163) | more than 5 years ago | (#25914995)

Dude, this has been around for ages... didn't Enron market this??

Re:Need a better marketing department (3, Funny)

Andr T. (1006215) | more than 5 years ago | (#25915005)

The mascot could be Darth Vader!

Mechanical voice:

- Come join us understand the real nature of the Universe. Together we will understand the deepest secrets of matter and energy...

Darth Vader approaches a group of scientists wearing white clothes, looking at a telescope and talking to each other.

- And you can be sure the smartest minds of the planet will be with you in this journey. May the energy, dark and bright, be with you, my friend.

Re:Need a better marketing department (0)

Anonymous Coward | more than 5 years ago | (#25918045)

- And you can be sure the smartest minds of the planet will be with you in this journey. May the energy, dark and bright, be with you, my friend.

God. I want the drugs those guys who modded you funny were on.

Re:Need a better marketing department (1)

ikkonoishi (674762) | more than 5 years ago | (#25916249)

They [wikia.com] have already taken over. Grab a crowbar and follow Freeman. He is our only hope.

Oblig. Simpsons (3, Funny)

SpectreBlofeld (886224) | more than 5 years ago | (#25916781)

Lindsay: Yes. For example, no one was showing up for jury
                duty, so we made the experience more exciting by
                synergizing it with his comic book collection.

                [cut to Moe's tavern. Moe opens an envelope]
Moe: [reading] You have been chosen to join the Justice
                Squadron, 8 a.m. Monday at the Municipal Fortress of
                Vengeance. Oh, I am *so* there!

Department of Dark Energy (3, Funny)

EachLennyAPenny (731871) | more than 5 years ago | (#25914685)

Once they form the Department of Dark Energy they could post job ads reading "Come to the dark side".

Re:Department of Dark Energy (-1, Flamebait)

Anonymous Coward | more than 5 years ago | (#25914725)

One you go black, you never go back. I imagine that's because of the large penis size. I doubt it's the watermelon, chicken, or crack cocaine. Actually, it could be a combo of all of the above that pleases the ladies.

Re:Department of Dark Energy (0)

Anonymous Coward | more than 5 years ago | (#25914787)

I guess that explains men in black, eh?

Is it dark and chocolaty (0)

Anonymous Coward | more than 5 years ago | (#25914717)

I had trouble reading that and I swear it said dank. So if my theory doesn't work out completely, I can fill it with dark chocolate energy until the numbers match my opinion? Neat.

It could be worse... (1, Insightful)

Shturmovik (632314) | more than 5 years ago | (#25914767)

...at least they aren't wasting time and money on String "theory".

Re:It could be worse... (0, Flamebait)

blancolioni (147353) | more than 5 years ago | (#25914801)

Ha ha! It's funny because you have no idea what you're talking about. While you're sitting on your couch throwing spitballs, people with something to say are trying to understand the nature of the universe.

Doesn't the idea of discovering something utterly new have any attraction for you at all? When the first extra-solar planet was reported, what did you do? Whine because there weren't any pictures?

Re:It could be worse... (0)

Anonymous Coward | more than 5 years ago | (#25914893)

Doesn't the idea of discovering something utterly new have any attraction for you at all? When the first extra-solar planet was reported, what did you do? Whine because there weren't any pictures?

I was too busy with attractive girls to care. Have fun discovering "utterly new" stuff if that's what really interests you.

Re:It could be worse... (1)

blancolioni (147353) | more than 5 years ago | (#25915031)

The lack of specificity in your invitation to a dick-swinging contest is ... illuminating.

Re:It could be worse... (0)

Anonymous Coward | more than 5 years ago | (#25918149)

I was too busy viewing attractive girls on the intertubes to care.

Now it seems much more believable.

Ha ha! It's funny because you fail it! (0)

Anonymous Coward | more than 5 years ago | (#25915041)

You got trolled. I especially like that because the troll's comment was actually correct. String conjecture has wasted a lot of time and effort which could otherwise have been applied to something productive, such as real science, rather than to a substanceless fad.

String conjecture = Aether.

What do you have against aether? (4, Insightful)

blancolioni (147353) | more than 5 years ago | (#25915135)

The idea of a luminiferous aether followed naturally from the observation that light acted like a wave, and one of the fundamental things about waves is that they travelled in a medium.

This lead to experiments designed to detect the medium of light (like the famous Michelson-Morley one), to the Lorentz transformations and the Theory of Relativity. The aether conjecture is science at its best: hypothesis, experiment, falsification, paradigm shift. Why it's used as a metaphor for stupidity has always been a mystery to me.

"paradigm shift". You PHB you. (0)

Anonymous Coward | more than 5 years ago | (#25915197)

The point is that String Theory cultists - like the most ardent Aetherists - would rather gouge their own eyeballs out with a rusty spoon than give up on their pet ideas.

Many of the String Theorists I know are very good mathemeticians. Unfortunately they are very poor scientists.

It is not "science at it's best" when fans of postulates endlessly modify and revise the details just to make those postulates fit observation.

In its infancy, String Theory was thin but rather elegant. As it's desperately struggled to survive, it's binged itself into morbid obesity and gone blind from disorders induced by the self-abuse required just to even pretend to be meaningful in any way.

When an idea's adherents have to endlessly contradict themselves while claiming to have done nothing of the sort, just to avoid admitting that their idea has no merit, they cannot describe themselves as scientists.

Religious zealots, perhaps, but definitely not scientists.

So please, stop defending worthless shit. It makes you appear to be a clueless git babbling crap plagiarised from Wikipedia.

Re:"paradigm shift". You PHB you. (1)

OolimPhon (1120895) | more than 5 years ago | (#25915251)

And if you replace "String Theory" with "Dark Energy Theory" in your statements above, it reads exactly the same. Remember "epicycles?"

Re:"paradigm shift". You PHB you. (1)

blancolioni (147353) | more than 5 years ago | (#25915333)

Remember "epicycles?"

This is another of those "dumb science" metaphors that are flung around with no regard for history. The heliocentric model of the solar system did nothing to solve the problem of epicycles, and given what was known at the time, would you have come up with ellipses?

Re:"paradigm shift". You PHB you. (1)

julesh (229690) | more than 5 years ago | (#25917071)

given what was known at the time, would you have come up with ellipses?

Probably not. But the elliptical solution had been known for around 1000 years before it became generally accepted, having been discovered by Aryabhata, c. 500CE.

Re:"paradigm shift". You PHB you. (1)

blancolioni (147353) | more than 5 years ago | (#25917199)

My understanding is that Aryabhata also used epicycles to model planetary movement (and by the way, even if they're not literally there, they can be incredibly accurate, which only adds to my annoyance at the way they get ridiculed). I've heard about the ellipse thing, but never seen any evidence (which, naturally, doesn't mean it's not true!)

Re:"paradigm shift". You PHB you. (1)

blancolioni (147353) | more than 5 years ago | (#25915317)

In fact, paradigm shift was a useful expression long before it was hijacked by business consultants. I suppose this is the destiny of any phrase that describes, shall we say, a great leap forward -- to be misused and misapplied until people end up forgetting what it once actually meant.

How would you prefer the search for a unification theory to proceed? And why are you so angry? It's not for you to decide how people who are smarter than either of us should spend their time.

Re:"paradigm shift". You PHB you. (1)

Nick Ives (317) | more than 5 years ago | (#25918763)

I realise you're trolling, but I suggest you read Structure by Khun.

But of course. (0)

Anonymous Coward | more than 5 years ago | (#25920737)

Somebody dares to question the validity of "string theory" so they are immediately branded a troll.
If "string theory" fanatics weren't so fanatical about defending their theory against any and all enquiry or criticism, maybe scientists wouldn't be so hard on them.
"String theory" has yet to accurately predict anything. Whenever it demonstrably fails - which is often - "string theory" proponents scream 'No it didn't! We were right! Hey, look over there!' before scuttling away in search of another publicist.

Re:What do you have against aether? (0)

Anonymous Coward | more than 5 years ago | (#25917401)

Don't totally count out the ether (not "aether", an archaic spelling which detractors applied -- Michelson and Morley used the modern spelling.) yet.
  After Michelson's original experiments were dismissed for being the result of flawed equipment (when there weren't just blatantly false claims that M-M had detected no drag at all), Dayton Miller confirmed the results several times in the 20s and 30s using better equipment. In 1988, French Nobel Prize winner Maurice Allais repeated the interferometer experiments and also repeatedly detected a very slight drag effect, indicative of ether..

  I think Allais has probably gone off the rails, but hey.

Re:What do you have against aether? (1)

khallow (566160) | more than 5 years ago | (#25918075)

Ether also has a naming conflict with the organic chemical family of the same name.

Re:What do you have against aether? (1)

Migity (1199059) | more than 5 years ago | (#25922439)

Would that be the same "Ether" that the Ether Bunny uses?

72% ? I call bullshit (0)

Anonymous Coward | more than 5 years ago | (#25914815)

bah, everyone knows that dark energy comprises of 62.234% of the total energy in the universe, only a complete fool would believe that 72% is a realistic figure!

GRAMMER NAZIS UNTIE! (0)

Anonymous Coward | more than 5 years ago | (#25914833)

scientists don't know much about it, but speculate that it is present almost since the beginning of our Universe

BAD BAD BAD... REALLY?! I could've sworn that is WAS present.

Re:GRAMMER NAZIS UNTIE! (1)

onedotzero (926558) | more than 5 years ago | (#25915021)

On a related note:

The launch of a spacecraft for the JDEM mission is not planned before 2015.

I have to wonder if this launch has any input from the Department of Redundancy Department.

Re:GRAMMER NAZIS UNTIE! (1)

WillDraven (760005) | more than 5 years ago | (#25915701)

scientists don't know much about it, but speculate that it is present almost since the beginning of our Universe

BAD BAD BAD... REALLY?! I could've sworn that [it] WAS present.

And here I was thinking that it has been present.

The realm of the DoE (0, Troll)

WarJolt (990309) | more than 5 years ago | (#25914845)

Seriously if I was the person managing the DoE budget and I saw something that say "dark energy research" I would think it was a practical joke.

I know it's called dark energy, but since when has astronomic phenomenon been within the realm of the Department of Energy. The DoE is responsible for energy policies. I could understand investment in potential energy producing technologies, but there is not one scientist who could tell me how to harness dark energy. Let NASA figure out what it is and when NASA says we can harness it then get the DoE involved.

Re:The realm of the DoE (3, Informative)

boot_img (610085) | more than 5 years ago | (#25914883)

Actually DOE has always been deeply involved [doe.gov] in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

Re:The realm of the DoE (1)

julesh (229690) | more than 5 years ago | (#25915127)

You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

Except, I don't really see how high energy physics is involved. I mean, it's not as if anybody has proposed a high-energy experiment that could detect it.

Re:The realm of the DoE (2, Insightful)

boot_img (610085) | more than 5 years ago | (#25915185)

Except, I don't really see how high energy physics is involved. I mean, it's not as if anybody has proposed a high-energy experiment that could detect it.

Ultimately, there must be a particle-physics-based explanation for Dark Energy, whether from string theory or something other theory.

And just because Dark Energy not accessible via "classical" accelerator experiments, this does not mean that it should not be considered experimental particle physics research. In other words, instead of using a ground-based accelerator, the Universe is the "poor man's" accelerator [discovermagazine.com] .

Re:The realm of the DoE (3, Informative)

Shag (3737) | more than 5 years ago | (#25915635)

Actually DOE has always been deeply involved in high energy (particle physics) research. They fund a number of accelerators, including Fermilab. Its not clear that any of that research would lead to usable energy sources either.

Good so far.

You can see the Dark Energy research as the intersection of high energy physics (DOE) and cosmology (NASA).

Yes, but don't forget that DOE has its own cosmologists, too. The DOE end of JDEM is being handled by Lawrence Berkeley National Laboratory, which has quite a bit of stuff [lbl.gov] going on in cosmology, mostly under its physics [lbl.gov] division.

(I [lbl.gov] do some work with one of the collaborations [lbl.gov] based there.)

It's a silly thing to measure. (1, Insightful)

Kashgarinn (1036758) | more than 5 years ago | (#25914847)

Once scientists understand that space and matter is the same thing (something you should be able to test and prove here on earth) they should understand that dark matter is just space.

What they're doing by measuring the anomalies with galaxies, and on the smaller scale by making atoms clash together in large colliders, and looking at the results is basically just measuring an effect, and it's really interesting that they aren't doing it with a clear understanding about what they're measuring or why.

What I mean by that is that they aren't doing this testing/measuring to understand the underlying implications, they're doing it to test current mathematical models, and that's why we've failed to understand so-called dark matter and what it really is.

We're probably at the same point in time with dark matter as when scientists before Isaac Newton were pondering the rotation of planets around the sun. there was extensive research into the behavior of the planets, and mathematical models for them going around the sun (as in measuring an effect), but it took someone like Isaac Newton to show people that there is an underlying force that keeps planets around the sun and the same keeps us rooted to the ground.

When someone finally thinks that space and matter must be the same thing, and starts to test that theory and see where and how the 2 match up, we should finally be able to clear up this dark matter nonsense.

Of course Einstein started this with his e=mc^2 - but no one has really looked at this formula when it comes to space and not matter, he looked solely at matter.

Of course being a couch-scientist (worse than amateur scientist), I might be hugely wrong, but somehow, I don't think I am (surprisingly).

Re:It's a silly thing to measure. (4, Informative)

blancolioni (147353) | more than 5 years ago | (#25914897)

Of course being a couch-scientist (worse than amateur scientist), I might be hugely wrong, but somehow, I don't think I am (surprisingly).

Unfortunately, you are wrong, and I guess it's not that surprising, considering your ... interesting take on cosmology. Einstein's work was intimately concerned with the nature of spacetime, so saying that "he looked soley[sic] at matter" is flat-out wrong.

Space and matter are the same? Then either space has a gravitational effect, or they're the "same" in a way that doesn't include a fundamental property of matter, which is to say that they're not the same at all (you'll recognise the quote "in exactly the same way that bricks don't" -- it speaks to nature of classification rather elegantly I think).

So why hasn't the gravitational effect of space been detected? Oh, wait, because the scientists missed something. Silly scientists!

Re:It's a silly thing to measure. (2, Interesting)

Ambitwistor (1041236) | more than 5 years ago | (#25915813)

Space can have a gravitational effect: in general relativity, gravity gravitates. A black hole is a vacuum solution of the Einstein field equations. And if you object to it being vacuum because you can't say what's at the singularity, there are non-singular vacuum solutions too, like gravitational geons [wikipedia.org] . However, they're not stable, so attempts to describe matter as pure space have failed. (Another attempt which also largely failed is to describe particles as wormhole mouths.)

Some people think that dark energy is the gravitational effect of space. See the vacuum energy interpretation of the cosmological constant [wikipedia.org] . That is also different, however, from dark energy being matter, or matter being space.

Matter = space is an intriguing idea, but people have worked on it for over 50 years and haven't made it work. Maybe with a full theory of quantum gravity they could, but I really doubt that would lend any new insight into dark matter or energy, any more than it would suddenly revolutionize our understanding of electrons — the relevant physics would have to be Planck scale and mostly irrelevant except maybe at the Big Bang.

Re:It's a silly thing to measure. (0)

Anonymous Coward | more than 5 years ago | (#25914937)

thank fuck you are here to prove all those scientists wrong! to think they wasted all those years at study when they could just come on slashdot and hear the answered from you?

on a more serious note, your wrong on so many levels it's hard to count them.

Re:It's a silly thing to measure. (2, Insightful)

Ambitwistor (1041236) | more than 5 years ago | (#25915749)

Once scientists understand that space and matter is the same thing (something you should be able to test and prove here on earth) they should understand that dark matter is just space.

Although attempts have been made to unify matter and space (see Wheeler's geon idea), they've all failed. Matter and space appear to be different. But even if they were unified, so what? What's the practical difference between "matter which is secretly some aspect of space" and "matter"? I mean, I can say that an electron is really just "space", but that doesn't prevent it from acting like matter.

it's really interesting that they aren't doing it with a clear understanding about what they're measuring or why.

They have quite concrete ideas of what they're measuring. They just don't happen to agree with your pet ideas of what they're "really" measuring.

what i don't get is... (3, Interesting)

Ignis Flatus (689403) | more than 5 years ago | (#25914857)

if there's so much dark energy in the universe, then why don't we have any local in our own little solar system or planet? how come dark energy only makes the science of things far away off-kilter, yet all our science locally we can measure to 9 or more decimal places? seems like an awfully big fudge factor, if you ask me.

Re:what i don't get is... (2, Insightful)

powerspike (729889) | more than 5 years ago | (#25914887)

maybe it's like fog, when it's far away it looks like a solid cloud.
When it's close, you can see it even thou your standing in the middle of it, it looks completely different, yet the same thing.

Re:what i don't get is... (1)

HonIsCool (720634) | more than 5 years ago | (#25915035)

Most of the universe is space, right? Matter clumps together in formations such as planets and stars, but most of the solar system consists of space. Same for galaxies, and clusters. So, if something were to permeate all that space, well, the density wouldn't need to be very much to still have a large effect. So, if dark energy exists, it will also exist here, but the local effect is too small to measure, and only when looking at a much bigger picture can we see something. Well, that's my lay man understanding...

Re:what i don't get is... (1)

julesh (229690) | more than 5 years ago | (#25915047)

if there's so much dark energy in the universe

AIUI, dark energy is theorized to be everywhere. Including within our own solar system. However, the amount of it in any given space is tiny. Current best estimate is 10^{29} grams per cubic centimeter, which is basically nothing. We can't detect that on any reasonable space. It's only because huge quantities of it are (theorized to be) scattered in the vast distances between galaxies that we are able to detect any effect of it at all.

Re:what i don't get is... (1)

julesh (229690) | more than 5 years ago | (#25915053)

I wrote:

Current best estimate is 10^{29} grams per cubic centimeter

Somehow a minus sign got deleted from that post. I blame slashdot's unicode filtering.

That should, clearly, be 10^{-29} g/cm^2.

Re:what i don't get is... (0)

Anonymous Coward | more than 5 years ago | (#25915139)

Oh yes ! Very clearly !

Minor correction (1)

In hydraulis (1318473) | more than 5 years ago | (#25915797)

g/cm^3

Re:Minor correction (0)

Anonymous Coward | more than 5 years ago | (#25916861)

If you think it is amusing to use a Japanese character that looks like a minus sign, then don't. Please stick to ascii 32-126 until further notice.

Concerning your estimate, isn't the CMB the mass-energy equivalent of about 1e-34 g/cm^3 ? Yet we're able to measure it. It's even "the most precisely measured black body spectrum in nature".

Re:Minor correction (1)

Ambitwistor (1041236) | more than 5 years ago | (#25917005)

Yes. We're able to measure the CMBR, but it's electromagnetic radiation. If dark energy primarily or solely interacts gravitationally, that's a world of difference. The electromagnetic and gravitational interactions have very different strengths. We can't detect the gravitational effects of the CMBR at all, since it's about 100,000 times less energetic than dark energy. Dark energy has only recently been detectable at all through its gravity. That's (one reason) why it's so hard to directly detect dark matter, too.

Re:Minor correction (0)

Anonymous Coward | more than 5 years ago | (#25917341)

Sure. My point was that saying "10^-29 g/cm^3 is small" by itself was an insufficent argument to explain why you can't measure it. One also needs to talk about properties of dark energy (as you did).

Re:what i don't get is... (3, Informative)

boot_img (610085) | more than 5 years ago | (#25915203)

According to the current theory, dark energy does exist in our solar system, its just that you need many, many more than only 9 decimal places to measure it.

Its repulsive effect however increases with scale, so the larger distances you probe, the easier it is detect.

Re:what i don't get is... (1)

Ihmhi (1206036) | more than 5 years ago | (#25915885)

Even though it's 72%, we have those great laws of probability to thank for that.

Let's say I shoot a basketball from the free throw line for 100 shots and I get in 43 of them. From that small set of data, one could say I have a 43% shot accuracy at the free throw line.

Now if I were to make another 100 shots, I wouldn't get exactly 43. I may get more or less, but 43 would be a good representation of an average.

In the case of the dark matter, just because the estimate is that it comprises 72% of the universe doesn't mean that we could take a *very* small portion (i.e., our solar system) and expect it to be comprised of 72% dark matter.

I personally think dark matter probably has anti-gravity and/or anti-light and/or anti-radiation properties. Something that either puts it out of the places we'd be looking (after all, who would look in the large empty spaces between celestial objects?) or something that makes it damn near impossible to detect.

Re:what i don't get is... (2, Informative)

Ambitwistor (1041236) | more than 5 years ago | (#25916069)

Dark matter doesn't have anti-gravity effects. The whole reason why it was postulated in the first place was because of its positive gravity effects: to explain the "missing mass" contributing to galactic rotation curves.

It doesn't exactly have "anti-" light effects. The main working theory is just that it doesn't interact with light (electromagnetic radiation), because it's not electrically charged.

Re:what i don't get is... (0)

Anonymous Coward | more than 5 years ago | (#25918747)

If the earth is 2/3 water I don't understand why there's no body of water near me -- just the bit that comes out of these pipes. I don't understand all this talk of "tides" and "ocean currents." I can understand my world just fine without it.

Dark Matter/Emergy Does Not Exist (5, Interesting)

ObsessiveMathsFreak (773371) | more than 5 years ago | (#25914923)

I was always a skeptic when it came to Dark Matter(I am not an astronomer, so this all technically an uniformed opinion). But now I know that it really is all a load of idle speculation coupled with incomplete investigation, and an excessive dose of hype. It only took a few minutes of googling to come up with this paper [arxiv.org] .

One of the biggest pieces of evidence for Dark Matter is the Galaxy Rotation Problem [wikipedia.org] . Basically the rotations of Galaxies do not behave as astronomers expect them to do, leading to the hypothesis that there is more matter in them that we cannot see, "Dark Matter". The velocity profiles that Astronomers expect to see are Keplerian. That is, they expect star systems in galaxies to behave like planets in solar systems when it comes to orbit speed and distance from the focus of rotation.

The bottom line is, as shown in the paper, this assumption is totally unjustified. The integrals in the 2D galactic disc case do not work out using Shell Theorem [wikipedia.org] , which cannot be applied. They are instead quite nasty singular integrals, but twenty minutes with MATLAB and the "QUAD" function will be all it takes to see that basic gravitational theory most certainly does not predict that Galaxies should have Keplerian(Solar System-like) rotation curves, and there is no reason whatsoever for astronomers to assume this. It's all basic mathematical physics well withing the reach of many reading this post.

The galactic rotation problem is not evidence for Dark Matter. It is only evidence of the need for more applied mathematics courses in astronomy undergraduate degrees. Of course the Galactic rotation problem is not the only evidence for Dark Matter, but it is a big part. The other big piece of evidence was the Galactic Cluster mass problem. It's been a while since I read the relevant papers, but as I recall, Zwicky played hard and fast with the virial theorem, in particular making assumptions about the stability of Galactic clusters.

Again of course, I am not an astronomer. I am essentially a lay person in these matters, so my posts and opinions (not only in this thread) should be taken with a pinch of salt. Still, I stand by my overall skepticism of Dark Matter theories, and I stand quite firmly on my objections to the interpretation of the Galactic rotation problem. I expect that in the near future, as our ability to analyse and simulate galatic dynamics improves, Dark Matter will finally be debunked.

Re:Dark Matter/Emergy Does Not Exist (3, Insightful)

Andr T. (1006215) | more than 5 years ago | (#25914965)

Dark matter is not the same thing as Dark energy. There are separate theories about each one of them.

And even if Dark Matter/Dark Energy really does not exist, I think it's justifiable that people search for it. If the experiments don't match what the scientists say about it, we'll know we need another explanation. The money will not be spent in vain.

Re:Dark Matter/Emergy Does Not Exist (2, Insightful)

julesh (229690) | more than 5 years ago | (#25915033)

Echoing what Andr. T said in his previous post, but in hopefully a little more detail: the evidence for Dark Energy is completely orthogonal to that for Dark Matter. Like you, I'm not an expert on this subject but have done a little reading, and find the D.E. evidence a lot more convincing. Unless there's something fundamentally wrong with general relativity and our understanding of its implications, there is some kind of repulsive force acting on galaxies to push them away from each other.

Now, I'm not totally convinced that this is tied in to the whole cosmological constant business (particularly of the value-varying-over-time variety, which is what this mission appears to be designed to test); that's a hypothesis that has obvious attractions but AFAICS it has received undue attention and there ought to more investigation of alternative hypotheses. But that's an unrelated matter. Something is clearly happening that we don't understand, ergo we need to know more about it.

Re:Dark Matter/Emergy Does Not Exist (3, Insightful)

Xelios (822510) | more than 5 years ago | (#25915119)

My problem with both theories is that they seem to be band-aids applied to current physics to tweak the result to something that matches our observations. For example, we assume that general relativity works the same for superclusters of galaxies as it does here in our solar system. Problem is the results it gives don't match our observations. So is this evidence that the theory breaks down over very large scales? Nope, it just means the universe is mostly made of invisible energy with negative pressure that only interacts through gravitation.

The whole situation reminds me of the aether theories of early physics. The problem then was that Newton's explanation of light provided a very good explanation for reflection, but not refraction or diffraction. The assumption was that since the theory worked well on one set of problems, it must work equally well on another similar set. It didn't, but no matter. By assuming light travels through a medium, the aether, you could tweak the equations to give results close to the observations.

Over the next 200 years this aether gained more and more 'magical' properties to tweak the results of other theories. It had to be a fluid, but also millions of times more rigid than steel. It had to be massless, completely transparent, incompressible and a whole host of other things all at the same time. Everyone was aware of the obvious problems here, but because so many physical theories (theories that gave pretty accurate predictions) were based on it it was just assumed to exist.

In the end aether theory was made obsolete when Einstein re-wrote the incomplete physics that relied on it to deliver accurate predictions. Physics was stuck in a rut for 200 years because it assumed aether must exist, and everyone's efforts were aimed at incorporating aether into physical theories. I just hope this isn't happening again with Dark Matter/Energy.

Disclaimer: I am not a physicist or cosmologist, I just have a passing interest in this stuff, so take what I've said as nothing more than an opinion.

Re:Dark Matter/Emergy Does Not Exist (1)

Xiroth (917768) | more than 5 years ago | (#25915277)

Unfortunately, it does generally take a genius to take the big leaps in our understanding; to forge all our data and half-truths into a coherent whole - that's why it took 200 years (as it turns out, the amount of time between one genius (Newton) and the next) to solve the last one. With the greater number of people studying science and higher accessibility in the world today, hopefully it'll take less time before the next one in the field emerges. Let's hope.

Re:Dark Matter/Emergy Does Not Exist (1)

Andr T. (1006215) | more than 5 years ago | (#25915495)

OK, I understand what you said here, but saying that Physics was 'stuck' for 200 years is a little too much, don't you think? And between Newton and Einstein there were, many, many genius. Faraday, the Curies, Bohr in the same time as Einstein, Planck too. Physics was not stuck.

Re:Dark Matter/Emergy Does Not Exist (1)

Xiroth (917768) | more than 5 years ago | (#25918709)

Sorry, I was referring to that specific field - our understanding of light. Not to denigrate all the good work in other fields.

Re:Dark Matter/Emergy Does Not Exist (1, Interesting)

Anonymous Coward | more than 5 years ago | (#25915875)

What is the purpose of a theory?
If it is to explain observations already made and to make testable predictions about phenomena that have yet to be observed, then the aether theory (which you admit made pretty accurate predictions) served its purpose. Newton's "Laws" still reign in many domains, as their predictions are accurate to useful limits of observation. General Relativity and Quantum Mechanics are clearly incomplete, yet within certain domains, they produce predictions that match observation to the limits of measurement.

The statement that physics was in a rut for 200 years due to the aether theory ignores the work of Maxwell, Faraday, Watt, and countless others who made advances in electromagnetism, electricity, thermodynamics, etc.
The aether theory was in trouble long before Einstein -- Maxwell had negated its primary reason for existence when he demonstrated that an electromagnetic wave could be self-propagating, requiring no "medium" for propagation. That, after all, was the purpose of aether -- to provide a "medium" for the propagation of light.

Far from being an embarrassment, the aether theory is a pretty decent example of the scientific method in action. We start with the idea that light is componsed of particles. We note that light behaves as if it were a wave. We postulate a medium of propagation for the wave and logically derive its properties (massless, fluid, rigid, invisible, etc.).

Maxwell describes EM waves and determines that they CAN be self-propagating (so we don't NEED a luminiferous aether). Michelson and Morley conduct their experiment to demonstrate that the luminiferous aether does not behave as expected, if it indeed exists at all.

Several decades pass before the idea of a luminiferous aether is abandoned, and it is noteworthy that most theories of the time were consistent with the presence or absence of the aether. The reason it took decades to fully abandon the idea is that it DID explain some things. Of course, eventually, these same things were explained in other ways, and the aether was abandoned as a needless complication (Occam's Razor).

Some of the ideas associated with the aether persist. One cannot hear of General Relativity's "frame dragging" (a rotating, massive body dragging space-time around itself) without thinking of the idea that Earth would drag the aether around itself (an early attempt to explain the results of the Michelson-Morley experiment).

So, the aether theory was developed because it explained what was observed. At some point, there were gaps in what it could explain, and alternate explanations surfaced. After some time, the alternate explanations provided better explanations in all domains, and the aether theory was abandoned. Had the aether theory been simpler than Maxwell's equations or had it produced some results that could not be as easily obtained by other means, we might still be saying "it is helpful in analyzing this situation to postulate an invisible, massless, incompressible, rigid fluid through which light propagates..."

Re:Dark Matter/Emergy Does Not Exist (2, Insightful)

Ambitwistor (1041236) | more than 5 years ago | (#25916001)

My problem with both theories is that they seem to be band-aids applied to current physics to tweak the result to something that matches our observations.

That's how science works. If you see something anomalous, you start by applying the most minimal possible tweak to explain the anomaly. If that doesn't work, you expand your hypotheses to be more radical until you hit upon something that works.

As it happens, the most vanilla, boring possible modification — a cosmological constant — seeems to explain our observations, agreeing with both supernova luminosity-redshift relations and the cosmic background radiation angular power spectrum. That disappoints a lot of theorists who want to come up with new dark energy theories. In fact, it's not even really a modification of existing theory. A cosmological constant has been present in Einstein's theory from the very beginning, in 1915. Einstein later took it out of his theory because he didn't see a need for it. Now we do, because we can make more sensitive measurements.

Re:Dark Matter/Emergy Does Not Exist (1, Informative)

Anonymous Coward | more than 5 years ago | (#25916109)

I think you're confused. It wasn't Einstein that debunked the ether theory, it was Michealson and Morley in 1887:

http://en.wikipedia.org/wiki/Michaelson-Morley_experiment [wikipedia.org]

More research, less blather, please.

Re:Dark Matter/Emergy Does Not Exist (1)

Krabbs (1319121) | more than 5 years ago | (#25916141)

If it was a problem with the large size of galaxies, the error would be proportional to the size of the galaxy. Calculations show that ordinary matter consistently makes up around 1/5 of the matter needed to account for the gravitation. That is an error factor of 400%. To somehow assume that just because mass is gathered in something we call galaxies it suddenly follows completely different equations that consistently gives the same error, is much more unreasonable than the existence of dark matter imo. Also, there are other independent proofs that result in almost exactly same amount of dark matter.

Re:Dark Matter/Emergy Does Not Exist (4, Insightful)

Ginger Unicorn (952287) | more than 5 years ago | (#25915201)

Does this temper your skepticism any? [stanford.edu]

I find it hard to accept the idea that some lone guy on slashdot has found a problem in the maths used by all the astronomers in the world who describe galaxy rotation, or indeed that even if you had, it seems galaxy rotation is not the sole piece of evidence for dark matter [wikipedia.org] .

Re:Dark Matter/Emergy Does Not Exist (2, Informative)

boot_img (610085) | more than 5 years ago | (#25915305)

It only took a few minutes of googling to come up with this paper [arxiv.org] .

Note that "this paper" has not yet been refereed and accepted by a journal. It is conventional, when submitting papers to arxiv, to indicate to what journal the paper has been submitted, whether it has been refereed and accepted or not. There is none of that information here. Normally a paper submitted in March 2008 would have been accepted and published by end of Nov 2008 if it had been. I suspect that it has been rejected.

Re:Dark Matter/Emergy Does Not Exist (1)

steelcobra (1042808) | more than 5 years ago | (#25919075)

The key problem with this view is that even if the paper is accurate, based on observation and experimentation, and is reproducable, if it's outside the current dogmatic system it will be rejected.

Look up Halton Arp, Peter Duesberg, and Immanuel Velikovsky. The latter, for using all available evidence to construct a wildly different view of the solar system that matches history, was ignored, criticized without the critic having read his work as unscientific or being biblically based, when in fact all his references to such texts are verified by other sources.

So be careful about the idea that just because it's generally accepted it's right.

Re:Dark Matter/Emergy Does Not Exist (1)

boot_img (610085) | more than 5 years ago | (#25920393)

I am an astronomer. I don't know about Duesberg or Velikovsky, but I can tell you that Halton Arp's theories do not agree with the available evidence.

Contrary to the romantic notions of some, there is no "conspiracy" against him. There is a sound, rational reason that he is ignored: its simply that his ideas do not match the observations.

Re:Dark Matter/Emergy Does Not Exist (1)

Ummite (195748) | more than 5 years ago | (#25915783)

We have a scientist, named "Jean-Pierre Petit" (see wikipedia). He predicts some of galaxy configuration. Please read his paper, it's interesting.

Re:Dark Matter/Emergy Does Not Exist (1)

VShael (62735) | more than 5 years ago | (#25915943)

I think you're quite right, and hence the use of the "epicycle" tag on this story.

Epicycles, if you don't know, were the artificial additions to the "circular" orbital theory, which became more and more clumsy and unwieldly, until some bright spark called Copernicus simplified the whole thing. And then when we finally worked out orbits were elliptical, not circular, we looked back on epicycles and said "Of course! How could we have been so stupid!"

Epicycles. Dark Matter.

Re:Dark Matter/Emergy Does Not Exist (1)

Ambitwistor (1041236) | more than 5 years ago | (#25916055)

There's nothing wrong with epicycles as a theory. It's just Fourier analysis. The real problem with epicycles is not that they're wrong, but they're not predictive. (There's no theory to say what the Fourier coefficients ought to be.)

Dark matter is not like epicycles. You can put in assumptions about dark matter inferred from one set of observations (e.g., galaxy scale physics), and make predictions about different observations (e.g., the cosmic background radiation), and you find that the predictions work.

Re:Dark Matter/Emergy Does Not Exist (2, Insightful)

Ambitwistor (1041236) | more than 5 years ago | (#25915947)

I was always a skeptic when it came to Dark Matter(I am not an astronomer, so this all technically an uniformed opinion). But now I know that it really is all a load of idle speculation coupled with incomplete investigation, and an excessive dose of hype. It only took a few minutes of googling to come up with this paper.

Oh yeah. A few minutes of Googling turns up an unpublished manuscript which overturns 80 years of research and thousands of papers. A manscript written by a guy who runs a mail-order crystal business and a former Xerox employee who studies fluid droplets. (I bet I'm going to hear "but Einstein was a patent clerk" real soon now ...) Which cites Electric Universe theory papers. That's totally credible.

It is only evidence of the need for more applied mathematics courses in astronomy undergraduate degrees.

Yeah, everyone who has worked on dark matter flunked basic undergraduate astronomy. That's probably it. I bet they can't implement Newton's law of gravity in an N-body simulation either.

I don't really feel like working through their manuscript, but it seems rather reminiscent of the Cooperstock and Tieu [arxiv.org] paper which tried to do away with dark matter by introducing a thin disk of regular matter (e.g., here [arxiv.org] ). It was also reported on Slashdot, and debunked within a month. (I suspect the only reason anyone bothered to write up a rebuttal is that Cooperstock has a reputation in gravity and people were worried someone might buy it. Most of these flawed papers just get ignored.)

Re:Dark Matter/Emergy Does Not Exist (1)

Krabbs (1319121) | more than 5 years ago | (#25916011)

The shape of the cosmic microwave background radiation and the ratio between the different elements in the universe(like H, He) are also proofs of dark matter. The fact that the amount of dark matter needed to make the behaviour of galaxies make sense is in almost perfect agreement with the above observations is indeed very strong evidence for the existence of dark matter. That they should somehow by mistake all add up to the same amount of dark matter(about 22%) is insanely unlikely. Anyway, the article was on dark energy, which is a different matter. :p

Re:Dark Matter/Emergy Does Not Exist (1)

fmoliveira (979051) | more than 5 years ago | (#25917619)

There were already better evidence with gravity lensing or something like that. The evidence for dark matter keeps growing larger and larger.

Re:Dark Matter/Emergy Does Not Exist (1)

steelcobra (1042808) | more than 5 years ago | (#25918891)

You should check out James P. Hogan's Kicking The Sacred Cow. It presents a variety of alternate, observationally/experimentally proven alternatives to the mainstream view that have been ignored or flat out rejected by the dogmatic mainstream science. Such as that an electromagnetically formed plasma universe concept actually explains everything. Or that "Dark Matter" is really just molecular hydrogen (H2), which isn't detected easily, but is far more prevalent than atomic hydrogen. As well as a variety of other subjects.

Re:Dark Matter/Emergy Does Not Exist (1)

syousef (465911) | more than 5 years ago | (#25919153)

I have a masters in Astronomy but have never worked in the field and it's the kind of degree more suited to teaching than research. Nevertheless...

I skimmed the paper and I don't think it's saying what you think it's saying.

From section 4 (2)
"By contrast, others inaccurately assume the galactic mass distributions follow
the measured light distributions (approximately exponential), and then the measured rotational
velocity curves are not duplicated. But this assumption of a simple direct relationship between
light intensity and mass is very inaccurate. This so-called Mass/Light ratio is inaccurate since both
the temperature and opacity/emissivity are important but ignored variables."

In other words the authors believe that the missing mass is indeed there, but that it is ordinary matter, but that it is literally dark (that is it doesn't shine as brightly).

I don't think the math is cutting edge, even if they have taken a novel approach - it looks to me like n-body problem work with standard Newtonian mechanics. (I could be wrong, and am happy to be corrected. It's been years since I looked at this stuff and I never did the calculus formally. I certainly don't have time to go compare this work to other classic work). To their credit they explicitly state that no modification of Newtonian mechanics is required for their work.

A Marine's tale. (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25914935)

There are two things Marines are always taught
1)To keep your priorities in order
2)Know when to act without hesitation

An atheist professor was teaching a college class and he told the class that he was going to prove that there is no God.

He said, "God, if you are real, then I want you to knock me off this platform. I'll give you 15 minutes!"

Ten minutes went by.

The professor kept taunting God, saying, "Here I am, God. I'm still waiting."

He got down to the last couple of minutes and a Marine just released from active duty, and newly registered in the class, walked up to the professor, hit him full force in the face, and sent him flying from his platform.

The professor struggled up, obviously shaken and yelled, "What's the matter with you? Why did you do that?"

The Marine replied, "God was busy, so He sent me."

Unfortunately for the Marine, God didn't give a shit if the professor pressed charges or not, so when the police came to arrest him no force in heaven or Earth interceded. He was processed and put in a cell. While in the cell, he met an atheist hobo who claimed there was no God, so he beat that guy up too. over 9000 other inmates attempted to haul him off the hobo, so he beat them up as well. One of them suffered severe blunt force trauma and died in the ambulance on the way to the hospital. His bailed was not made and he waited in prison until the day of his trial.

Because of this, the marine was found guilty of four counts of aggravated assault and one count of 2nd degree murder and was sentenced to 15 years time served in state penitentiary, with parole opportunities after 7. Unfortunately, the judge was a well known, avowed atheist so the marine felt compelled to give him a piece of God's mind. The marine leaped onto the defense table and, using his scheming Jew lawyer as a lawn dart, struck the judge in the face. Parole opportunities were revoked.

While in jail the marine found himself very busy fighting anyone who showed the slightest lack of faith in God. Unfortunately, one afternoon in the sixth year of his incarceration, God instructed him to pick a fight with a particularly large man of Hispanic descent and, although he prevailed in the initial conflict, the 27 Latin Kings members who fell upon him following his victory quickly delivered blows sufficient to render him incapacitated.

Because of the severity of his injuries, he was given a bed at the prison hospital. While there, the prison psychiatrist conducted extensive interviews, ultimately determining that the marine was suffering from post traumatic stress disorder and late onset schizophrenia. He was immediately put on a extensive array of powerful anti psychotics and anti depressants; all of which he secretly was not taking, because God had told him the medication was from the devil and was being used by heretic Muslims and atheists to sever his ties to the Lord, his God. His condition continued to worsen and he spent more and more time locked in solitary confinement for his disruptive behavior. While there he would cry and scream and pray to the lord for guidance. In turn the lord would fill his eyes with visions of ultimate triumph over evil; the streets of pagan cities, clotted with the thick heart blood of the nonbelievers; abortion clinics fat with flies and the rotting flesh of the defilers; the righteous dancing in the vaulted crypt of the world as the sky turned to red ash and caught fire. He wept with joy as the profound visions filled his soul; the nourishing screams of the nonbelievers as they were dragged down into perdition, filled his ears and echoed in his head like beautiful music.

Unable to attend church in solitary, the marine began to despair. God then gave him the power to transubstantiate anything, so he began tearing great chunks of his own flesh from his body, at which point he would transform them into the body of christ and raise them to his mouth with trembling hands and consume them greedily. Likewise he transformed his blood to that of his savior, so that he could receive sacrament. He truly understood how well loved he was by his creator as he lay in his cell, weak from blood loss, cupped in the hands of a loving God.

Some time later he awoke again in hospital. This time he found he was strapped to the bed with thick leather restraints. He could no longer refuse to take his medication; they were delivering it into his bloodstream with needles. He cursed at them and tried with all his might to break free, imagining himself not unlike Samson. He knew they were all secret atheists and were working against him, working against GOD. But the loss of blood and effects of the medication made him too weak to fight back. So instead he lay there glowering.

Days turned to weeks. As time wore on the voice of god diminished, though never truly left him. Occasionally he could hear far off whispering coming from radio static or the rhythmic humming of the prison buses. It wasn't the same, though. God was no longer in him; he was more like a scent one occasionally catches hanging in the air, or riding on a breeze through the room, before disappearing entirely. His mind was dulled and slow and nothing made sense. Movement was laborious, like the air around him had turned to pudding. He slept more, no longer worked out. Fat replaced his muscle and stubble was upon his chin at all times. Before he was medicated, he had a sense of purpose and clarity that was almost terrifying in its starkness. But now... nothing made any sense. Without god he felt small and confused and alone.

It wasn't so bad, however. In the state mental institution he was moved to shortly after his second release from the hospital he had cigarettes and magazines. The paper was available on Sundays and he had been eligible to take part in the patient work program. He enjoyed working in the garden. Planting made him feel close to the earth and like he was accomplishing something. Most weekdays he sat and watched television in the commons with the other patients. Sometimes god snuck into the tv. Most times not.

Five years into his stay at the institution, God intervened again, in the form of Ronald Reagan. His groundbreaking movement to privatize the mental health industry made it no longer feasible to house patients of staff many asylums and so the marine, having completed his sentence, was released into the world. Without access to medication and therapy he quickly relapsed into psychosis.

Wandering the streets, his head full of divinity, the marine slept in alleyways and preached on street corners, spending what money was given to him on malt liqour. He collected cans and as he did so he sang hymns of his own design and screamed and spat and those the Lord pointed out to him as unbelievers. He came to live beneath an overpass for a time, until the cops chased him and the other squatters away. Eventually, he caught a ride on a departing freight train, getting off at a stop near Austin, Texas.

In Austin he witnessed a great congregation of evil, the likes of which he had never seen in all his travels throughout the Midwest. Queers, idolaters, the vain and the godless; fools and sinners all, ran the town. It was obvious that God had sent him there for a reason. There was much work to be done and he could hardly wait to begin.

That first night there he began preaching on the steps of the public library. God filled his voice with fire and he in turn filled the ears of the passerby's. Most laughed and jeered and moved on; some looked simply uncomfortable at his presence. They were how he knew he had power; his righteously acted as a divine rebuke against them, and they could not bear to look upon a man of god.

One day, months after his successful entrance as a fixture of Austin life, while he was preaching the word to any who would hear he was approached by a couple. They looked young and stylish, in a intentionally shabby way- common elements of what another hobo revealed to him was a subculture calling itself "hipsters". This hobo had gone on to explain that, while he didn't understand what it was they did or believed in, they sometimes gave a lot of change.

"What are you supposed to be," the man said. "Some kind of preacher?"

The marine wasted no time, "I am that which lies beyond in all of us. I speak the truth and so am transformed by the truth I know what I am, I know what you are. I know beyond knowledge and you had better find the lord before he finds you, child!" he said, flecks of spit gathering in his beard. His chest heaved as he labored to catch his breath; it pulled his t shirt up halfway past his belly. He pulled it down with the hand not holding his bible.

The girl laughed at this and lopped her arm through the man's, pulling him closer. "He's really weird."

"Yeah, a regular coco-nut. Man, you're a little crazy, aren't you?"

"I am the only one here sane enough to see, to see, to SEE the dawning of the Lord's wrath! He is with us now; he is judging us, preparing to reveal himself and exercise his GREAT WRATH!"

"Check it out, Marie. He's panting, haha."

"C'mon, let's go. He's a little intense. I think he might be on drugs, or something." The girl tugged at his arm.

"No, wait. Poor guy. He needs help, you know?"

"C'mon Charlie; let's go."

"I said wait, Marie. Jesus. Hold up while I help this guy. Hey, hobo Joe. Hey, look at me!"

The marine met the man's gaze with a fixed stare. God painted thick black lines of corruption over the man's body. He could see how dark and venal this creature truly was.

"Listen, I'm to help you, hobo Joe. See, you're a little wacky in the wicky woo, you know? All this god stuff ain't helping you either. If you wanna get your life straight you have to go get help. And you have to realize there is no such thing as God."

Lightning shot up the marine's spine. This one was placed before him by the divine hand of providence. He remained silent, as he had done before, and waited for the right moment.

"You know what I mean? It's a fairy tale that some people made up to feel better about things and your crazy brain just took it too serious. But there isn't any God."

"There is a God," the marine said quietly.

"No man, there isn't! Listen, God punishes the wicked, right? Well man, biblically speaking, I'm the wickedest man around. Now I'm not a thief or a murderer or none of that, but I sure as shit don't believe in God. To make it worse, I say horrible things about your imaginary God all the time. Not just to friends and family; I have a talk radio program that broadcasts to over 10,000 listeners and I say horrible stuff about your God to them all the time." He pushed a floppy lock of black hair from his brow "and I'm still here."

The marine gritted his teeth and balled up his fists, shaking almost imperceptivity with rage, "You are," he said.

"Right, so shouldn't I be dead right now if the God of that bible you're holding is real and doesn't like to be made fun of? Should he get back at me somehow? He's not, man; I sure as hell live a lot better than you. At least I don't smell like piss and Wild Irish Rose."

The marine was silent.

The man looked up at the sky and continued taunting God, "I'm standing right here, God! Do something to show this man you're real, or he's gonna have to admit you ain't there!"

The Marine waited a few minutes, then when he felt God's presence in him say the word, he stepped forward and grabbed the young man by the hair and swung him in a 140 degree arc, so that when he put him down the man was trapped between the Marine's body and the large stone lions outside the library. His woman screamed his name, but the Marine didn't care. The man curse and tried to fight back, but even with youth and health on his side, he was no match for the brute force of the marine's muscle, long hidden under thick layers of fat. He turned the man around, forced one arm behind his back and with his free hand (the bible had clattered to the ground when he advanced on the atheist) grabbed a thick handful of the sinner's greasy hair. He pulled it back with all his strength, bringing the man's head back with it.

"Ahhh, fuck! What the hell are you doing?" the man said.

He said nothing. The woman began to beat on his back, screaming at him, so he let his back leg out real quick, using a kick they had taught him in the core. He didn't see, but he could hear the greenwood snap of her ankle, the squeal of pain and the thud as she hit the ground.

"You're ffffucking crazy, you..."

The Marine cut him short, smashing the man's face as hard as he could against the stone. The first few times, the man struggle back with surprising force, but after the tenth time, he did little more than gurgle, a fair share of his face now smeared across the stone or caved into deeper recesses of the skull. When the Marine was sure he had done all that God wanted him to, he dropped the body and turned to leave.

By now a sizable group had gathered. It was so good to have a congregation, the Marine thought, and he gave the man's corpse a solid kick in the midsection to emphasize the point of his sermon. As the people in the front began to see what he had done the screamed and pushed away against the crowd. The glory of the lord is truly hard to take sometimes, he thought, but we must all bear witness.

The Marine could see the cops pushing through the people now, guns drawn. He knew he wouldn't be taken alive this time. God had made that clear. It was now his job to die a martyr and lead other souls into the glory of the way.

The woman at his feet looked up with tears of rage. "What's the matter with you? Why did you do that?" she said.

The Marine replied, "God was busy, so He sent me."

Re:A Marine's tale. (0)

Anonymous Coward | more than 5 years ago | (#25915023)

The Marine replied, "God was busy, so He sent me."

The man with the small testicles?

How is it meant to work then? (0)

Anonymous Coward | more than 5 years ago | (#25914957)

TFA doesn't say a single word on how this mission is meant to work! Looking at http://universe.nasa.gov/program/probes/jdem.html [nasa.gov] it seems it's to do with analysing the expansion rate of the universe by looking at very stable light sources. Anyone know how this helps them find the stuff?

Re:How is it meant to work then? (1)

Ambitwistor (1041236) | more than 5 years ago | (#25916179)

If you want to reconstruct the expansion history of the universe, you need to know where various objects were located in the past.

By looking at the redshifted light from a distant star, you can tell by what factor the universe has expanded. (It's equal to the factor by which the wavelength of light is stretched.) By the Hubble distance-redshift relation, you can tell how far away the star is: in an expanding universe, faster moving and more redshifted stars are farther away. That relation only works if the universe's expansion isn't accelerating, though.

You can also tell how far away a star is if you know how bright it is. If it looks really dim compared to its true brightness, then it's far away. This method of measuring distance only works if you know how bright the star really is. There is a special kind of supernova (Type 1A) which always has the same brightness. (Or rather, there is a known relationship between its brightness and the rate at which it fades out after the nova.) If you look at those stars, you can measure their distance just from their apparent luminosity.

The problem is, the two methods don't agree with each other: some supernovae are much dimmer than the redshift Hubble relation implies. That implies that something made them accelerate away, since the Hubble relation assumes no acceleration. By comparing the two measures of distance (redshift-inferred and brightness-inferred), you can work the amount of excess acceleration. This is dark energy.

The JDEM mission is supposed to measure supernova redshift and brightness, and thus measure the strength of dark energy.

See here [lbl.gov] for more information. This article is on SNAP, the predecessor to JDEM.

Another source of dark energy (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25915091)

I hear Africa is a good source of dark energy. Not only is it renewable, but it doesn't emit anywhere near as much greenhouse gases as traditional sources.

I was wondering (1)

BlindRobin (768267) | more than 5 years ago | (#25915133)

Is it true that, presuming one can't grasp it, dark energy doesn't not matter ?

Damnit! (1)

DoofusOfDeath (636671) | more than 5 years ago | (#25915233)

Bush even got it into an arms research race with the Protoss!

We'd best just leave it alone . . . (2, Funny)

PolygamousRanchKid (1290638) | more than 5 years ago | (#25915347)

If NASA and the DoE start yanking on the Dark Energy in the Universe, they might find that attached to the other end are . . . Dark Energy Creatures.

They might not be amused with the antics of NASA and the DoE.

"Hey, you, Earthling! Is this your Joint Dark Mission Probe, that just broke my window?"

You have been warned.

solution to dark energy / dark matter crisis (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25915431)

i found it... its niggers

ever see those sheboons with hideously enormous asses? thats where all the unaccounted for matter in the universe is located

Too much turkey? (1)

kaplong! (688851) | more than 5 years ago | (#25915473)

I'm surprised by the low quality of comments so far. Must be the fallout from Turkey Day here in the US... Anyways, Dark Matter and Dark Energy are two very different concepts. Dark Matter is what makes the universe clump together. Galaxies are just the markers or highlights in the densest spots of the Dark Matter distribution, pretty much like foam on the tips of waves. There's plenty of observational evidence besides rotation curves. Simulations of the evolution of the universe these days are pretty much Dark Matter simulations, and they work out surprisingly well coming up with the string/plane and void structure that we observe today. I don't think there's too much left to discuss there concerning the existence of this stuff, even though we do not know at all what it is made of in terms of particle physics constituents (there are plenty of hypotheses of course). Sorry if you missed it... (Seriously, there's a huge job left trying to explain science to the general public. Especially if we want to keep getting funded...)
Dark Energy is a more speculative concept, but the basic fact that galaxies at far enough red shifts seem rarer than even flat cosmic evolution models tell is hard to discuss away. Basically, the universe expands faster than even a completely empty universe would, so you need something else than matter (baryonic = visible, or dark). Adding matter would just make it clump more and slow down the expansion.
Now, the cool thing about all these Dark Energy projects and missions (with JDEM just being the biggest of them) is that no matter what you find in the end, you will learn a great deal about the time evolution of the universe, by looking far back into vast areas of space. Counting supernovae, deducting the lumpy structure of matter (dark & visible) by observing distortions in the distribution and apparent shape of galaxies, all this gives you sort of a time-lapse movie of the large scale evolution of the matter distribution. Just google dark energy, or have a look at the DES white paper (https://www.darkenergysurvey.org/the-project/survey_documents/DES-DETF/DES-DETF_whitepaper_v1.7.7-final.pdf)if you want to learn more about this stuff.

Ep!;? (-1, Troll)

Anonymous Coward | more than 5 years ago | (#25915741)

So that is what a ZPM gets it's power from now we (1)

Joe The Dragon (967727) | more than 5 years ago | (#25915867)

So that is what a ZPM gets it's power from now we need a way to make them and we better do that off world.

Re:So that is what a ZPM gets it's power from now (0)

Anonymous Coward | more than 5 years ago | (#25917417)

What I want to know is, if we build a ZPM, will that bring the cost of production down to a point where we can STOP CANCELING OUR GODDAMN SCI-FI SHOWS?!

Bright abd Dark Sides of The Force (0)

Anonymous Coward | more than 5 years ago | (#25916453)

This is likely off-topic or flamebait, but wtf? The meme (what's-the-opposite-of-illuminati?) attached to the headline clearly requests an answer.

My dictionary defines "illuminati," e.g. as "persons claiming to possess special enlightenment," so I propose "obscurati," which should be understood to mean "persons claiming to possess special ignorance [or confusion]."

However, in the scientific context of the NASA/DoE endeavour, it is probably more appropriate to translate "obscurati" as "persons claiming to _seek_ special ignorance [or confusion]"

Re:Bright abd Dark Sides of The Force (1)

Kayden (1406747) | more than 5 years ago | (#25918883)

No, obscurati is already taken. It's defined as "persons claiming to understand Dennis Miller's jokes."

Wrong physics? (1)

carvalhao (774969) | more than 5 years ago | (#25916461)

This will kill my karma, but I just have to ask: isn't all this "something we can't see that's messing up our physics" putting us off the possibility that our physics models may just be flat out wrong?

I mean, would we have a relativity theory if Einstein had stuck to Newtonian physics and stated that the errors measured were caused bay some misterious force/matter/energy that we couldn't see?

Re:Wrong physics? (1)

Ambitwistor (1041236) | more than 5 years ago | (#25916511)

This will kill my karma, but I just have to ask: isn't all this "something we can't see that's messing up our physics" putting us off the possibility that our physics models may just be flat out wrong?

Yes, and that's why various dark energy theories introduce new physics (such as new types of particles or modifications to gravity).

I mean, would we have a relativity theory if Einstein had stuck to Newtonian physics and stated that the errors measured were caused bay some misterious force/matter/energy that we couldn't see?

Would we have discovered Neptune if we had tried to invent new physics instead of postulating that some unseen body was perturbing the orbit of Uranus?

Anyway, Einstein's solution was to modify Newton's theory of gravity. The leading solution is to modify Einstein's theory of gravity by adding a cosmological constant. (Actually, it's really just restoring Einstein's theory to its first published form, which originally had dark energy in it.)

What the mission is and why DoE is involved (1)

Tom Womack (8005) | more than 5 years ago | (#25916605)

For those wondering why the Department of Energy is building a space telescope rather than focussing on nuclear things, the Department of Energy funds the SLAC Linear Accelerator centre at Stanford and it's people at that centre who have designed SNAP, a spacecraft that happens to fulfill exactly the requirements NASA put forth for JDEM.

The Dark Energy Mission is a wide-field high-resolution space telescope; a hundred million or so pixels of 0.2 arcsecond extent, and a five-foot main mirror. The idea's to survey most of the sky at about four times the resolution possible from Earth (adaptive optics, which are useful for very high-resolution imaging of very narrow fields from Earth, are not useful for these large fields).

There are two mission models: take pictures of galaxy clusters and work out the mass in them implied by the way the gravity of the foreground cluster distorts the light from background galaxies, and take pictures of lots of galaxies looking for supernovae.

It's perhaps not entirely accidental that this large-scale high-resolution survey work will produce very attractive images of the sky for outreach, a task at which the JWST replacement for Hubble, being aimed more at work in the infra-red and on the faintest and most distant objects, is not as superb as Hubble.

Re:What the mission is and why DoE is involved (1)

Shag (3737) | more than 5 years ago | (#25917685)

For those wondering why the Department of Energy is building a space telescope rather than focussing on nuclear things, the Department of Energy funds the SLAC Linear Accelerator centre at Stanford and it's people at that centre who have designed SNAP

Uh... not to fan the flames of any Bay-Area turf wars, but that team [lbl.gov] is led by people from Lawrence Berkeley National Laboratory and University of Califoria at Berkeley. Yes, there are a couple Stanford people who work on things like electronics and pointing, but they're a small fraction of the whole project.

You were close, though: the Department of Energy funds Lawrence Berkeley National Laboratory. :)

Let me go on record (1)

mudshark (19714) | more than 5 years ago | (#25917395)

I'll wager that this dark energy stuff is actually laziness, and there's heaps more of it than anyone ever imagined.
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