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Fermilab Reports Dark Energy Not Needed

An anonymous reader writes "A Fermilab press release reports that the expansion of the universe may be explainable without the need for dark energy or a cosmological constant. Apparently, ripples from inflation in the early universe may account for the observed expansion rate of the universe."

9 of 416 comments (clear)

  1. How did the ripples get there? by Dancin_Santa · · Score: 5, Insightful

    If there was nothing to push against, what would cause something to be held back and "ripple" as if there were some sort of repulsive force?

    Let's say we've reached the edge of the universe, what happens when we step beyond that boundary? What is out there that would possibly hold back further expansion of our universe?

  2. Re:But what about the Horizon problem? by PureFiction · · Score: 5, Insightful
    If you read the article you would see they address this issue. The key is to realize that the horizon extends beyond what we can see (our cosmic horizon):
    • It is widely believed that during the inflationary expansion early in the history of the universe, very tiny ripples in spacetime were generated, as predicted by Einstein's theory of General Relativity. These ripples were stretched by the expansion of the universe and extend today far beyond our cosmic horizon, that is over a region much bigger than the observable universe, a distance of about 15 billion light years. In their current paper, the authors propose that it is the evolution of these cosmic ripples that increases the observed expansion of the universe and accounts for its acceleration.


    • "We realized that you simply need to add this new key ingredient, the ripples of spacetime generated during the epoch of inflation, to Einstein's General Relativity to explain why the universe is accelerating today," Riotto says. "It seems that the solution to the puzzle of acceleration involves the universe beyond our cosmic horizon. No mysterious dark energy is required."
  3. Comment removed by account_deleted · · Score: 4, Insightful

    Comment removed based on user account deletion

  4. Re:Not Funny, Insightful by wanerious · · Score: 5, Insightful
    Insightful? What would you like to have happen? Publish fewer articles? Not research it so much? Sheesh.

    This anti-intellectualism stain in /. responders is saddening. Basically it seems to be, "I don't understand what they're talking about, so I think I'll make fun of them" or "I don't understand the thousands of papers that have been published, so I'm going to shout something superior-sounding from the cheap seats". Dismissing a beautiful and maturing field of physics with "we don't really know anything, so give up" is a sophomoric and pretentious reaction.

    Sure, there's a bunch that we don't understand, but please realize that this is the way science works. Nature is too subtle for us to have canned and precise answers for her behavior. Cosmologists are rightly invigorated by the new data, and ought to be encouraged to research and refute each other's ideas.

  5. Re:Why insist that the universe be "elegant"? by radtea · · Score: 4, Insightful


    It isn't the universe that has to be elegant, but our theory of it. The reason why is that we aren't very smart, and theories with fewer free parameters are a lot easier for us to understand.

    --Tom

    --
    Blasphemy is a human right. Blasphemophobia kills.
  6. Re:Enjoy Fermilab's work while you can by stox · · Score: 5, Insightful

    Well, we could get into a very long and detailed discussion into the value of basic research. I'll point out just a few of the benefits we have received from Fermilab, and leave the rest to you.

    1) Ever hear of a "computing farm"? I'm sure you have. The concept was pioneered at Fermilab.

    2) Ask Bob Young, "Who made the most important confirmation of the value of Linux in the early days?" Couldn't be Fermilab, could it? ( Bob Young was one of the founders of RedHat, BTW. )

    3) Who has done more basic research into superconductors? Who pioneered the use of superconductors? Fermilab.

    4) How many lives have been saved through the use of radiation for treating cancer? Neutron therapy was pioneered at Fermilab.

    5) Do you like American Buffalo? At one time, the only surviving herds were at Fermilab and Yellowstone. Fortunately, they have made a comeback.

    6) Enjoy using the web? Fermilab was the third website on the planet, behind CERN and SLAC.

    I'm sure I have missed a few, but I hope you get the point. We are lucky that our ancestors didn't take the same outlook as you. Some things need a horizon of lifetimes, not just your own. How long was the electron studied? Quantum theory? Radiation? Thankfully, many did, and have left us with a rich environment to live in. I hope the current generation, and those to follow, are wise enough to invest in the future with basic research.

    As for my assertion that money devoted to basic research is dropping at a alarming rate, I will leave this as an exercise for the reader. The results of your studies will be quite enlightening, and quite possibly, terrifying.

    --
    "To those who are overly cautious, everything is impossible. "
  7. Hear Hear by theolein · · Score: 4, Insightful

    Very well put! What really shocks me is that the cowboy mentality is even so prevalent here on slashdot, where many people interested in technology seem to believe that science is of no worth, but God and bombs are.

    I find it simply frightening, because I think it poses a very significant threat to the future of the USA, which is heading down the road of becoming a military power without the brains needed to steer it in a wise direction.

  8. Re:And they call me crazy? by dalyraptor · · Score: 5, Insightful

    No, something that does not appear possible or make sense in nature does not prove that god exists. You cannot put everything that you do not understand down to god, jesus christ!

  9. Re:And they call me crazy? by Glock27 · · Score: 4, Insightful
    Then along comes an argument like this. Gee we science types have data that all our science says doesn't make sense, so to explain it we'll postulate unexplained varying physical sates for the Universe that start for no reason we can nail down and then end for no particular reason we can give (Expansion), invisible energy that no one seems able to find (Dark Matter), or unprovable ripples that just happen to be beyond our ability to find or prove (Cosmic Irregularity Theory?). And our evidence for this? Well it makes our math look good (just as long as you use our equations to do the math with, anyway)

    What you're missing is that science has theories that make predictions about observable things in the real world.

    General Relativity, for instance, led to predictions of 1) longer particle decay times for moving subatomic particles, 2) different orbital period for Mercury than Newtonian mechanics predicted and 3) bending of starlight due to intervening gravitational fields. There are quite famous observations confirming these predictions.

    Similarly, there are quite convincing observations that lend support to the Big Bang theory. Cosmic backround radiation measurements, observed Hubble expansion and observations of galactic evolution as we look further away (further into the past) come to mind as examples.

    That is the difference between religion and science. Science attempts to verify its theories with observed phenomena and experiments. Religion accepts its theories based on blind faith.

    All that said, there is nothing incompatible between science and religion really, as long as your religion doesn't dogmatically insist its wisdom about the real world subsumes observed scientific knowledge (the big trap into which some Christian sects seem to have fallen). In fact, I would argue that quantum mechanics provides an interesting "out" for religion - quantum randomness versus "Gods will". After all, quantum randomness is neither knowable or predictable for us, but it might be exactly enacting Gods will...

    I've often wondered why Einstein said "God would never play dice with the Universe". Perhaps Gods dice are loaded. :-)

    --
    Galileo: "The Earth revolves around the Sun!"
    Score: -1 100% Flamebait