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346 comments

well no kidding (4, Funny)

User 956 (568564) | more than 8 years ago | (#14488848)

According to new research the strength of dark energy may be very different now than it was when the universe was young.

Indeed. Begun, this clone war has.

Re:well no kidding (2, Funny)

gbobeck (926553) | more than 8 years ago | (#14488896)

Jedi! Their Order is a fading light in the dark. Corrupt and arrogant, they must be punished. The Jedi shall fall.

Re:well no kidding (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#14488933)

EU to Officially Induct USA into EU

16/01/2006 Yur O Trasch

In his latest speech outlining his administration's latest plans to deflect his failures, French President Jacques Chirac focused on his grand initiative to make the USA a permament member of the EU, although with no voting privilges.

Chirac said that rather than try and recreate all the various technologies that the USA has, such as Googe, Microsoft, Intel,GPS, etc., making them a permanent member of EU will give all Europeans access to these technologies without spending money that could be better spent on idle French farmers or 45 year old German retirees living in Califonia.

"What Frenchman cannot hold his head high when using Google to search the internet...as long as he doesn't search for Nazi memorabilia", said Chirac. "What Belgian will not kiss the EU flag when he realizes that GPS is now a European technology?"

The ambitious project is still in the early stages of discussion and has not yet been presented formally to the USA.

so... (1, Funny)

Anonymous Coward | more than 8 years ago | (#14488849)

it's not as dark as we thought it was?

Europe (-1, Troll)

Anonymous Coward | more than 8 years ago | (#14488850)

Europe to Officially Induct USA into EU

16/01/2006 Yur O Trasch

In his latest speech outlining his administration's latest plans to deflect his failures, French President Jacques Chirac focused on his grand initiative to make the USA a permament member of the EU, although with no voting privilges.

Chirac said that rather than try and recreate all the various technologies that the USA has, such as Googe, Microsoft, Intel,GPS, etc., making them a permanent member of EU will give all Europeans access to these technologies without spending money that could be better spent on idle French farmers or 45 year old German retirees living in Califonia.

"What Frenchman cannot hold his head high when using Google to search the internet...as long as he doesn't search for Nazi memorabilia", said Chirac. "What Belgian will not kiss the EU flag when he realizes that GPS is now a European technology?"

The ambitious project is still in the early stages of discussion and has not yet been presented formally to the USA.

Lets hope.. (5, Funny)

Anonymous Coward | more than 8 years ago | (#14488852)

..that someone shreds some light on the matter.

"I too, sense a disturbance in the Force"

And in Related News... (3, Funny)

SkuzBuket (820246) | more than 8 years ago | (#14488855)

Significant amounts of this so-called, "Dark Energy" have been measured around a certain Redmond, WA campus.

Eat Meat (-1, Offtopic)

Anonymous Coward | more than 8 years ago | (#14488859)

Eat Me At Joe's

It is changing, but we don't know which way (2, Interesting)

tod_miller (792541) | more than 8 years ago | (#14488861)

It doesn't say if it gets stronger or weaker..

wtf

Re:It is changing, but we don't know which way (1)

heatdeath (217147) | more than 8 years ago | (#14488928)

It doesn't say, but if it's brighter than expected, that means that the rate of accelerating is becoming greater.

Re:It is changing, but we don't know which way (2, Insightful)

grimJester (890090) | more than 8 years ago | (#14488955)

Since dark energy acts opposite to gravity, I'd assume more would mean brighter visible GRBs. Also, we have no good explanation for inflation [wikipedia.org]. Could this be it? Speculating even further, if dark energy is weakening the universe might not expand forever.

That's a pretty bold statement... (4, Insightful)

numLocked (801188) | more than 8 years ago | (#14488868)

...considering no one even knows if dark energy EXISTS.

Re:That's a pretty bold statement... (0, Flamebait)

AoT (107216) | more than 8 years ago | (#14488973)

I am still confused why we need dark energy AND dark matter. Seems like we are missing something. I would give it 20 years or so before they figure out that both those damn things would just cancel themselves out.

And one other thing, gravitrons. If there are really particles of gravity then they would have mass and thus create more gravitrons in an endless cycle.

Of course I have not kept up with all this wierd new physics crap lately, I figured that by the time i learned all of the terminology the theories would change.

Re:That's a pretty bold statement... (2, Interesting)

dogbreathcanada (911482) | more than 8 years ago | (#14488993)

The science (and theories) don't necessarily change ... they evolve. Dark Matter and Dark Energy are "necessary" because there's not enough visible matter in the universe to account for the size and expansion of the universe.

Dark Matter and Dark Energy are "necessary"... (-1, Flamebait)

Killall -9 Bash (622952) | more than 8 years ago | (#14489308)

...because scientists would rather mentally masturbate about phenomenon that we have yet to observe or measure directly than admit that their understanding of space time may be fundimentally flawed. Everyone laughed at Einstein's cosmological constant, but now its supposed to be credible after a name change and a bad 90's sci-fi makeover?

Re:That's a pretty bold statement... (1, Interesting)

spectrumCoder (944322) | more than 8 years ago | (#14489003)

There are many massless particles in physics. Photons, for instance.

Note that it makes just as much sense to talk about gravity waves as it does to talk about gravity particles, and no one assumes waves have to have mass.

Dark energy, dark matter and gravitons are all theoretical concepts postulated to help make the world make sense to physicists. But that doesn't mean they exist.

Re:That's a pretty bold statement... (0)

Anonymous Coward | more than 8 years ago | (#14489133)

Who said photons have no mass?
Where did you learn your Physics 101? In Texas along with GW?

Re:That's a pretty bold statement... (1)

spectrumCoder (944322) | more than 8 years ago | (#14489159)

Okay, they have energy, which is effectively the same thing at the end of the day, as they possess relativistic mass by virtue of their energy. E = mc^2.

Re:That's a pretty bold statement... (0, Flamebait)

Markus Registrada (642224) | more than 8 years ago | (#14489041)

I am still confused why we need dark energy AND dark matter.

Well might you be. We need them both to prop up the Big Bang after it was falsified, over and over again, by observation. Cosmologists and astronomers have individually faced a choice, each time: ditch the only hypothesis that journals' Review Committees would allow to be mentioned in publications, or invent like crazy, ad hoc. After decades of this, the field strains under the weight of a towering edifice of pure conjecture, supported by generations of graduates and professors who know nothing else, are equipped to work on nothing else and, most importantly, dare permit nothing else to be discussed or funded.

Next time you see an astronomical press release that ends with one of the principals hoping the new observation might someday help, through some mysterious process, offer us insight into the nature of dark matter, recognize the obligation to tie the work to the guild imperative. Be glad that the telescopes and space probes are built and operated by engineers. The data they collect -- and the pretty and sometimes astonishing pictures that have led us to continue funding their work, despite all -- will someday support an actual empirical theory. In the meantime, laugh.

Re:That's a pretty bold statement... (0)

Anonymous Coward | more than 8 years ago | (#14489057)

What you say is pretty solid.

(Oh and IAAP.)

Re:That's a pretty bold statement... (5, Informative)

schwanerhill (135840) | more than 8 years ago | (#14489054)

Dark matter [wikipedia.org] is required by looking at galaxy rotation curves. Essentially, the rotation speed of galaxies is too fast given the mass that can be seen, so there must be some mass that doesn't emit light as conventional, baryonic matter does. Dark matter was first hypothesized by Zwicky in 1933 and has been well accepted throughout the astronomical community for decades.

Dark energy [wikipedia.org] is required by looking at Type 1a supernovae from the early universe. Astronomers and cosmologists use Type 1a supernovae [wikipedia.org], which have a well known intrinsic brightness (they are called a "standard candle"), to establish a cosmological distance scale and measure the expansion rate of the universe. If the universe is composed of ordinary matter and dark matter, the self-gravity of all the matter in the universe would cause the expansion rate to slow over time. A goal of these observations was to determine whether there is enough matter in the universe to stop it from expanding forever and ultimately cause it to collapse back on itself in a "big crunch."

In about 1998, the supernova observations were pinned down well enough to show that the expansion rate is actually increasing with time. Therefore, there must be some "antigravity" force that causes the expansion of the universe to accelerate. This is dubbed "dark energy."

The "cosmic energy budget" says that about 4% of the mass/energy in the universe is ordinary matter, 23% is dark matter, and 73% is dark energy. The matter and dark matter total mass is measured from observations of the cosmic microwave background [wikipedia.org].

All of this is pretty well supported by the best current observational evidence, although the physical nature of dark matter and dark energy are both poorly understood (and new observations can always change things, of course).

The new claim in the current article is that the effect of dark energy has changed over time. The fundamental problem is that the new evidence relies on gamma-ray bursts, which are not nearly as well established a standard candle as the Type 1a supernovae, so it's much harder to say with certainty what distance they are at. Note that the new claim was presented at the American Astronomical Society meeting in DC last week; it has not yet appeared in a refereed journal. (Nature news is merely reporting on the AAS presentation.) The author himself has an appropriate degree of skepticism of his claim.

(Yes, I am an astronomy grad student, although I don't do any work on cosmology.)

Re:That's a pretty bold statement... (0, Flamebait)

rodac (580415) | more than 8 years ago | (#14489424)

"Essentially, the rotation speed of galaxies is too fast given the mass that can be seen, so there must be some mass that doesn't emit light as conventional, baryonic matter does. Dark matter was first hypothesized by Zwicky in 1933 and has been well accepted throughout the astronomical community for decades."

Another "theory" could be that the original "theory" is just plain wrong.
Event: Multiple observations provably invalidate theory.
Reaction: Invent new magic error term to cover up holes in theory. Error term must in order to be efficient also have special properties of being unmeasurable, undetectable and only cause desired interactions in situations when salvage of broken theory requires it.
Solution: dark energy/matter/whatever

And they call themself scientists.

Re:That's a pretty bold statement... (0)

Anonymous Coward | more than 8 years ago | (#14489466)

Yeah,
It is no better than Doc E. E. Smith's "ether" being out there. In at least one of his space exploration Sci-fi series

Re:That's a pretty bold statement... (1)

opec (755488) | more than 8 years ago | (#14489474)

Dark matter is required by...

Please. Aether was also required to explain how photons could travel through seemingly empty space with wave-like properties... Whole lotta good that theory came out to be...

Re:That's a pretty bold statement... (1)

biraneto2 (910162) | more than 8 years ago | (#14489507)

All this make me think a lot in the scientists in 1400 and before. When a lot of people used to say based on observation that the earth should be flat. Too bad it will still take a few centuries till we can laugh of ourselves on this one. I know there is a huge difference in science now, but the idea is still the same.

Re:That's a pretty bold statement... (1)

rodac (580415) | more than 8 years ago | (#14489299)

"And one other thing, gravitrons. If there are really particles of gravity then they would have mass and thus create more gravitrons in an endless cycle."

No problem, soft scientists can just invent a new "dark gravity" explanation that will make the theories consistent.

Re:That's a pretty bold statement... (2, Funny)

rodac (580415) | more than 8 years ago | (#14489018)

Look, dark matter does exist. There is no question about it.
How else would the other theories be consistent without dark matter to accoount for any discreptancies?

Ergo: dark matter exists, since without it the theories would fail.

Re:That's a pretty bold statement... (1)

mwvdlee (775178) | more than 8 years ago | (#14489060)

That is utter crap, logically speaking.

It's like saying that 1 + 1 = 1 and there must be some magical "Dark 1" that is subtraction from the equation.
It may just be that the equation is actually 1 * 1 = 1 or 0 + 1 = 1 and the theory isn't quite right.

Usually if a theory relies on the existence of something which cannot be proven, it's the theory at fault. Not saying this is the case here since there is considerable evidence supporting the ideas of dark matter and energy, but to simply state that it must exists because otherwise the theories would be incorrect would actually imply the opposite to be true.

Re:That's a pretty bold statement... (1)

rodac (580415) | more than 8 years ago | (#14489158)

Look, it was a JOKE.

The joke was based on the fact that the primary reason for dark energy/matter to exist is that without dark energy/matter the theories are not consistent. I am sorry you did not find it funny.

Re:That's a pretty bold statement... (3, Informative)

rodac (580415) | more than 8 years ago | (#14489233)

Sigh. Ok, lets try it like this :

Physics is a science. Physics is not really a hard science in the same way as Math is a hard science. Physics is way harder science than Biology and Chemistry but still a lot softer than Math, which is the Queen of Science.

Since Physics is a "soft" science, they have "theories". Some of these theories are either incomplete, not fully understood or maybe incorrect. These theories are still very useful for Physicists, too useful too just discard just because they are not completely correct, complete or provable.
This is different from real hard science such as Math where there are no real "theories" per se and where statements that are not formally provable are worthless.

Anyway, some of these theories in Physics are to physicists too useful to just ignore just because they today are provably incorrect, or not currently provable correct which means :

There are certain theories that stipulate x + y = z.

The problem here is that there are legions of observations that can not be explained using that theory and that according to the theory leads to 1 + 1 = 3.

This is obviously not good since the observations show that the theory is provably incorrect (or lets say incomplete), sso instead of discarding this still useful theory one has "invented" an extra term that explains why the calculations come to the "wrong" number and which covers the errors in the theory : DARK ENERGY/MATTER so then the theory becomes :

1 + 1 + "unobservable dark xxx" = 3

and everyone is happy.


We hard scientists, i.e. mathematicians, find this very funny. You might not understand the joke unless you are a mathematician.

We mathematicians also find the "heat distribution equation in one dimension" hilarious as well since an obvious consequence of it is instant communications faster than light as long as you can construct a thermometer accurate enough.


(of course we have our share of "issues" as well as Mr Goedel was so very kind to show us)

Re:That's a pretty bold statement... (0)

Anonymous Coward | more than 8 years ago | (#14489108)

You might as well claim it's all pasta sauce.

It's not cool when religion tries to inject unprovable concepts into the science classroom; I don't see why cosmologists are given so much more slack than the Bible-thumpers. They're both just making up random stories so they can sleep better at night.

Re:That's a pretty bold statement... (1)

Parelius (892100) | more than 8 years ago | (#14489121)

Amen to that!

Im starting to feel pretty despaired over the cludgework that Big Bang theory has become. Mysterious dark energy to explain the expansion of the universe, mysterious non-baryonic dark matter to explain the rotation curves of galaxies, and super-duper inflation speed of the earlier universe to explain the homogenity of the cosmic background radiation. This situation is screaming for a new beautiful theory to replace this mess and Im getting more and more convinced that may turn out to be plasma cosmology.

Also philosophically, this will be interesting as we've now become used to a universe with a beginning in time, and this creation is a very appealing/comfortable idea to us it seems. If plasma cosmology turns becomes the accepted theory, our universe no longer has a beginning in time, which is a bit of a challenging idea philosophically/religiously.

An extraordinary Claim requires... (4, Interesting)

helioquake (841463) | more than 8 years ago | (#14488869)

...extraordinary evidence to support it. I'm not an expert on this
topic (will hear more about it from local experts for sure), but
it doesn't sound a statistically significant claim to me.

For the life of me I can't recall a false study about something...
I think it's about pulsars / neutron star. Astronomers found the
first few pulsars and found them to be aligned in a similar
orientation. This provoked a few new thoughs and fresh ideas
among the community...but later only to realize that the first few
detections happened to be a freak series of coincidence; further
observations revealed that other pulsars orient in many different ways.

Choosing random samples is important here. I'm not sure how carefully
that thought process has been applied here by this author (i.g., that
is what Adam Rees alludes to, I think).

We have to be careful since some people tend to see what they want
to believe in.

Re:An extraordinary Claim requires... (1)

Joseph_V (908814) | more than 8 years ago | (#14488887)

If the researcher is asked about this specific topic he will admit that he does not have the evidence to support this claim conclusively... he was interviewed on the NPR early last week. But.. this researcher was smart enough to use an extraordinary claim to generate a huge media buzz, get some notariety for something that no one else will touch with a 10-foot pole, and ultimately generate some money for his research projects. Ahh politics...

He does not really believe in Dark Energy (4, Informative)

anandsr (148302) | more than 8 years ago | (#14488961)

He is merely collecting data to disprove the current gravitational model.
He actually believes in Dr. Mannheims Conformal Gravity. An attempt to define
gravity in terms of Conformal Symmetry, which the other three forces observe.

In the theory Dark Energy is just a manifestation of the repulsive component of
gravity. And this force changes with the evolution of the universe. He has just
found proof of this. This would mean that they have discovered something that has
not yet been predicted by the standard model. They have been hard at work to come
up with something that they can predict something that can be proved based on the
observation. The only other significant difference from the standard model is that
in the theory universe is always expanding, and there was no contraction phase.
The observations are not yet conclusive enough on this point.

more information (4, Informative)

anandsr (148302) | more than 8 years ago | (#14489009)

This is the actual press release from Dr. Schaefer.
http://www.phys.lsu.edu/GRBHD/pressrelease/ [lsu.edu]
It seems that the results are very damning to cosmological
constants.

Unfortunately there are no good web sites talking about
Mannheim's theory the only paper that explains a lot of
it is "Alternatives to Dark Matter and Dark Energy" which
can be accessed at http://arxiv.org/abs/astro-ph/0505266 [arxiv.org]

Don't Use Line Breaks (0, Offtopic)

ObsessiveMathsFreak (773371) | more than 8 years ago | (#14489049)

Please stop cutting off your
text lines with inserts. It
takes up vastly more space
than a paragraph with no line
breaks would. As you can see
this comment is taking up far
more horizontal space than it
normally would. If this get's
modded up, it will dominate a
substantial percentage of the
total area of this comments
page. That would be an abuse
of the Slashcode. In Future
please do not insert overly
many line breaks into your
comments. It's OK to seperate
paragraphs using line breaks,
but it's not OK to separate
sentences using them. OK?

Re:Don't Use Line Breaks (1)

SpaceAdmiral (869318) | more than 8 years ago | (#14489064)

Actually, I think that comment is using less horizontal space. You will rue the day you confused the words horizontal and vertical! Rue, I say!

Re:Don't Use Line Breaks (1)

ObsessiveMathsFreak (773371) | more than 8 years ago | (#14489081)

Actually is is using more horizontal space as well, due to the rectangular nature of Slashdot comments. But I do stand corrected, and my petty rebuttals are no real excuse.

Re: more information (2, Interesting)

Black Parrot (19622) | more than 8 years ago | (#14489297)

> This is the actual press release from Dr. Schaefer.
http://www.phys.lsu.edu/GRBHD/pressrelease/ [lsu.edu] It seems that the results are very damning to cosmological constants.


It seems that even if he's right it would only require one cosmological constant to be non-constant.

Or maybe not even that. Maybe the effect he's observing is dependent on something that changes with times, such as the temperature or density of the universe. Most cosmologists already believe the universe underwent a sort of "phase change" during the inflationary period, and it hasn't exactly destroyed the idea of cosmological constants.

Re:An extraordinary Claim requires... (0)

Anonymous Coward | more than 8 years ago | (#14489155)

I'm not an expert on this topic (will hear more about it from local experts for sure)

I'm not an expert on it either, but one of the first things they taught us in astrophysics class about dark energy is that there's no underlying explanation for it, no reason to think it would be constant in the future or past, and in fact, that inflationary theory mandates that it DID change in the past, or else we would still be inflating rapidly. So I think the article starts out a bit weak on the accuracy side when it says "Contrary to all expectations, the mysterious dark energy that is pushing the Universe apart may be changing with time." It changing is not counter to all expectations, but in fact, the expectation of it changing is part of the standard curriculum.

A stretch (1, Insightful)

Da3vid (926771) | more than 8 years ago | (#14488871)

I personally hate this whole dark energy thing. Its always this and that, here and there. It seems to me to be a poor attempt at a unified theory. Its trying to bring everything together into one thing and to account for all the oddities out there, but is this really any better than the Greeks accounting for oddities in terms of gods and goddesses? It seems to me that we are only adding increased complexity into an already complex system and we are not significantly increasing our understanding. What we are increasing is more unlikely system. Often, the most simple answer is the correct answer. I can't wait for the next new scientific revolution and the next paradigm shift. I'm bored of this one.

-Da3vid-

Re:A stretch (0)

Anonymous Coward | more than 8 years ago | (#14489020)

Why wait fer someone else to do the paradigm thing?
If yer bored, well... get TO it!
Otherwise quit quoting fresham, uh.. freshman texts.

Re:A stretch (how about this?) (0)

Anonymous Coward | more than 8 years ago | (#14489051)

Looking back

A lifetime ago, it was observed that the Universe is expanding. A few years ago, Scientists made another shocking discovery. The rate at which the Universe is expanding seems to be accelerating.

Since then, it's been speculated that something called "Dark Energy" is responsible for the apparent accelerating expansion; Einstein's "Cosmological Constant" (which he later called the biggest blunder of his career). It is supposed to make up 70% or more of everything in the cosmos, and IIRC, was supposed to have become the dominant force of nature a billion years or so before our solar system had formed. I suppose it could well be the case, but I am not so sure. I often wonder if perhaps the people involved have missed something obvious. (I am not a cosmologist, so obviously take what I am about to say with a grain of salt ;^).

My reasoning follows:

The farther we look into the cosmos, the further back in time we are seeing, as light travels at a finite speed (~300,000 kps). Our best instruments are showing us the Universe as it was half a billion years after the Big Bang, when the Universe was very much smaller, and everything was therfore closer together. I don't recall the exact estimated size, but lets say the Universe back then was 200 million light years across. Did it take light 200 million years to cross that distance? No. It took nearly 13,000 million years (13 billion), because of the Universes expansion.

At what speed does gravitational force propagate through the cosmos? Is it an instantaneous thing, or does it travel at a finite speed, as does light? If in fact the gravitational force travels at a finite speed, then masses at the edges of the Observable Universe would only now be exerting their (now greatly diminished) gravitational forces on each other. Additionally, if the rate of the Universes' acceleration is a constant (doesn't increase over time as with the Dark Energy scenario), then it would appear to us looking back, that the rate increased once the Universe got to a certain size, when it was just too big for the gravitational force to have had enough time to travel between them by that point in history.

I've made a few assumptions there, but until I see anything from a credible source showing my assumptions to be incorrect, I find my scenario to be more likely than "Dark Energy." It's an interesting Universe either way.

-------

The above is slightly modified from when I first posted it on November 17, 2005 @ 5:44 pm

http://cogscanthink.blogsome.com/2005/09/26/contra dictio-in-terminis/ [blogsome.com]

--Trent J. Townsend

Re:A stretch (how about this?) (0)

Anonymous Coward | more than 8 years ago | (#14489319)

Your main problem is that you're just speculating in the air without actually doing the relevant math to tell you whether your idea works or not.

When astronomers find evidence of dark energy, they measure a parameter called the deceleration parameter (q). It's called that because it's supposed to be positive if the universe is decelerating due to gravity, when we thought that was all to speak of. It can only be negative (according to Einstein's equations) if we have something in there that is either dark energy or a lot like it.

You can also determine the amount of dark energy from measuring the curvature of the universe (as the WMAP satellite has done via the cosmic microwave backgroud), and subtracting the portion which has to do with matter (baryons and dark) from other observations.

Either way, you find that you need something other than just matter. You need this dark energy stuff.

A push (1)

DigiShaman (671371) | more than 8 years ago | (#14489063)

I wrote on Slashdot about an idea of mine. I called it Proportional Displacement. Basically, the idea was that gravity is not a pull, but rather a push. Instead of matter warping space/time, it's actually trying to displace it and the space/time is actually trying to rush in a fill its own vacuum that matter is creating.

The current theory states gravity is like bowling ball on a sheet of rubber in that matter warps it. My idea is that the bowling ball is half-way exposed in this sheet of rubber along the equator and is trying displacing that bowling ball. But, it's not going anywhere. So, it's stretched around it PUSH the very matter that makes up the ball together.

I know it sounds wacky. But maybe with enough space between matter, it will start to push it all apart. If the matter is close enough, the space around the objects will be displaced toward each other. Think of it like a bell curve. Maybe...that's why galaxies can form, and yet they themselves are being pushed away form each other omni-directionally.

Re:A push (1)

DiamondGeezer (872237) | more than 8 years ago | (#14489516)

I'd mock but the moment has gone.

Gravity is not a force at all. That's where pretty much all amateur theorists fall down.

Re:A stretch (1)

Butterspoon (892614) | more than 8 years ago | (#14489126)

It's not *us* that keeps adding more complexity into the cosmological picture, it's the *universe*. All predictions previously had said that the expansion of the universe should be slowing down, whatever the fine details of the theory were. When it was discovered to be actually speeding up, cosmologists were stunned. No one really knows what dark enery is - the term is little more than a catch-all for "whatever is making the expansion of the universe speed up".

I think that in general terms, "paradigm shifts" in physics become harder and harder to achieve as time goes on, as there is more existing data that still has to fit with the new theory. Maybe we'll get lucky and a proper string theory or LQG will come along and explain everything, including dark energy, but don't hold your breath.

(Dark *matter*, on the other hand, is becoming better understood almost daily. There's little doubt now that it is real "stuff" that clumps together and so on.)

Re: A stretch (1)

Black Parrot (19622) | more than 8 years ago | (#14489273)

> I personally hate this whole dark energy thing. Its always this and that, here and there. It seems to me to be a poor attempt at a unified theory.

Perhaps you should write your favorite physicist or science journal about it. I'm sure they'd love to hear your views on it.

> is this really any better than the Greeks accounting for oddities in terms of gods and goddesses?

Yes, because even the most far-out cosmology doesn't invoke the unpredictable whims of powerful beings.

> It seems to me that we are only adding increased complexity into an already complex system

No, we're adding complexity to our description of a complex system, which is pretty much what we have to do when it turns out to be more conplex than our previous description could account for.

> Often, the most simple answer is the correct answer.

And often it's the wrong one.

Re:A stretch (0)

Anonymous Coward | more than 8 years ago | (#14489330)

Actually the dark energy is not as artificial as it may seem at the first sight. Quantum theory predicts and also observes spontaneous creation of particle pairs in vacuum and the process causing this seems to be the same one causing the "dark energy effects". At least that's what I've read... On the other hand the quantitative side does not match quite a bit - quantum theory predicts that the dark energy should be about 20 orders of magnitude weaker.

Stupid Scientists (0)

Anonymous Coward | more than 8 years ago | (#14488872)

"This is an intriguing result," admits Turner. But it certainly doesn't add up to a Nobel prize without further confirmation, he says. "I don't think it's a ticket to Sweden."

Are all scientist doing what they are doing for the Nobel Prize? No wonder the korean cloning fiasco happened.

Obligatory comment (-1, Redundant)

jurt1235 (834677) | more than 8 years ago | (#14488894)

Luke, come over to the dark side....

Re:Obligatory comment (1)

gbobeck (926553) | more than 8 years ago | (#14488902)

Clear your mind must be, if you are to discover the real villains behind this plot.

Re:Obligatory comment (0)

Anonymous Coward | more than 8 years ago | (#14489130)

Retard you are. Trolled and having had a nice day you will be.

Dark matter does not exist (-1, Flamebait)

Anonymous Coward | more than 8 years ago | (#14488898)

Dark matter is a pure invention.
It does not exist.
The reason the physicist talk about dark matter is because the measures are not coherent with today's physics.
Many scientists think that physics today is more and more a religion rather a science.
There exist works that can prove this but the papers are not accepted for publication because seen as heresy.

article wasn't very clear, but... (3, Insightful)

heatdeath (217147) | more than 8 years ago | (#14488917)

So...brighter means closer. Since that was the result that prompted us to think that the universe is expanding in the first place, I guess this means that the rate at which the universe is accelerating is accelerating.

http://en.wikipedia.org/wiki/Big_Rip [wikipedia.org]Big Rip.

clarification (1)

heatdeath (217147) | more than 8 years ago | (#14488983)

So...brighter means closer. Since that was the result that prompted us to think that the universe is expanding in the first place, I guess this means that the rate at which the universe is accelerating is accelerating.

I realized that I wasn't very clear when I said this - our current theory of dark energy came about because of a type Ia supernova explosion that was about half of the age of the universe. If the older xray sources are brighter than expected, then this means that the acceleration is accelerating. (If the xray sources had been *younger* and brighter, however, it would have meant that the acceleration was decelerating.

Not THAT again... (3, Interesting)

mcrbids (148650) | more than 8 years ago | (#14488918)

Re:Not THAT again... (3, Insightful)

helioquake (841463) | more than 8 years ago | (#14488934)

matter != energy.

Well, in this particular term that is.

I'm sure some nerds will bring in on Einstein reference that is E = mc^2.

Re:Not THAT again... (1)

SpaceAdmiral (869318) | more than 8 years ago | (#14488939)

Um, dark matter and dark energy are two different things. . .

As for me, I'm betting on the physicists who are working on tweaking the gravity equations for large distances. That has the potential to explain away a lot of wacky theories.

Energy destroyed or converted to matter? (1)

Mostly a lurker (634878) | more than 8 years ago | (#14488925)

If (big if) (1) the phenomenon we refer to as "dark energy" does turn out to be a single entity, and (2) (even bigger if) the strength of dark energy is decreasing over time, do we hypothesize that this is because the energy if being destroyed or because it is being converted into some other form that produces different observations?

At the end of the day, do we have enough data to be able to say anything about "dark energy" that is anything other than wild speculation?

Re:Energy destroyed or converted to matter? (0)

Anonymous Coward | more than 8 years ago | (#14489075)

is it wrong i instantly thought of the flying spaghetti monster and his noodly appendage the moment you said " does turn out to be a single entity " ?

young earthers - watch out! (0, Troll)

Robowally (649265) | more than 8 years ago | (#14488938)

Watch out because who knows, next they may tell you that the earth and universe are not 15000000 years old ......... but young!

But then, that would break the laws used by naturalists.

(i) We know the earth/universe is 15000000 years old because science says it is
(ii) Science is right!
(iii)Therefore the earth/universe is 15000000 years old! QED/p)

IANAP but... (4, Insightful)

Goalie_Ca (584234) | more than 8 years ago | (#14488981)

According to new research the strength of dark energy may be very different now than it was when the universe was young.

Maybe its just the engineer in me, but isn't it possible that we're just observing some other unknown effect. Something so complicated and exotic doesn't feel right. When it comes down to the math we juggle equations around, fit curves, and re-evaluate until the math yields a good approximation. Math juggling is one thing but I don't think there's a strong case for creating a physical entity for it.

Re:IANAP but... (1)

spectrumCoder (944322) | more than 8 years ago | (#14489017)

The fact is that scientists can't explain why the rate of expansion of the universe is decreasing without inventing a) a whole load of invisible matter (dark matter) or b) a new unknown force (but not gravity) that acts as an attractive force between mass.

They went by KISS and chose a). Can't blame them really, if you want a grand unified theory you don't want to go inventing new forces.

Re:IANAP but... (2, Interesting)

heatdeath (217147) | more than 8 years ago | (#14489027)

Maybe its just the engineer in me, but isn't it possible that we're just observing some other unknown effect.

MOND [wikipedia.org]

Re:IANAP but... (4, Informative)

anandsr (148302) | more than 8 years ago | (#14489101)

MOND cannot explain anything like this. It was designed to fit the galactic curves. It cannot do anything more. I wouldn't even place much faith in the theory designed around MOND, to come up with these results. Actually the result is alluding to Conformal Gravity by Dr. Mannheim. In this theory gravity has three components one like Newton, second that increases with distance and is felt at galactic distances, third that increases with the square of distance but is repulsive and is felt only at cosmological scales but does manifest itself as an extra attractive constant component at galactic scales.

In the theory repulsive component decays with the evolution of Gravity, and hence the Dark Energy which is what the repulsive component amounts to.

Re:IANAP but... (1)

Mr. Flibble (12943) | more than 8 years ago | (#14489034)

Maybe its just the engineer in me, but isn't it possible that we're just observing some other unknown effect. Something so complicated and exotic doesn't feel right. When it comes down to the math we juggle equations around, fit curves, and re-evaluate until the math yields a good approximation. Math juggling is one thing but I don't think there's a strong case for creating a physical entity for it.

Ha! Shows what you know! Clearly this is an interaction between the Phlogiston and Ether, not some engineers hypothisis! Clearly Maternal impression has had quite an effect on you, otherwise you would know enough about Vitalism to understand how the universe works!

Sheesh, some people.

---
(Note: The humor impared should check google)

Re:IANAP but... (1)

Decker-Mage (782424) | more than 8 years ago | (#14489059)

Hell, I'm qualified and have worked in over a dozen fields of engineering, including nuclear, here and I'm offended. When I'm not working on something else, I play with superstring theory for entertainment. There's something going on and I don't think that dark matter and dark energy are the solution. I think we are at a similar stage to where we were right after the Michelson-Morley experiment and/or the discovery of the photoelectric effect. Observations that don't make sense in the context of the current standard model so people are trying various fits/corrections to make it work.

I have my own pet theory about what is happening at the quantum level but I keep it to myself. It's so bizarre that even I don't believe it {shrug}.

Re:IANAP but... (0)

Anonymous Coward | more than 8 years ago | (#14489446)

Oh go on... Share! :D

String Theory Fallout (4, Interesting)

ObsessiveMathsFreak (773371) | more than 8 years ago | (#14488999)

There's already a few comments openly questioning and in some cases deriding the concept of dark energy. I think this could well be fallout from String Theory's current fall from grace.

It's looking more and more like String Theorists are on the wrong track. I think this may have bred a new skeptisism in people with regard to the more "out there" physics theories.

The whole debate about Intelligent Design may also be playing a part. There's been a very public question about "what is science". String Theory has already come under fire from this, and it's understandable that some other theories such as Dark Energy might also be brought under the spotlight of a new skeptisism.

This might be stifling for scientists, paticularly those with more outlandish sounding, but still reasonable hypotheses. But ultimately I think it will be good for science. No one should blindly accept any scientific theory without sufficient evidence. And supplying that evidence can only further validate the theory. In this sense, skeptics are good for science.

Re:String Theory Fallout (2, Insightful)

crotherm (160925) | more than 8 years ago | (#14489037)


Face it, we dont't what makes the universe expand/contract. We really don't know shite. All we can do is attempt to observe, and propose theories on those observations and try to falsify them. As we learn more, invent/discover better methods and devices for measurements, our understanding will evolve. I know this is basic stuff, but it seems many folks are forgetting this. We are mear children in our understanding of our universe.

Re: String Theory Fallout (1)

Black Parrot (19622) | more than 8 years ago | (#14489248)

> There's already a few comments openly questioning and in some cases deriding the concept of dark energy. I think this could well be fallout from String Theory's current fall from grace.

Fall from grace among scientists, or just among Slashdotters?

> The whole debate about Intelligent Design may also be playing a part. There's been a very public question about "what is science".

No, there have just been some high profile attempts to redefine science to include ID, never mind the fact that the new definitions import astrology as well.

We're Doooooomed! (0)

Anonymous Coward | more than 8 years ago | (#14489080)

Who can the greenies blame this one on then? James Lovelock says it's our fault for all the space pollution from our rockets. It's too late, there's no going back now. In another 200,000 million squillion years the human race is history.
The Universe is angry. Game over man! Game over!

Been there, seen that (2, Interesting)

Omega Blue (220968) | more than 8 years ago | (#14489083)

It wasn't that long ago - probably a year or two - that some researchers were claiming that c (speed of light) decreased since the Bang. I was quite skeptical at the time, because changing c is going to change the among of energy and matter in our universe.

Up till today I haven't seen another team confirming this.

Ob blackadder quote (4, Funny)

zmollusc (763634) | more than 8 years ago | (#14489095)

So, what you're telling me, Percy, is that something you have never seen is slightly less blue than something else you have never seen.

not exactly e=mc2 (1)

hapoo (607664) | more than 8 years ago | (#14489114)

almost all major physics theories / forumulas i've come across have been very simple and elegant. With current theories dark matter seems more of a fudge factor to account for what modern physics cant explain.

if you'd care to understand.... (2, Informative)

Anonymous Coward | more than 8 years ago | (#14489213)

...what the discussion is really about then for only a moment, pulleaze, ignore the "I hate this whole dark energy thing" or "dark matter didnt even EXIST right?" yadda... and, certainly, this all has little to do with string theory. remember this is observational cosmology, not physics.

it has been reasonably established from several independent observations (cosmic microwave background, supernovae 1a, large scale structure) that the expansion of the universe is accelerating; the universe today is expanding faster than it was in the past.

now, guess what? we *see* it, but dont understand how or why. we only know that all "matter" (baryonic and non-baryonic) attracts, therefore there must be some *repelling* force; out of ignorance, astronomers call this repellant "dark energy". *theorists go wild*

but this is not the point. the real criticism of this study is on the interpretation of the observations. in fact, understanding that requires little esoteric theory, it's quite simple. the essence is that Gamma Ray Bursts, observations of extremely powerful stellar explosions, are used to derive the geometry of the universe. this *can* be done, empirically, if one knows 1) how bright the explosions were intrinsically, and 2) if one knows their distances independently (i.e. through spectroscopy).

BUT... GRB physics is quite messy, so at this point nobody can claim *yet* to know what their intrinsic brightnesses are (such that they can be used as "standard candles"). second, measuring distances requires accurate spectroscopy which is *really* hard, and close to impossible for the most distant and faintest GRBs. third, the current sample of GRB observations with spectroscopy is small.

the main reason why the conclusions/interpretations as published in Nature are disputed is because of these difficulties.

astrosociology: claim what you can as early as you can. if you're right, you're the first and eternal glory is your part, if you're wrong, ppl will forget you anyway.

if you ask me, Nature's standards are slipping...

IANAP, but.... (1)

crhylove (205956) | more than 8 years ago | (#14489251)

I am not a physicist, but, it seems obvious to me that every action has an observable reaction in this universe, and that all things naturally observed are a cycle:

Therefore:

As the universe continues to expand, eventually Entropy will slow down measurably (perhaps not for many millenia, who can say how time works relevant to our current reality? We already know that it is not a constant, but relative.) This will have the effect rather catastrophically of altering everything in reality immediately, and triggering the eventual collapse of the universe, as the end result of the current cycle of expansion.

If the universe is as ordered and logical as we have thus far witnessed, it seems to be likely anyway.

rhY

Re:IANAP, but.... (0)

Anonymous Coward | more than 8 years ago | (#14489292)

*buzzzz*

maximum possible entropy rises more rapidly than entropy in an expanding universe. classical thermodynamics does not apply.

Dark Matter only one way to look at this issue (1)

bsavoie (946477) | more than 8 years ago | (#14489298)

Another way to see this problem is to consider the speed of light to be changing! This has been Charles Berner's observation in 1967, and I published it on my website 8 years ago. The key insight is that each of us creates the physical universe in order to manipulate others. As time passes, we are learning to trust others more. Therefore our quantum turn, the distance we can move while still interconnected is being extended. Therefore the speed of light is slowly increasing. The effect is geometric, since we all wait for the slowest among us. It is very simple really, if we are willing to wake up to our own true nature.
If you want to read more see http://www.dyad.org/d06twy1.htm [dyad.org]

dark energy linked to hubble constant (2, Interesting)

clockwork_orange (888652) | more than 8 years ago | (#14489320)

it was already suspected that dark matter and dark energy were different when the universe was young, they are both linked to the hubble constant H, which is different the further back in time you go. it might be new evidence i haven't read the paper in nature yet, but its not a new idea

Dark Matter/Dark Energy is a kludge (2, Insightful)

kcbrown (7426) | more than 8 years ago | (#14489465)

I don't know about you, but this whole dark matter/dark energy thing looks, sounds, and feels like a kludge to me.

It's almost as if the people who are proposing these explanations aren't willing to toss out the current explanations they have for things and essentially start from scratch. But when you start to kludge explanations together as they have with dark matter/energy, that's exactly what you should do: go back to the drawing board. Having to kludge something is a huge hint that you got something badly wrong somewhere way back towards the beginning.

Obviously whatever you come up with has to explain current observations to at least the degree that current conventional theories do, and current theories then have to become a "special case" of the more general theory, just as newtonian mechanics is a special case of relativity.

Re:Dark Matter/Dark Energy is a kludge (1)

kcbrown (7426) | more than 8 years ago | (#14489486)

As a followup, I should note that dark matter and dark energy are especially kludgy, and are in my mind essentially unscientific.

Why?

Because by definition they are something that cannot be observed. Instead, they are used to adjust the universe so that it continues to fit our explanations of it. I suspect that independent confirmation of the existence of dark matter/energy is impossible.

That said, of course there are some forms of "dark matter" which can and do exist: things like gas and dust. There's plenty of that in our own galaxy and a lot that we've observed in others, as well. But that's not what we're talking about here.

Anyway, when you start introducing invisible and unverifiable junk into your model of the universe in order to make it fit your theories, you're not doing science any more. In science, when you get a bunch of observations that don't fit your theories, you throw out the theories and start over (or, rather, you keep your theories as a special case unti you come up with something more universal).

Dark energy: undefined (0)

Anonymous Coward | more than 8 years ago | (#14489504)

Dark Energy Terror Alert: Orange
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