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Space Science

Dark Energy May Be Changing 346

Posted by ScuttleMonkey
from the arguements-over-hypothetical-science-ensue dept.
SpaceAdmiral writes "Nature is reporting that Dark energy, the hypothetical energy driving the universe's expansion, may not be as constant as previously thought. According to new research the strength of dark energy may be very different now than it was when the universe was young."
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Dark Energy May Be Changing

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  • by User 956 (568564) on Tuesday January 17, 2006 @04:25AM (#14488848) Homepage
    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.
  • Lets hope.. (Score:5, Funny)

    by Anonymous Coward on Tuesday January 17, 2006 @04:25AM (#14488852)
    ..that someone shreds some light on the matter.

    "I too, sense a disturbance in the Force"
  • Significant amounts of this so-called, "Dark Energy" have been measured around a certain Redmond, WA campus.
  • by tod_miller (792541) on Tuesday January 17, 2006 @04:27AM (#14488861) Journal
    It doesn't say if it gets stronger or weaker..

    wtf
  • by numLocked (801188) on Tuesday January 17, 2006 @04:30AM (#14488868) Homepage Journal
    ...considering no one even knows if dark energy EXISTS.
    • 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.
      • 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 exis
    • When physicists brew up this stuff it is "fancy curve fitting". Over time the underlaying mechanism and "dark matter" will either be confirmed with a tighter theory and set of more elegant math or end up in the dustbin of "what were we thinking?" ideas.
  • by helioquake (841463) * on Tuesday January 17, 2006 @04:30AM (#14488869) Journal
    ...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.
    • by anandsr (148302) on Tuesday January 17, 2006 @05:02AM (#14488961) Homepage
      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.
  • A stretch (Score:2, Insightful)

    by Da3vid (926771)
    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
    • Somebody's been reading Kuhn in an introductory english class. =P
    • 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 eq
    • > 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
      • 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.

        Of course, often it also turns out that the complexity of the description isn't due to the complexity of the system, but due to the description not fitting the system well. The classical example for that are the epicycles. All that complexity vanished as soon as Kepler found his three laws. Now, of course looking clos

  • by heatdeath (217147) on Tuesday January 17, 2006 @04:47AM (#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.
    • 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 accelerat
  • Not THAT again... (Score:4, Interesting)

    by mcrbids (148650) on Tuesday January 17, 2006 @04:47AM (#14488918) Journal
  • Ebony Energy, you Insensitive Clod!
  • 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?

  • IANAP but... (Score:5, Insightful)

    by Goalie_Ca (584234) on Tuesday January 17, 2006 @05:10AM (#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... (Score:3, Interesting)

      by heatdeath (217147)
      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... (Score:5, Informative)

        by anandsr (148302) on Tuesday January 17, 2006 @05:59AM (#14489101) Homepage
        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.
        • The last sentence should read
          In the theory the repulsive component increases with the increase of the size of the universe, and hence the dark energy should increase with time.
    • 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 h
    • 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 cur
  • 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.

    • 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.

    • > 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 defini
    • "In this sense, skeptics are good for science."

      Ummm, science is formalised skepticism.
    • The history of science is littered with ideas and theories that at the time were ad hoc or kludge factors. Planck himself was unimpressed with his quantization hypothesis and so were many of his contemporaries. It was Einstein who took it seriously and applied it to phenomena. Then afterwards Bohr applied it to his atomic model. Eventually in 1918 Bohr was given a Nobel Prize for his discovery 18 years earlier. Yet at this time quantum theory was still not fully developed. There was no actual theory in plac
    • Can you elaborate on why dark energy changing would suddenly change string theory? My understanding of string theory is in depth, but I am by no means an expert. I can't think of any reasons of how dark energy expansion rate or any other would interupt anything to do with super string or m theory.

      In fact, to keep it simple, I'd say that some of these findings actually support the membrane theory. Additionally, part of the string theory equations that actually hold water support dark matter and dark ene

  • by Omega Blue (220968)
    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.
  • by zmollusc (763634) on Tuesday January 17, 2006 @05:57AM (#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.
  • by Rogerborg (306625) on Tuesday January 17, 2006 @06:26AM (#14489145) Homepage
    Now do you see the folly of driving huge SUVs?
  • by Anonymous Coward
    ...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
  • Maybe the Xeelee are winning their billion-year war against the dark matter photino birds [wikipedia.org]?
  • 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
  • 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 somethin

    • A British astrophysicist says apparent acceleration of universal expansion can be explained by add a slight elliptical warp to the geometry of space. Then too, some physicists like Einstein claim warps and accelerations are physcial equivalents. The presence of alternative matter and energy could be causing the warp.

      (This astrophysicist keynoted the 2004 SIGGRAPH because his mathematics is widely used in computer graphics.)
  • That is why it is hypothetical.

    "Could Einstein's theory of gravity, which has proved to be correct in all cases so far, be somehow wrong?"
    (from http://chandra.harvard.edu/xray_astro/dark_matter 2 .html [harvard.edu])
    Sure, it could be wrong...something as theoretical can always be wrong. I think the observations that man can make from Earth most likely are bent or distorted by the massive size of the galaxy and the distances between them. Something so huge is hard to measure or calculate definitively.
  • In Soviet Russia dark matter changes YOU!
  • by Mulletproof (513805) on Tuesday January 17, 2006 @09:21AM (#14489710) Homepage Journal
    "Dark Energy May Be Changing"

    Speak for yourself. I'm keeping my talent points at 31/00/21 for nightfall and shadow burn.

    ...Eh, nevermind. You would have had to have been there.

  • by Wormholio (729552) on Tuesday January 17, 2006 @09:32AM (#14489748)
    A longer article on this in the NY Times [nytimes.com] says that other astronomers doubt this result.
  • by ozbird (127571) on Tuesday January 17, 2006 @09:39AM (#14489792)
    "There is a theory which states that if ever anybody discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

    There is another theory which states that this has already happened."
  • Slashdot: Science for nerds, like dark energy and matter.
  • So something that is invisible, cannot be directly measured now has to undergo constant changing properties so that it fits theory. The other theories I've heard of that had such problems were heliocentricity, phlogiston and aether.

    Occam is rolling in his grave.

    • So something that is invisible, cannot be directly measured now has to undergo constant changing properties so that it fits theory...

      Good. You're beginning to understand how science in the real world works.
      And people make fun of creationism and intelligent design.
      • You're beginning to understand how science in the real world works

        I am a scientist. I understand how science works in both the real world and in theory. This is an example of science not working. Creationism and its weasel word alternative name Intelligent Design are not connected to science in any way; they are politics and religion.

  • first we don't have it, then we have it, then we don't have it, then we have it again....
  • Why shouldn't dark energy change? gain and lose power (though i would think lose power)...as it travels, in its wake it leaves dust clouds, atoms, rocks, etc...new things are formed - so where do these new things come from? There has to be something supplying these resources - and if it is coming from this dark energy - shouldn't that be depleting it?

    Just my two cents...I guess that I am of the mindset that you can't get something from nothing?
  • A marine I once knew introduced me to the term "Kludge" [reference.com] (he pronounced it KLOOJ). It is a hastily-assembled, inelegant fix to an otherwise fragile construct.

    I love physics, but beware any time a physicist says "I've found something that changes/that I can change to fit in my otherwise not-completely-working theories."

    This isn't to say it's not true. The universe is peculiar. But beware.

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