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9 Billion-Year-Old "Dark Energy" Reported 118

Posted by Zonk from the leaving-it-there-for-safekeeping dept.
loid_void writes to mention a New York Times article about the discovery that dark energy, or antigravity, was present at the formation of the universe. A team of 'dark energy prospectors' at the Space Telescope Science Institute theorizes that this may have directed the evolution of the cosmos. By observing supernova activity almost 8 billion years in the past, the team was able to study whether or not dark energy has changed over the millennia. From the article: "The data suggest that, in fact, dark energy has changed little, if at all, over the course of cosmic history. Though hardly conclusive, that finding lends more support to what has become the conventional theory, that the source of cosmic antigravity is the cosmological constant, a sort of fudge factor that Einstein inserted into his cosmological equations in 1917 to represent a cosmic repulsion embedded in space. Although Einstein later abandoned the cosmological constant, calling it a blunder, it would not go away. It is the one theorized form of dark energy that does not change with time. Sean Carroll, a cosmologist at the California Institute of Technology who was not on the team, said: 'Had they found the evolution was not constant, that would have been an incredibly earthshaking discovery. They looked where no one had been able to look before.'"
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9 Billion-Year-Old "Dark Energy" Reported More

9 Billion-Year-Old "Dark Energy" Reported

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  • More from Sean Carroll (Score:5, Informative)

    by joebebel ( 923241 ) on Saturday November 18, 2006 @05:31AM (#16894796)
    Sean Carroll (and some other notable physicists) have a blog which covered this in more detail. See http://cosmicvariance.com/2006/11/16/dark-energy-h as-long-been-dark-energy-like/ [cosmicvariance.com]

    He provides a great explanation for the reader without familiarity with advanced physics, but at a level which is still interesting to the technical reader.
    • A while ago I was reading a similar post on slashdot about dark matter, energy etc. One gentleman calld it all bs and pointed out a link to a website http://www.holoscience.com/news.php?article=knb8hx 39&keywords=darkenergy#dest [holoscience.com] which I decided to follow for the heck of it that basically had conventional eletromagnetic explanations for absolutely every mystery in astrophyics. Apparently the whole dark energy fiasco in astrophysics arises only because astronomers don't study the physics surrounding plasm

      • Re: (Score:1)

        by arminw ( 717974 )
        ....Apparently the whole dark energy fiasco in astrophysics arises only because astronomers don't study the physics surrounding plasma and electricity enough.......

        It's more likely that the cosmologists make some basic assumptions to fit the preconceived evolutionary philosophy of immense periods of time for all cosmological processes. Another assumptions made is that gravity was and is the dominant force controlling the formation and operation of the universe on the large scale as well as it small beginni

        • Re: (Score:3, Insightful)

          by gilroy ( 155262 )
          Blockquoth the poster:

          If a theory or whole body of theories has to resort to phenomena and processes that cannot be observed today, then perhaps it is time to examine the assumptions that make it necessary to resort to nebulous constructs, such as dark matter and energ

          I totally agree! And while we're at it, what's the deal with these so-called "a-toms"? Have you ever seen an atom? No! No one has. Atoms are just hypothetical constructs invented to maintain the dominance of the currently-funded paradigm,

        • Theories that allow these "constants" to vary and postulating that gravity is NOT the dominant force, especially in the beginning, will make for a lot simpler, more elegant explanations of current observations.

          But the point is not to explain what we see in the sky now. The point is to be able to make testable predictions about what we will see in the sky when we have the means to look in new ways with new telescope technology and deployments at some time in the future.

          The problem with many alternative theo

  • This history is getting twisted (Score:5, Interesting)

    by jarek ( 2469 ) on Saturday November 18, 2006 @06:41AM (#16894978)
    When Einsteins introduced the general theory of relativity, the universe was believed to be static. Hence, Einstein introduced a constant to make it so. The expansion of space is inherent to the original formulation. Later when Hubble presented his findings that the universe was in fact not static, Einstein realized that he made, what he called, the blunder of his life.

    • Re:This history is getting twisted (Score:4, Informative)

      by jpflip ( 670957 ) on Saturday November 18, 2006 @11:29AM (#16896124)
      That's true, and thanks for reminding us of it - too many people get the erroneous idea that Einstein predicted all of this 90 years ago.

      Nonetheless, Einstein's cosmological constant is not just a fudge factor he introduced. The equations of general relativity are the most general equations you can write down consistent with certain principles (the equivalence of gravitational and inertial mass, among others). The main terms relate the curvature of space to the local matter/energy distribution, but there is one more term which is consistent with the principles and should be included - the cosmological constant. The constant may be zero, of course, but a priori it's something you need to understand. Einstein chose a particular value of the constant to produce a static universe - a blunder, since he could have realized that almost any value of the constant gives an expanding or contracting universe.
  • Just trying to wildly "think outside the box" here: suppose that gravity is conserved - for every quantity of gravity that is exerted by matter, an equal quantity of antigravity is left behind in the "ether".

    The antigravity drives the expansion of the universe, and the gravity drives the accretion of matter into stars and planets. The "big bang" then was some kind of probabalistic quantum event that separated out some gravity and antigravity.

    This is not science, I know. But sooner or latter all of these com
    • Similar to Einstein saying "God doesn't play dice", then quantum uncertainty taking off. It's possible that quantum mechanics is the basic set of rules and particles behind the universe, but I doubt it. Who's to say what we know now is as good as it gets?

      Even more outside the box, is antimatter affected by gravity? If you throw a positron (the antiparticle of an electron) into an electric field it will behave oppositely to an electron. Logically, if you throw any particle with antimatter into a gravitationa
      • Antimatter != dark matter ?
      • Even more outside the box, is antimatter affected by gravity? If you throw a positron (the antiparticle of an electron) into an electric field it will behave oppositely to an electron. Logically, if you throw any particle with antimatter into a gravitational field it will behave oppositely to conventional matter.

        Somehow I have my doubts about that because that would imply a negative mass too would it not? Given this assumption though, then there is only one speed that antimatter would be traveling at, 100%

        • Re: (Score:1)

          by Dabido ( 802599 )
          '...then there is only one speed that antimatter would be traveling at, 100% of C speed.'

          How about greater than C and it's travelling backwards through time?

    • Re: (Score:1)

      by Anonymous Coward
      You're just making things up on the spot. And here I was thinking the string theory is too speculative.

      I love it when people who are not physicists try to think "wildly outside the box" ...about physics.

      • Re:Suppose that gravity is conserved (Score:5, Interesting)

        by Dunbal ( 464142 ) on Saturday November 18, 2006 @09:08AM (#16895460)
        I love it when people who are not physicists try to think "wildly outside the box" ...about physics.

              Or anyone who tries to speculate about anything that is not their field. Human knowledge has become specialized for a reason. Anyone who has completed a university degree at the doctorate or masters level knows exactly how much detail you have to learn about something to really understand it. This doesn't apply to only physics. As a physician I know more about human bodies than most people - despite the fact they've lived their entire lives in one.

              Still I cannot fault the GP - such "speculation" is what drives the whole scientific process anyway. It's the first step. If only everyone would back up their pet hypothesis with experimentation we'd advance our knowledge even faster!

        • Re: (Score:1)

          by GnuDiff ( 705847 )
          Oh yes, I know the feeling :)

          Only the other way round - I love it when physicists, computer guys and basically anybody with a bit of spare time, think that because they are recognized specialists in their field, they can authoritatively speak about philosophy, arts, literature, etc.

          • Re: (Score:2)

            by finity ( 535067 )
            What? Arts require creativity and thinking. If you're a recognized specialist in any scientific field, you probably have some ability to think, and think creatively. Also, you might just have time and money to take in some of the arts, or think philosophically. Maybe I read your post wrong, but there is a reason why many people (like Newton) are recognized for their unique philosophy as well as their contribution to the sciences.

            On the other hand, it is pretty annoying when someone thinks they know ev
          • "I love it when physicists, computer guys..."

            I love it when art snobs think their opinion matterrs.

        • Re: (Score:2)

          by metlin ( 258108 )
          Still I cannot fault the GP - such "speculation" is what drives the whole scientific process anyway. It's the first step. If only everyone would back up their pet hypothesis with experimentation we'd advance our knowledge even faster!

          Exactly. Not to mention the number of IANAL posts that abound on Slashdot on any law-related topic.
          • Except that it is actually quite important for the general public to understand the laws. Physics and friends, while much more interesting IMHO, are not required, for the good functioning of our country (or any halfway democracy), to be understood by the lay public.

        • Re: (Score:2)

          by abigor ( 540274 )
          This is particularly true for evolution, where all kinds of "common sense" types come out of the woodwork. They read somewhere that evolution = animals magically splitting into new species, plus they are often religious anyway, so off they go to argue about something they know nothing about. I guess it's because the overall gist of evolutionary theory can be communicated in layman's terms. so they somehow feel they are qualified to debate its fundamentals.
      • You forget Einstein was a Patent Office Examiner in Switzerland in 1905 when he published four papers that revolutionized physics. One of those articles won him a Nobel prize. When he wrote those articles he was not yet a physicist; he only held a teaching diploma and had been unable to find a teaching post. He received his doctorate in 1905 at which point he was a physicist. Here's a quote from wiki about his breakthrough articles:

        During 1905, in his spare time, he wrote four articles that participate

    • Re: (Score:2, Insightful)

      by Anonymous Coward
      Your theory is pretty much pointless without hard physics/math to back it up.

  • Dark Energy... only if it was a big bang (Score:5, Interesting)

    by Anonymous Coward on Saturday November 18, 2006 @08:32AM (#16895344)
    Honestly, there are real alternatives to the big bang theory. One of them is the idea that our "universe" is at the center of a black hole, which effectively places the same limits (you can't get out, and neither can light) on the boundary.

    If that's the case, the "big bang" turns into the initial collapse; and the "dark energy" that drives expansion becomes the space-energy expansion inside the schwarzschild radius that is needed for conservation of energy.

    I have a relative who is working on some of this...

    http://absimage.aps.org/image/MWS_SES06-2006-00005 4.pdf [aps.org]
    http://physics.fau.edu/Events/Gulf_Coast_2006/Talk s/Rudmin/POSTER0H.PDF [fau.edu]

    • Re:Dark Energy... only if it was a big bang (Score:5, Interesting)

      by Decaff ( 42676 ) on Saturday November 18, 2006 @10:04AM (#16895682)
      Honestly, there are real alternatives to the big bang theory. One of them is the idea that our "universe" is at the center of a black hole, which effectively places the same limits (you can't get out, and neither can light) on the boundary.

      If that's the case, the "big bang" turns into the initial collapse; and the "dark energy" that drives expansion becomes the space-energy expansion inside the schwarzschild radius that is needed for conservation of energy.

      This needs a lot more explanation. There is no expansion at the centre of a black hole, only an inevitable collapse. A black hole analogy make have made some kind of sense if the universe was closed, but it isn't - it is not only open, but accelerating. If anything, the accelerating universe is more like a white hole (where separation becomes inevitable) than a black hole. There are other types of model that approximate the universe, like gravastars, but surely not black holes.

      • If that's the case, the "big bang" turns into the initial collapse; and the "dark energy" that drives expansion becomes the space-energy expansion inside the schwarzschild radius that is needed for conservation of energy

        "This needs a lot more explanation. There is no expansion at the centre of a black hole, only an inevitable collapse .."

        There is a collapse only the timeline is reversed so we see the universe expanding .. :)

        Re:Dark Energy... only if it was a big bang (Score:5, Interesting)

        • Re: (Score:2)

          by Decaff ( 42676 )
          There is a collapse only the timeline is reversed so we see the universe expanding .. :)

          That is why I said it was more like a white hole.

          Also, it just doesn't work to reverse things. For example, if you reverse the timeline of the expansion of the universe you would get a decelerating collapse. Inside a black hole there is an accelerating collapse.

          • Re: (Score:2)

            by rs232 ( 849320 )
            "Also, it just doesn't work to reverse things. For example, if you reverse the timeline of the expansion of the universe you would get a decelerating collapse. Inside a black hole there is an accelerating collapse"

            The universe is in a state of accelerating collapse. The timeline is reversed. That's why you see it expanding.
            • The universe is in a state of accelerating collapse. The timeline is reversed. That's why you see it expanding.

              In our timeline we see the universe in a state of accelerating expansion. If you reverse that, you get decelerating collapse.

              No amount of timeline flipping will produce a state of accelerating collapse.

              The reverse of accelerating collapse is decelerating expansion. But we don't see that - supernova data at the end of the last decade revealed we see accelerating expansion.
    • Bing bang theory is the equivalent of the theory that is saying that earth is flat and that earth or sun is the center of the Universe. At the beginning is the wrong assumption that time is liner and unidirectional. Alexander Franklin Mayer thinks this is not true and I full agree. Some very exciting stuff can be found here: http://www.afmayer.net/ [afmayer.net]. Basically Universe is eternal, doesn't have beginning nor have end as a whole because time has no beginning or end. Universe is finite but unbounded.

    • Re: (Score:1)

      by cbacba ( 944071 )
      If the current matter density estimates are accurate, then at the current value of around the equivalent of 6 hydrogen atoms per cubic meter, then there should be a schwarzchild radius of around 14 billion light yrs - a mere coincidence with the current notion of our universe's size?

      One should wonder if when we look at possible black hole whether or not any of our understood laws of physics work inside its schwartzchild radius - assuming it has one (isn't spinning). Now one perhaps should wonder if our uni

      • Re: (Score:2)

        by Decaff ( 42676 )
        If the current matter density estimates are accurate, then at the current value of around the equivalent of 6 hydrogen atoms per cubic meter, then there should be a schwarzchild radius of around 14 billion light yrs - a mere coincidence with the current notion of our universe's size?

        But that isn't our universe's size. The oldest light we can see is close to 14 billion years old, but the universe has been expanding while that light has been travelling, and the light gets carried along with it - the 14 billi

  • Anyone here care to try to poke holes in this? (Score:4, Interesting)

    by Pictish Prince ( 988570 ) <wenzbauer@gmail.com> on Saturday November 18, 2006 @09:19AM (#16895500) Journal

    Dark energy doesn't exist. Rather, the strong equivalence principle [wikipedia.org] is exactly correct: Matter creates space-time and gravitational effects are due to space being created by a massive body, making a reference frame at rest with respect to the massive body an accelerated frame.

    This obviates the need for "dark energy". If matter creates space then of course the universe will expand. No need for a fudge factor. I have read through James Lawler's "photonic theory of matter" [owt.com] several times and I can't find much wrong with it.

    • I'm no astrophysicist and no formal education on the subject, but from what I understand (from reading Stephen Hawking's books and various other sources) is matter and energy can simply be created at the expense of creating more gravity.

      But if that were the case why isn't the universe collapsing due to the fact matter naturally collects and eventually forms black holes.

      Even with the fact that matter creates space-time and gravitational effects, why doesn't matter simply attract all other matter in the univ

      • Re: (Score:3, Informative)

        by Decaff ( 42676 )
        Even with the fact that matter creates space-time and gravitational effects, why doesn't matter simply attract all other matter in the universe?

        It does.

        Actually, I think I just agreed with you except if that were the case then that would mean the universe isn't actually expanding, but rather the observations we are getting from other galaxies is itself changing because of increased gravity we get the shift in the spectrum by getting less and less of that energy from other galaxy.

        This is a sensible suggestio

    • Re: (Score:2, Insightful)

      by Anonymous Coward
      Dark energy doesn't exist. Rather, the strong equivalence principle is exactly correct:

      Dark energy does not violate the strong equivalence principle.

      Matter creates space-time and gravitational effects are due to space being created by a massive body

      That's not what the strong equivalence principle says. Read your own link.

      making a reference frame at rest with respect to the massive body an accelerated frame

      That exists in ordinary general relativity: you have to accelerate to hover at rest above a gravitati

    • Re: (Score:2)

      by jpflip ( 670957 )
      First off, the problem dark energy tries to solve isn't the expansion of the universe, it's the acceleration of that expansion over time. This is not something the Lawler piece tries to address, so it's not relevant to this discussion.

      In general, the Lawler piece looks like an exercise in numerology and formula hunting. In chapter 2, for example, he appears to use his composite photon model to explain the spectral lines of halogens, and suggests that this relationship is startling. But this is just the 1
      • I should have linked only to the section on gravity. My point is that according to the SEP space must be created somewhere beneath us to account for the acceleration. I should have added also that this only applies in a flat space universe (maybe like the gauge space of Hestenes [wikipedia.org])

    • Coiled space/time (Score:1, Funny)

      by Anonymous Coward
      I thought matter was coiled space / time bound by some form of energy... Isn't it?
    • Yay! Yet another crackpot GUT on /.! Congratulations.

      Considering that GUT is at least PhD level material, I would suggest that no GUT be taken seriously until it has been peer reviewed by experts - something that does not appear to apply to Dr. James H. L. Lawler's theory (what you linked).

      I did some searching on this name and found a variety of things, something about "electrical rockets," and a website purporting to show his "Professor Dr.James H.L.Lawler's revolutionary oil recovery method designed
  • A constant vacuum energy of about -1 probably rules out some of the wilder ideas about the future of the universe, like the Big Rip [aip.org], in which the end of the universe could be only a few tens of billions of years away.

    So this is kind of good news....

  • A strange thing happened to the universe five billion years ago. As if God had turned on an antigravity machine, the expansion of the cosmos speeded up, and galaxies began moving away from one another at an ever faster pace.

    Matter is denser energy. And energy is denser information.

    NASA scientists estimate that 23% of matter is dark, and 73% of that dark matter is dark energy. Likewise, the majority of that dark energy is dark info.

    Dark info is all that would have transpired in our universe once it ends/rebe

  • Quote from article (Score:2, Interesting)

    by theskipper ( 461997 )
    "Dark energy makes us nervous."

    This topic has been worn out on /. before but this quote is a good example of what's been discussed. Does it bother anyone else when a scientist makes a statement like this to a layman audience (i.e. majority of NYT's readership)?

    It makes it seem like refinement or going back to the drawing board is a bad thing. As opposed to what it really is, a step forward to discovering the correct basis of how the universe works through the scientific method. Using words like "nervous"

    • Re: (Score:1)

      by Tablizer ( 95088 )
      Using words like "nervous" implies a thought process where science is equivalent to religion based on unwavering doctrine.

      "Nervous" is a scientists way to saying that something odd is happening in which they don't have enough information or have a big hole in a model. It does not mean they won't look into it. It is just a human way of expressing the encounter of a rough spot.
                 
    • "This topic has been worn out on /. before but this quote is a good example of what's been discussed. Does it bother anyone else when a scientist makes a statement like this to a layman audience (i.e. majority of NYT's readership)?"

      Does it bother anyone else when "scientists" engage in rational metaphysics and invent new forces/particles, that can not be observed or directly measured, in order to explain some theory. Does this invention of forces/particles not strike others as being unscientific.
  • Can someone tell me when I get my anti-grav car?

    • Can someone tell me when I get my anti-grav car?

      When you build it. The info is out there, if you can find it, and tell it apart from the hoaxes.
      The energy cartels of the world are not going to let anyone put anti-grav cars into production, at least not in the first half of this century, by my guess. Have you noticed how hard it is just to start production of an electric car, no matter which country you try in, even though the first electric car was built over 150 years ago?

      Alternatively, you could ask the U

  • I sneeze on your theory .. (Score:3, Funny)

    by rs232 ( 849320 ) on Saturday November 18, 2006 @01:51PM (#16897182)
    "the Jatravartid people of Viltvodle VI believe that the entire Universe was in fact sneezed [wikipedia.org] out of the nose of a being called the Great Green Arkleseizure"

    If you're so clever answer this then. If a dropped cat always lands on its feet and dropped toast always lands butter side down, what happens if you strap a slab of toast butterside up, to the back of a cat and drop it out a window.
    • ahh, but the mythbusters have already proven that buttered toast does not, in fact, always land buttered side down.
    • Well, some would say that some form of singularity would form from the contradicting factors. However, I believe the cat will just get bored from being dropped out of a window and occasionally getting toast smeared on it, and decide to walk off.

      (A test for mods to see if they can find humor in a more-than-usual obscure, yet obvious reference...)

    • Re:I sneeze on your theory .. (Score:4, Funny)

      by Dausha ( 546002 ) on Saturday November 18, 2006 @08:43PM (#16900700) Homepage
      "If you're so clever answer this then. If a dropped cat always lands on its feet and dropped toast always lands butter side down, what happens if you strap a slab of toast butterside up, to the back of a cat and drop it out a window."

      I'm sorry, but you're intruding on my patent. See, I patented this technology several years ago as a means of contragravity. But you've made a serious mistake in your description. Quite simply, the cat/spread begins to spin and hovers. The distance above the surface at which the invention hovers is based on a complex formula, but contains four variables: species and age of the cat, the type of spread, and the quality of the material below the invention.

      That is, if you use butter and drop an adolescent tabby cat out the window, the cat invariably will land on its feet. This is because the spread/material quotient is non-optimized. If instead you drop the same tabby cat over an expensive, light-colored, Persian carpet and the spread is grape jam, then the cat will typically hover about 16.1415 cm above the surface. Naturally, other species of cats will vary the height, as will the age of the cat--so left to its own devices, the older cat will cause the balance to tip in favor of the spread and the carpet will be stained. (This was important when responding to a USPTO office action as they initially thought the invention might be a perpetual motion devices, and therefore, unpatentable.) Conversely, a kitten would spin so fast as to create instability in the system or even cause poor kitty to fly apart from the force.

      My company's current project is to manufacture an enclosure that allows the cat to be used to create lift. The goal is to create a vehicle useful for local commutes. It operates similarly to the Wankel rotary engine, in that the walls are all lined with the same quality carpet (to maintain stability) and the spread is added as needed from an intake port. A slightly opened area on the bottom allows the force of the cat's rotation to generate lift (the exhaust port) on the appropriate surface. We believe if roadways were repaved with green outdoor carpeting, then we can solve reliance on petroleum-based fuels. Propulsion is generated by having two pairs of these devices that rotate as needed to push the vehicle forward.

      Naturally, the cats will need to be changed out every few days due to nausea, dehydration and hunger. We also recommend that cats be replaced every six months for optimum performance.

      Hey, if dark energy is possible, then so is the catatronic (tm) drive.
    • then it will be in a quantum state that is 50% up and 50% down. That was easy, though I guess we need a Schroedinger's pot of butter too.
  • It's funny when people say things like "the source of cosmic antigravity is the cosmological constant". It's like saying that airplanes are kept aloft by bernoulli's equations.

    No, equations and models do not give rise to physical effects. They attempt to describe the observed effect.

    • Re: (Score:2)

      by Dausha ( 546002 )
      "[E]quations and models do not give rise to physical effects. They attempt to describe the observed effect."

      So, the assumption is what we're observing is correct, and so the equations and models are correct. That's what is great about assumptions---they can be completely wrong and still justify the outcome. I believe this falls into a circular reasoning fallacy. We observe X and use formulas to prove that X is true.

      So, if we're all color-blind, then our observations would be totally off---but at least the m
  • Very bad article from the NY Times.
  • Will the scientists exploring this metal become the first team of costumed superheroes, evolving themselves due to the cosmic radiation.

    Am I the only one who giggles at the prospect of "radiation allowing you to stretch your cells". I still think Dr. Fantastic (PHD) should just call himself "Tumor Man" and let all speculative debate about his powers lie to rest.
  • The existence of neither dark energy nor dark matter have been materially proven, yet already "scientists" are treating them as gospel and trying hang yet more theories off the presumption that they exist. There's a word to describe such mentality: religion. Physicists and cosmologists hellbent on identifying a Unifying Theory of the Universe would be wise to take a dozen steps back and reflect: a Unifying Theory sounds an awful lot like a monotheistic god. Jehovah/Allah is the original "unifying theory"
  • loid_void says "It is the one theorized form of dark energy that does not change with time." There are some now who accept the "constant" but who think that it is a variable, yielding various results concerning the expansion of the universe.
  • the discovery that dark energy, or antigravity, was present at the formation of the universe. "...[T]he source of cosmic antigravity is the cosmological constant, a sort of fudge factor that Einstein inserted into his cosmological equations in 1917 to represent a cosmic repulsion embedded in space."

    Revised: Nature has a love-hate relationship with vaccum.

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