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Galaxy Clusters' Stunted Growth Confirms Dark Energy

kdawson posted more than 5 years ago | from the glimmer-of-fur dept.

Space 167

A new study of 86 galaxy clusters in the early universe has provided independent confirmation of the existence of dark energy. In its absence, gravity's pull should have caused the number of clusters to increase by a factor of 50 over the last 5.5 billion years. What is observed is a factor of 10 increase. "Together with earlier observations... the new data strengthen the suspicion — but do not prove — that dark energy is a weird antigravity called the cosmological constant that was hypothesized and then abandoned by Albert Einstein as a 'blunder' almost a century ago. If that is true, the universe is fated to empty itself out eventually, and all but the Milky Way's closest neighbors will eventually be out of sight. ... Adam Riess of Johns Hopkins and the Space Telescope Science Institute, said: 'If this was a fox hunt and dark energy was the fox, I think they have closed off another escape route. But there is still a lot of terrain left for the fox, and we've seen little more than a glimmer of fur.'"

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167 comments

Logic (2)

Shadow7789 (1000101) | more than 5 years ago | (#26142373)

I love how one part of logic can necessitate the existence of this dark energy, but the other questions how most of our universe can be made up by something we cannot see. Oh science, why are you such a cruel mistress.

Re:Logic (2, Informative)

Anonymous Coward | more than 5 years ago | (#26142425)

Yeah, I often wonder about how I manage to breathe. There's all this stuff I can't see, and I'm not really sure it's really there.

(Hint: Just because something doesn't interact with photons doesn't make it pseudo-scientific.)

Re:Logic (4, Funny)

Thanshin (1188877) | more than 5 years ago | (#26142663)

You think that's air you're breathing now?

Re:Logic (0, Redundant)

sumdumass (711423) | more than 5 years ago | (#26142833)

We can physically and empiricaly test and manupulate air. Can we do that with this galaxy or Dark matter?

Proof or confirmation is an over exaggeration. I can point to any anomaly and claim that because it defies known science, it confirms God exists. In fact, I could claim anything that doesn't Look as I think it should and claim it supports anything that isn't proved. Unfortunately, I could be just as wrong.

Re:Logic (2, Funny)

dreamchaser (49529) | more than 5 years ago | (#26143291)

That whooshing sound was GP's Matrix themed joke flying right over your head. Turn in your geek card at the desk on your way out please.

Re:Logic (1, Funny)

MaskedSlacker (911878) | more than 5 years ago | (#26143637)

I think missing a reference to a the Matrix should only burnish ones geek credentials--it's like the star wars prequels. I've tried so hard to forget.

Re:Logic (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26143923)

Except that this reference was to the good one.

Animated series? (0, Offtopic)

berend botje (1401731) | more than 5 years ago | (#26144721)

The good one? You mean the animated series? 'cause everything later, and certainly those three live action movies, sucked rocks.

Re:Animated series? (0)

Anonymous Coward | more than 5 years ago | (#26147367)

I'm sorry, all films had plus points. Namely Carrie Anne Moss AND Monica Bellucci. (If you don't think they're hot, then you've probably never had sex).

Re:Logic (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26144519)

Here! Here!

Re:Logic (0)

Anonymous Coward | more than 5 years ago | (#26145347)

First Matrix was like the original Star Wars trilogy: still great in spite of the later endeavors with the franchise sucking ass.

Re:Logic (0, Offtopic)

StarfishOne (756076) | more than 5 years ago | (#26143655)

No, I nearly died choking on my lunch when I read your reply. ;O

Re:Logic (1)

jabithew (1340853) | more than 5 years ago | (#26144047)

(Hint: Just because something doesn't interact with photons doesn't make it pseudo-scientific.)

*cough*

Air does interact with photons. Just not ones we've evolved to see. Because, you know, what would be the point otherwise?

Re:Logic (2, Insightful)

CarpetShark (865376) | more than 5 years ago | (#26142603)

Yes, what an impossible thing. To think, that humans, the pathetic little barely-smarter-than-a-chimp creatures on a rock in the middle of nowhere might have... *gasp* limits ;)

Re:Logic (1, Offtopic)

Snaller (147050) | more than 5 years ago | (#26143463)

That comment is ample proof that the wrong people are allowed to moderate here.

Re:Logic (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26143469)

Ore wo dare da to omotte yagaru!

Re:Logic (3, Informative)

floodo1 (246910) | more than 5 years ago | (#26142869)

The part of logic that "necessitates" the existence of dark energy is inductive logic, which relies on inferences. Right now the evidence infers that dark matter exists, but as is the case with all inferences it could be wrong. Hence TFA stating that this discovery adds to the evidence but does not PROVE its existence (which would be deductive logic).

In either case dark matter may not be necessary at all. This is because in logic necessary has a hugely different meaning than the way you used it :( To quote from wikipedia
* possible if and only if it is not necessarily false (regardless of whether it actually is true or false);
* necessary if and only if it is not possibly false;
* contingent if and only if it is actually true (and so possibly true) and not necessarily true.


So even if we can prove the existence of dark matter, we've only shown it to be contigent. We'd still have some heavy lifting to do to show that it cannot possibly NOT exist.

Re:Logic (0)

Anonymous Coward | more than 5 years ago | (#26143679)

But then again, nothing is ever proven in Science, it is just given a mountain of evidence.

And no, I'm not religious - I'm quite athiest at this point, but I try to be as honest as possible.

Science is the best guess that we have at explaining natural phenomena, nothing more. However, it strives to be better than religion because it attempts to prove bad theories wrong at every turn. It is simply an endless search for Truth.

Re:Logic (2, Interesting)

MindKata (957167) | more than 5 years ago | (#26143999)

"In either case dark matter may not be necessary at all"

I agree dark matter may not be the correct answer, but more like, the current best fit answer, given current available evidence. One concept that could explain what is going on, without the need for dark matter, is the idea of Dark Flow.

If Dark Flow can be proven, (big if?! ... Instant Nobel Prize winningly big if?!), but joking aside, if Dark Flow can be totally proven, then it would mean our idea of the universe, is simply only based on our visible part of the universe. (Due to the limit of how far we can see, because light can only travel so far, in the time the universe has existed). If Dark Flow really exists, then it means we are like a fish in a fish bowl, trying to make sense of the fish bowl, but unable to see beyond the bowl. (So unaware of just how much could be outside the fish bowl).

If Dark Flow really exists?, I think that would give us an awesome insight into the universe, but also an awe inspiring glimpse of just how limited our understanding of the universe may actually be?.
http://en.wikipedia.org/wiki/Dark_flow [wikipedia.org]

Re:Logic (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26143057)

Only on Slashdot will the first post be modded redundant.

Misleading Slashdot title (-1)

Anonymous Coward | more than 5 years ago | (#26142377)

The existent of dark energy hasn't been "confirmed." On the suspicion that it exists is more likely correct.

Re:Misleading Slashdot title (-1, Offtopic)

LS (57954) | more than 5 years ago | (#26142419)

Misleading Slashdot title

you're new around here, aren't you...

Re:Misleading Slashdot title (0, Offtopic)

floodo1 (246910) | more than 5 years ago | (#26142905)

Yeah, he came over here from Digg! /buh-dum-ching

Re:Misleading Slashdot title (1)

slashnik (181800) | more than 5 years ago | (#26142881)

but I thought we had a glimpse of it's fur

Article Confirms kdawson Doesn't Read Articles (5, Informative)

Anonymous Coward | more than 5 years ago | (#26142399)

Galaxy Clusters' Stunted Growth Confirms Dark Energy

"Together with earlier observations... the new data strengthen the suspicion â" but do not prove â" that dark energy is a weird antigravity called the cosmological constant that was hypothesized and then abandoned by Albert Einstein as a 'blunder' almost a century ago.

Wait, what?

Re:Article Confirms kdawson Doesn't Read Articles (-1, Offtopic)

dsanfte (443781) | more than 5 years ago | (#26142471)

tagged !confirmed. Btw, is there a more general tag for headline hyping?

Re:Article Confirms kdawson Doesn't Read Articles (0, Offtopic)

Manuel M (1308979) | more than 5 years ago | (#26142929)

tagged !confirmed. Btw, is there a more general tag for headline hyping?

badheadline is even more general than that, and I think it's quite appropriate.

Re:Article Confirms kdawson Doesn't Read Articles (5, Informative)

osu-neko (2604) | more than 5 years ago | (#26143073)

Dictionary: confirm

1. To support or establish the certainty or validity of; verify.
2. To make firmer; strengthen

See definition 2. Incidentally, in science, "confirm" always means 2. Certainty is impossible to establish using the scientific method. An experiment that produces the expected result confirms the theory, but certainly does not prove it.

Re:Article Confirms kdawson Doesn't Read Articles (1)

Hal_Porter (817932) | more than 5 years ago | (#26143645)

What about the scientific consensus though? CNN tells me that the scientific consensus is that Global Warming is real.

Re:Article Confirms kdawson Doesn't Read Articles (0, Offtopic)

C0vardeAn0nim0 (232451) | more than 5 years ago | (#26143887)

global warmin is real. the CAUSE of global warming is debatable.

Re:Article Confirms kdawson Doesn't Read Articles (1)

MaskedSlacker (911878) | more than 5 years ago | (#26143665)

I hope you don't try to evaluate regexps in your head.

1) ((To support) || (establish) ) ( (the certainty) || (validity of) ); verify.

Number one works--to support the validity of.

Re:Article Confirms kdawson Doesn't Read Articles (2, Insightful)

firmamentalfalcon (1187583) | more than 5 years ago | (#26144039)

Isn't dark energy a general name for whatever it is that causes our universe do things that aren't explained by our equations?

So I guess this confirms Dark Energy even more because it invalidates even more equations than before. So it isn't the old equations that are wrong; it is only because part of the equation does not include variable D.

Fox Hunt? (5, Funny)

GradiusCVK (1017360) | more than 5 years ago | (#26142413)

Adam Riess of Johns Hopkins and the Space Telescope Science Institute, said: 'If this was a fox hunt and dark energy was the fox, I think they have closed off another escape route. But there is still a lot of terrain left for the fox, and we've seen little more than a glimmer of fur.'

Hmmm, not sure if I follow, someone please correct me if I'm wrong, but it sounds like what he's saying is that if this were a highway chase and dark energy were a criminal's car, then they have placed a police car as a barracade in the way... but there's still a lot of exits around, and we've only seen a glimmer of chrome?

Re:Fox Hunt? (4, Funny)

Thanshin (1188877) | more than 5 years ago | (#26142499)

You got it wrong, he wasn't talking about fox, the animal, but about Fox Mulder.

Dark energy is what took his sister to a distant galaxy and that distance is growing every day. The FBI are closing escape routes, but the dark energetic abductor has still much galaxy to run.

The glimer of fur thing must be a reference to the sister.

Re:Fox Hunt? (4, Funny)

TapeCutter (624760) | more than 5 years ago | (#26143417)

"The glimer of fur thing must be a reference to the sister.".

NASA confirms it! [nasa.gov] .

Re:Fox Hunt? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26142855)

Haha, come on mod's that's kinda funny.

I tagged this stupidanalogy

Re:Fox Hunt? (2, Informative)

Xest (935314) | more than 5 years ago | (#26143087)

Seeing as fox hunting involves a bunch of extremely rich (inherited rich, never worked a minute in their life rich) people with a taste for animal blood riding horses around, sending a small army of dogs after a fox and ripping it to shreds just for the sake of it, I think your analogy is actually better.

I'm not sure there are many rich physicists out there that ride horses round their labs wearing red jackets and joppers, nor am I sure how dogs would help track down dark matter but I am at least sure it's probably not a good idea to let a bunch of dogs try and rip some dark matter to shreds when we do find it.

Not exactly (1)

Kupfernigk (1190345) | more than 5 years ago | (#26143969)

He was saying that they need someone named John Peel on the project to make any progress, along with his assistants Ruby, Ranter, Royal,Bellman and True. (Those who are thinking of the public school educated DJ rather than the Cumberland farmer should refer to this page [sterlingtimes.org] though I disagree slightly with the version of the song there.

Obligatory xkcd (4, Funny)

RuBLed (995686) | more than 5 years ago | (#26142449)

It's not dark energy, it's your mom [xkcd.com] !

^2 (0, Funny)

Anonymous Coward | more than 5 years ago | (#26143329)

> It's not dark energy, it's your mom!

That's what she said!

The Ultimate Fate of the Universe (5, Informative)

CodeBuster (516420) | more than 5 years ago | (#26142453)

If that is true, the universe is fated to empty itself out eventually, and all but the Milky Way's closest neighbors will eventually be out of sight.

Not only that, but depending upon the key value of state w, the ratio between dark energy pressure and its energy density, if the value of w is less than -1 then the universe will eventually be pulled apart as the rate of expansion begins to accelerate towards infinity. First the nearest galactic clusters will fade from view, then the nearest galaxies in our cluster, then the stars in our galaxy. Finally, approximately three months before the end, the solar system itself will become gravitationaly unbound, in the last minutes stars and planets will be torn apart, and finally, an instant before the end of everything individual atoms and their subatomic pieces will be ripped into ever smaller pieces until there is nothing left (i.e. the last bits just wink out of existence). The end, if it were to occur in this way, is around 50 billion years, or approximately 3.8 times the current known age of the universe, into the future. This hypothesis is known colloquially as the Big Rip [wikipedia.org] .

Re:The Ultimate Fate of the Universe (5, Insightful)

ChangelingJane (1042436) | more than 5 years ago | (#26142675)

Until they find yet another force we didn't know about, and the model changes again... Hopefully this will keep happening over and over, because all of these different end-of-the-universe theories are morbidly fascinating.

Like the man said... (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#26142769)

...Never cross the streams.

Re:The Ultimate Fate of the Universe (1)

MRe_nl (306212) | more than 5 years ago | (#26143845)

"And AC said: "LET THERE BE LIGHT!" And there was light--"

Timescales (Re:The Ultimate Fate of the Universe) (3, Informative)

ErkDemon (1202789) | more than 5 years ago | (#26143933)

That timescale may not take into account the additional effects of the expansion on local rates of timeflow. You can have an extended version of the Hartle-Hawking bubble in which there's a larger conservation law between massenergy and spacetime, and the local rate of timeflow goes towards infinity as the background massenergy density goes towards zero (think of this as the inverse of the gravitational time dilation efect). [wikipedia.org]

In that sort of model, the Hubble redshift is only proportional to the expansion ratio as a first approximation (whose range is roughly analogous to the range within the elastic limit of a spring).
There then becomes an upper limit to the possible size of the universe, that corresponds to the total (finite) massenergy contained within it. As we approach that limit, things unravel. The resulting increase in atomic instability can then be expressed as an effect of decreased nominal inertial mass due to the reduced background field strength (nuclear stability is a function of inertia).

But a decrease in local inertia also corresponds to an increase in the local rate of timeflow. The absolute end of the universe then represents a point in time where the nominal rate of timeflow is infinite (although, by then, there's nothing left to measure it with), so the period at which the universe nominally ends, measured in "insider-time", is in the infinitely far future. Okay, so its not quite infinitely far away, because the last proton evaporates at a finite time, but the timescale is effectively infinite to most intents and purposes, as far as we're concerned.

The advantage of this form of time-scaling is that it tidies up the Hartle-Hawking model - it allows the "equator" of the H-H bubble to represent the apparent end of the universe for insiders, and to be totally smooth. This removes the messiness that we'd otherwise tend to get when the bubble reaches its maximum size and parts of it start to contract. Contraction implies reversed entropic timeflow, so the HH bubble has a problem in that an observer living through the expansion-contraction region might see some mightily strange things going on. Some regions might be seen to be ageing in opposite directions to others. But if the interior rate of timeflow goes to infinity at the equator (as the angle of "proper" time approaches the angle of axial time, and its angle with the radial time-parameter 'a' tends to 90 degrees), then interior detail is totally erased at the equator, and the apparent inconsistencies with observerspace physics disappear ... you can never survive a transition past the equator, and the event-meshes of each hemisphere are isolated from each other by the equatorial evaporation zone.

The expansion and contraction phases of the bubble then both effectively belong to two separate universes, both of which think they're expanding, and both with opposite senses of proper time. The equatorial evaporation zone keeps both sets of causalities isolated, and prevents nasty messy phase transitions where the two "worlds" collide.

If we look at the geometry of one hemisphere of the extended H-H bubble model, and we use axial time as our reference, or we take a tangent to a given zone and extend that zone's local sense of proper time as as a straight line to give us our time-reference for the rest of the bubble, then what we end up with is a description that seems to describe a "Big Rip" at a definite, finite time. Our projection tells us that the universe contents speed up and start to "fizz and whizz" at an increasing rate before finally disappearing altogether. But to physics performed inside that universe, things aren't hotting up, they're cooling down -- instead of matter mysteriously evaporating after few billion years, it's decaying more conventionally over rather vaster timescales.

Cosmological timescales and reference systems

The thing one has to be careful of with cosmological descriptions is that they often use geometrically-convenient projective timescales that doesn't necessarily correspond (even approximately) to actual elapsed time, except over small regions. The nominal separations in the description then depend on the angle that you choose to use for your projection of the hypersphere. For convenience, we often take "here-and-now" as a reference and then define times by placing an imaginary ruler against the hypersphere so that it touches the corresponding point on the surface, and aligns well locally with proper time in the surrounding patch ... and then we read off the distances for other locations by taking a line from that location perpendicular to the "ruler", and then taking the ruler reading. It's a convenient method, since it allows us to label regions without taking into account variability in proper time across the hypersphere - if our cosmological model changes, the reference system will often still use the same numbers. But the cost of this deliberate insensitivity to the choice of physical model is that our timescale numbers deliberately don't take into account environmental variations in timeflow. Close to the "here-and-now", where our "ruler" is effectively parallel to the hypersphere surface that it rests against, the ruler readings and the actual timeline distances correspond pretty well. But as we move to very different parts of the universe's history, the surface curves away from the "ruler", and you get rescaling effects due to the projection of surface detail against an angled reference system (think Mercator projection [wikipedia.org] ). When you also bear in mind that background mass-density has an effect on timeflow, and that in the "Big Rip" scenario, that background density nominally sweeps all the way from ~infinity to zero, then it should be apparent that when we describe the date of a hypothetical Big Rip using this artificial projective dateline, the nominal dates aren't compelled to correspond to any physical calendar. The assigned dates have geometrical significance, and mean something to cosmologists, but readers shouldn't assume that they're assumed to correspond to actual elapsed time. When you read descriptions of what happened in the "first few seconds" after the big bang, or what might happen in the "last few minutes" of the universe, you have to bear in mind that we aren't necessarily talking about "normal" seconds and minutes here, and that in cosmology, the projective mapping between "descriptive" seconds and "real" seconds can be extreme ... in cases like this, actually infinite.

Re:Timescales (Re:The Ultimate Fate of the Univers (3, Funny)

iamnothere900 (1098065) | more than 5 years ago | (#26147103)

I honestly can't tell if you're incredibly insightful or just adding words after one another. My brain hurts either way.

blunder (5, Interesting)

sstory (538486) | more than 5 years ago | (#26142489)

(Sigh). Everytime I see a story about the cosmological constant I have to see the obligatory "that dark energy is a weird antigravity called the cosmological constant that was hypothesized and then abandoned by Albert Einstein as a 'blunder' almost a century ago." as if Einstein was so smart he predicted dark energy 100 years ago. No. He put a term in the equation to stabilize the universe, which was then thought to be static, against gravity. Then it turned out the universe wasn't static, it was expanding. That was the blunder. If there's an outward force, as there now seems to be, you'd put a term in the same place. But it's based on new data. I'm sick and tired of the "Aha! Einstein was right all along and he didn't even know it!" comment that has to be stuffed in every cosmological constant story these days.

Re:blunder (5, Funny)

reallyjoel (1262642) | more than 5 years ago | (#26142657)

Bah, you're not so smart, who do you think you are, Einstein?

Re:blunder (0)

Anonymous Coward | more than 5 years ago | (#26146091)

He's Stephen Hawking, bitch!

Re:blunder (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#26142745)

I think you're annoyed only because you're trying hard to be annoyed. As an exercise, try to rewrite the statement that "the same term was hypothesized by Einstein" in a way that you like, and I think you'll realize that it's already pretty good the way it is written. Maybe an improvement would be to write "was hypothesized with the wrong sign".

Re:blunder (4, Informative)

ErkDemon (1202789) | more than 5 years ago | (#26144315)

No, the earlier poster is right, as far as theory is concerned, Einstein's "Cosmological Constant" and "Dark Energy" perform different functions.

Einstein invented his "repulsive" effect to explain why the universe was static, and neither expanding or contracting. Unfortunately for Einstein, Hubble's redshift observations a few years later indicated that the "static" property of the universe that Einstein's CC had been invented to reproduce within GR, wasn't correct.

Dark energy was invented to explain why, when we take an expanding universe model decribed with general relativity, and try to compare it with reality, the numbers still don't appear to match up with the theory.

----

Einstein's Cosmological Constant was an attempt to force GR to produce a wrong answer that Einstein (at that time) happened to think was a mathematically elegant one. The system seemed to describe a universe that would have to be expanding or contracting, and Einstein said ... "Well we know that THAT has to be wrong, so to make things nice and static, I'll write in an additional term for a necessary effect that I've just made up, that would exactly cancel the large-scale effect of gravity ... "

The motivation, function, and results for the two hypothesised effects are different. Both effects are repulsive, and both of them are essentially "made up" as accounting fudges without any deeper physical or philosophical justification, to force a theory that generates one result to generate a different result that we like better, but that's about all they have in common.

They're really different animals. Dark energy isn't an effect designed to explain why the universe is static. However, if you're inventing an arbitrary effect to bring your theory into line with experiment, the awkwardness of admitting that you're basically making stuff up to force the answer you want is reduced if you can claim some "provenance" for the idea, and present your "new" effect as if it's a logical historical development of an earlier idea by a Famous Physicist. That adds an air of legitimacy.

But if we think that the DE idea is any good, then the idea that DE is a historical extension of Einstein's CC is phoney. Einstein's CC is dead and buried. The only way that DE might turn out to be able to claim descent would be if DE turns out to be a rotten idea too, in which case we could say that there's a common theme running through both bad ideas. :)

But if the Dark Energy idea is good, then it's really not "bringing back Einstein's cosmological constant in revised form".

Re:blunder (0)

Anonymous Coward | more than 5 years ago | (#26147149)

Try again to rewrite it, but this this it has to fit in a single short sentence.

In a textbook you might want to maximize clarity, but in a newspaper you want to maximize efficiency, which is clarity-divided-by-length. All these attempts to increase clarity from 90% to 99% by writing a novel miss the point. Readers would rather move on with the galaxy cluster story and can Google for "Einstein cosmological constant" if they're interested to know more about it.

Re:blunder (1)

martin-boundary (547041) | more than 5 years ago | (#26142989)

There's a few annoying science memes like that. The one that always makes me cringe is when people claim that the idea of atoms in physics originated with the Greek philosophers.

Re:blunder (0)

Anonymous Coward | more than 5 years ago | (#26143163)

So you don't follow the stories of Democritus?
http://en.wikipedia.org/wiki/Democritus#Atoms_and_the_void
I agree that atomic theory was developed SEPARATELY, and thus does not ORIGINATE there - atomic theory, like so many scientific theories, has many origins that eventually coalesced and accumulated. This is simply the first known recorded case of "an atomic theory" resembling the modern one in the slightest.

Or are you saying there was an earlier case? If so I'd like to know, because my knowledge of scientific history isn't that great.

Re:blunder (2, Insightful)

martin-boundary (547041) | more than 5 years ago | (#26143445)

Democritus didn't have an "atomic theory", what he had was merely metaphysical speculation.

With the technology available in his time, not only was it impossible for him to verify atomism, but in fact if he had tried to do so experimentally, then the only reasonable conclusion would have been that atomism is highly unlikely, since matter can easily be subdivided indefinitely to the limit of visual perception. As such, steadfastly maintaining the truth of atomism would mark him out as a crackpot nowadays, although in his time the standards of rigour were of course much different.

Democritus' atomism was an ancestor of atomic theory in the same sense that "a broken clock is right twice a day".

Re:blunder (1)

AvitarX (172628) | more than 5 years ago | (#26144899)

I can't think of one, but it seams feasible there is an experiment to test "atomic" theory that does not involve visibility.

Wasn't there a doctor/gravedigger that theorized invisible tubes connecting arteries to veins, and yet could not see them?

I would say that the test would be subdividing until non-existance (by ancient world standards) and devising tests if something fundamentally the same (perhaps flammability) was there.

Re:blunder (1, Informative)

Anonymous Coward | more than 5 years ago | (#26145555)

You claim is not correct. The Greek atomic theory attributed to Democritus and his peers was more than metaphysical speculation. It was based on observations that matter could be divided, rings would wear from fingers and food could be smelled from a distance. Therefore stuff must be made of really small parts. That was the gist of their "theory". It's not as sophisticated as quantum mechanics but it's not purely metaphysical speculation either. By your argument all of Ancient Greek science was just metaphysical speculation.

Re:blunder (0)

Anonymous Coward | more than 5 years ago | (#26143171)

I took that bit to mean that Albert Einstein was smart enough to have realised it was an ugly kludge of an idea a century ago and modern physics still hasn't caught up to him.

Re:blunder (1)

khallow (566160) | more than 5 years ago | (#26146531)

I'm sick and tired of the "Aha! Einstein was right all along and he didn't even know it!" comment that has to be stuffed in every cosmological constant story these days.

Still it is mostly accurate anecdote. The only real problem with it is that it gets overused.

Huh, confirming theories... that's a new one (2, Interesting)

wolfie123 (1331071) | more than 5 years ago | (#26142541)

And I who thought that theories cannot be confirmed by real-world observations, only supported. ...as the blurb also mentions, actually.

Needs a better headline & summary (-1, Redundant)

floodo1 (246910) | more than 5 years ago | (#26142719)

Horrible headline & summary :(

A new study of 86 galaxy clusters in the early universe has provided independent confirmation of the existence of dark energy

and quotation:
the new data strengthen the suspicion â" but do not prove

The summary makes it sound like they actually proved that dark matter exist, not simply added to the inference of it's existence :(

Re:Needs a better headline & summary (5, Informative)

osu-neko (2604) | more than 5 years ago | (#26143107)

The summary makes it sound like they actually proved that dark matter exist, not simply added to the inference of it's existence :(

Science is not in the business of making provable claims. It's impossible to prove anything using the scientific method. Science makes falsifiable claims, and any experiment that fails to falsify them confirms the theory, but most certainly does not prove it. An experiment that "confirms" a theory is one that produces a result compatible with that theory under circumstances where a different result would have falsified it. Confirmation merely strengthens a theory, it cannot ever prove it.

More Journlistic Integrity (-1, Redundant)

Kashell (896893) | more than 5 years ago | (#26142739)

Galaxy Clusters' Stunted Growth Confirms Dark Energy ...the new data strengthen the suspicion â" but does not prove... Ah.

In other news, Einstein's grave is... (2, Funny)

NinthAgendaDotCom (1401899) | more than 5 years ago | (#26142763)

...reportedly spinning and expanding by a factor of 50 as he realizes he shouldn't have called it a blunder. :-)

We have much to learn (2, Insightful)

little1973 (467075) | more than 5 years ago | (#26142829)

I believe that our knowledge about the universe is quite limited. I can imagine the scientists of the future will laugh about how we could seriously consider dark matter and dark energy. I think it is quite possible that gravity behaves differently over great distances (and I know about the latest "evidence" of dark matter where the dark matter was "imaged" but it is an indirect evidence, there may be other things up in the universe's sleeve which causes this).

I believe there will be another Einstein who will shed light upon this "mistery" and everything will be simple again.

Re:We have much to learn (-1, Redundant)

floodo1 (246910) | more than 5 years ago | (#26142915)

Way to contribute Nostradamus!

Re:We have much to learn (1)

blad3runn69 (1022135) | more than 5 years ago | (#26143187)

'I believe there will be another Einstein who will shed light upon this "mistery" and everything will be simple again.' well put. what worries me is it hasn't happened even with the internets...?

Re:We have much to learn (1)

Thanshin (1188877) | more than 5 years ago | (#26143885)

I believe there will be another Einstein who will shed light upon this "mistery" and everything will be simple again.

Simple again?

Whan was the last time everything was simple?

I'm thinking caveman's "If you don't know how something works, it must be a spirit".

Heim Theory predicted and explained this (-1, Troll)

Zdzicho00 (912806) | more than 5 years ago | (#26142853)

This anomaly is not due to mysterious "dark energy", simply "mainstream" understanding of gravity is not complete.
Heim Theory predicted and explained this in 1950s:

http://www.engon.de/protosimplex/posdzech/px_g_gravi1e.htm [engon.de]
Read more here:
http://en.wikipedia.org/wiki/Heim_theory [wikipedia.org]
/Joss

evolution baby (1)

blad3runn69 (1022135) | more than 5 years ago | (#26142985)

einstein was a goddam genius. the world needs another einstein. Maybe we could clone him ;P

Re:evolution baby (1)

blad3runn69 (1022135) | more than 5 years ago | (#26143017)

I think there are bits of his brain floating around somewhere (futurama?) ;P

Link to full paper (5, Informative)

Mwahaha (824185) | more than 5 years ago | (#26142997)

For those interested the full paper is here [arxiv.org] . Apart from a couple of cosmological parameters they don't really improve previous estimates. It's still nice though that all the parameters agree very well with the previous (CMB + Supernova 1a) data with a completely independent method, hence the confirmation talk. I think though if there had been disagreement our understanding of clusters would have been blamed first. So in some senses this confirmed the current cluster models more than the cosmological constant, but that's not as 'sexy'!

Re:Link to full paper (1)

blad3runn69 (1022135) | more than 5 years ago | (#26143041)

hah sexy. so cool the numbers add up. Truly brilliant stuff. thanks for the link :)

Matter and Energy...or not? (5, Insightful)

ghostdoc (1235612) | more than 5 years ago | (#26143031)

So let me get this straight...we have Dark Matter because there's not enough gravity within a galaxy to explain the observations, and Dark Energy because there's too much gravity between galaxies to explain the observations.

Surely Occam's Razor comes into play here? Surely it's obviously simpler to say 'we've got the maths wrong for gravity beyond solar system scale' and start again at the chalkboard?

Re:Matter and Energy...or not? (0)

blad3runn69 (1022135) | more than 5 years ago | (#26143063)

gravity is gravity on a quantum or universal scale isn't it?

Re:Matter and Energy...or not? (0)

Anonymous Coward | more than 5 years ago | (#26143141)

Not according to Bob lazar! ;)

Re:Matter and Energy...or not? (1, Insightful)

Zdzicho00 (912806) | more than 5 years ago | (#26143491)

Heim Theory got Simple explanation for that. Every field got "field mass" associated with it:
http://www.engon.de/protosimplex/posdzech/px_g_gravi1e.htm [engon.de]

Because of equivalence of mass and energy Heim says there must also exist a field mass of the field energy of each field. However in case of gravitational field this results in a secondary (very weak) additional gravitative source because a field mass possesses its own gravitational field.
In a volume V0 there is mass which may be distributed in any kind. This mass is producing a gravitation effect, as it can be described with Newton's approximation. Now Heim says that to the energy of this gravitational field corresponds its own field mass. This field mass again produces a second additionally gravitational field which is very weak. Again this field possesses its own field mass which produces a field. So you receive an infinite series, which however converges very fast against a calculable limit value.
The whole description results in a short mathematical description for a corrected gravitation law, which corresponds with Newton's gravitation law within the observable area of space. However for very large distances it will provide completely different results. As you can see in the illustration below for very long distances gravitation will produce a weak repulsing force which will only exist if a mass is moving toward the center of the gravitational field. Among other things the phenomenon of the cosmic red shift can be explained now as a gravitational effect.


/Joss

Re:Matter and Energy...or not? (0)

Anonymous Coward | more than 5 years ago | (#26143509)

Feel free to propose alternative theories.

That being said, Occam's razor isn't always obeyed by nature, either. Sometimes, things really ARE stranger than you might think...

Re:Matter and Energy...or not? (4, Insightful)

Kjella (173770) | more than 5 years ago | (#26143533)

Surely Occam's Razor comes into play here? Surely it's obviously simpler to say 'we've got the maths wrong for gravity beyond solar system scale' and start again at the chalkboard?

Well, from what I've understood adjusting the constant of gravity would explain some things but would make other predictions incorrect again. All in all, dark matter / dark energy is causing less headaches than the opposite, so unless you can pair it off with some other theory to make the world right again it won't get accepted.

Re:Matter and Energy...or not? (0, Flamebait)

EmagGeek (574360) | more than 5 years ago | (#26143777)

Welcome to "Science by Consensus."

Re:Matter and Energy...or not? (3, Interesting)

jandersen (462034) | more than 5 years ago | (#26143897)

Surely Occam's Razor comes into play here? Surely it's obviously simpler to say 'we've got the maths wrong for gravity beyond solar system scale' and start again at the chalkboard?

Which is, in effect what we are saying. However, it makes little sense to simply scratch the whole, current understanding of the world and start over; introducing an assumption that gravity behaves differently outside a certain distance begs the question why it should be so, and we don't have any compelling answer to that.

My own favourite, which admittedly comes out of thin air, is that negative gravity corresponds to negative mass. If you look at the classical equation as a rough approximation, you'll see that a negative mass should repel a positive mass, but attract another negative mass. Intuitively this seems to potientially explain the "dark energy" phenomenon, and it might explain how, at the beginning, mass seems to have been created from nothing - perhaps an equal amount of positive and negative mass was created, so that mass was preserved, in total, and then it exploded apart. How about that for an explanation?

Re:Matter and Energy...or not? (1)

Burnhard (1031106) | more than 5 years ago | (#26144809)

I have to agree with ghostdoc. IANAP but my instinct tells me that rather than create a new entity and adding it into current orthodoxy to explain difficult facts, one should examine current orthodoxy. The theory of Epicycles was a pretty good explanation of the movements of heavenly bodies in the Ptolemaic system, but quite wrong. I'm reminded of quite a nice quote:

"Really new trails are rarely blazed in the great academies. The confining walls of conformist dogma are too dominating. To think originally, you must go forth into the wilderness."

We need more Scientists in the wilderness.

Re:Matter and Energy...or not? (4, Insightful)

Abcd1234 (188840) | more than 5 years ago | (#26146515)

I have to agree with ghostdoc. IANAP

Obviously. If you were even passingly familiar with the area, you'd realize that a) people *have* been re-examining the orthodoxy (see MOND, among other things), because, you know, some scientists are as smart as you (or perhaps even smarter) and realize that it's an interesting area of research, and b) no one has found an alternate theory that explains the current set of observations (see the Bullet Cluster, and some even more recent results).

Honestly, what is it with laymen who somehow believe that *they* have some insight into an area that those who've been studying it their entire lives do not?

Re:Matter and Energy...or not? (0)

Anonymous Coward | more than 5 years ago | (#26144947)

No...no it isn't. All other known theories either do not work or have requirements that need further observations. In fact, Occam's Razor demands that old theories be patched first before considering alternatives.

Space time questions (0)

Anonymous Coward | more than 5 years ago | (#26143219)

From someone whose only astronomy education is from popular science:

- is there an assumption that spacetime is smooth? Clearly, areas with concentrations of matter will weigh down on spacetime, like objects on a blanket. What if the blanket isn't smooth, or less so than in the areas where matter exists regularly?

- could there exist anything on the underside of spacetime, which effectively causes the antigravity effect? Could black holes link the overside to the underside, effectively causing acceleration through the transfer of matter or energy from our side of spacetime to the other side?

Alternative explanation (4, Insightful)

EdibleEchidna (468353) | more than 5 years ago | (#26143363)

Instead of proving the existence of Dark Energy, perhaps what this finding really does is prove that our models are wrong.

I often wonder if we're looking in the wrong place for an explanation...flaws in our cosmology sound more plausible to me than weird forms of matter and energy.

Re:Alternative explanation (2, Interesting)

cnettel (836611) | more than 5 years ago | (#26143779)

Well, if we are able to go about it in a totally different way, that the dark matter/energy estimates weren't ad hoc-adjusted to fit, and we still see that those estimates fit, it means something. It might be something else, including a weirdness in gravity, but overall the data fits well with something that is quite similar to matter.

Re:Alternative explanation (1, Insightful)

Anonymous Coward | more than 5 years ago | (#26144945)

Instead of proving the existence of Dark Energy, perhaps what this finding really does is prove that our models are wrong.

Those statements are semantically equivalent. Scientists aren't in the business of saying whether X or Y exists, leave that to the philosophers. A scientist can say that "X is a useful way to model the world", but Y might be another way to look at it that ends up with more or less the same math. And then when our tools are good enough to try and tell the difference between X and Y (if there even is one!) we go probe it and move on.

Scientists *model* reality, not discover or declare it.

Re:Alternative explanation (1)

Abcd1234 (188840) | more than 5 years ago | (#26146633)

I often wonder if we're looking in the wrong place for an explanation...flaws in our cosmology sound more plausible to me than weird forms of matter and energy.

Yes, because no one has been looking in other places, say modified Newtonian gravity, for alternative explanations...

The real problem is that no one has come up with an alternative theory which both excludes dark matter/dark energy while simultaneously explaining all current observations.

Re:Alternative explanation - new 4D math (1)

sweetser (148397) | more than 5 years ago | (#26146885)

A list of no-see-'ems in physics:

Dark energy
Dark matter
The Higgs boson

My work unifying gravity with the three other forces of Nature suggests that if done right, we get new math to describe how gravity works. All three problems will politely disappear in a few calculations on paper.

Here are 4 things that work great for real and complex numbers: a robust derivative, commuting, visualization, and many connections to group theory. If we can these 4 in 4D, then the major problems in physics will be resolved.

Tensors are not enough. They have addition and its inverse subtraction, but not multiplication and its inverse division. Only 4D tensors could come with division by being isomorphic with quaternions. This would eliminate ALL work on strings.

No one can visualize 4 spatial dimensions. We can watch 3D animations. I have written the software to do so (quaternions.sf.net). Move from Descartes static analytic geometry to dynamic analytic animations. Weird and wonderful things happen with math in motion.

Feel free to email me with questions. Lots of YouTube videos available.
Doug Sweetser
sweetser@alum.mit.edu

Dark energy (0)

Anonymous Coward | more than 5 years ago | (#26143477)

Dark energy = all the photons that are on their way from whatever source to whatever destination. The universe is full of them. You don't see them unless they hit your retina. Doesn't mean they're not there. Can you "see" photons moving away from you? :)

Yuo Fa1l It? (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#26143649)

Wasn't on Steve's 4osts. Therefore 4chieve any of the for the record, I

A different theory for stunted growth (-1)

Anonymous Coward | more than 5 years ago | (#26143855)

We all know that masturbation stunts your growth, so the universe must be masturbating. You want proof? What do you think the "milky way" is?

here is a thought (0)

Anonymous Coward | more than 5 years ago | (#26145459)

maybe just maybe the need for dark energy is simply the evidence of our model of physics being incorrect and relativity isn't where its at after all. Maybe our scientists are just so in love with it that they won't let it go despite observations that are inconsistent and so they invent dark matter/energy instead.

Just a Question (1)

Nom du Keyboard (633989) | more than 5 years ago | (#26145779)

all but the Milky Way's closest neighbors will eventually be out of sight

Wouldn't that only happen if they were receding at greater than the speed of light? Otherwise the light would still get to us, just being dimmer because of the increased distance.

So does that mean... (1)

PunditGuy (1073446) | more than 5 years ago | (#26145839)

that a galaxy that was far, far away in the 70s is now far, far, far away?

"we've seen little more than a glimmer of fur." (1)

GodfatherofSoul (174979) | more than 5 years ago | (#26146071)

Probably because you spend all your nights in an observatory staring at the sky. I'd get out to the bars more and feed shots to some sorority chicks on rush week.

!Confirmed (1)

DynaSoar (714234) | more than 5 years ago | (#26146187)

"But there is still a lot of terrain left for the fox, and we've seen little more than a glimmer of fur."

That's a damn stretch from "confirms", especially coming from a primary in the research.

All the study confirmed was that early galaxies appear to have behaved in a manner as though gravity were different or affected by another force. It doesn't mean they did, it means their observations can be taken that way. It doesn't mean there was dark energy, it means they don't seem to act as though they not affected by gravity then as they would be now. The data support the delta-g (gravity changing over time) theory as much as dark energy. Other data makes it less likely (clumpiness in these an similar observations), but my argument is with the difference between the headline and the substance in TFA. If NYT is going to report everything as though it were common news, with the emphasis on spectacularism for the sake of sales, they should respect what science is supposed to be like (ie. accurate and objective to the extent possible) and not touch it.

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