Slashdot Mirror

← Back to Stories (view on slashdot.org)

One Big Bang, Or Many?

Posted by ryuzaki0 on from the boggles-the-mind dept.

butterwise writes "From the Guardian Unlimited: 'The universe is at least 986 billion years older than physicists thought and is probably much older still, according to a radical new theory. The revolutionary study suggests that time did not begin with the big bang 14 billion years ago. This mammoth explosion which created all the matter we see around us, was just the most recent of many.'"

3 of 492 comments (clear)

  1. -1 for self-contradiction, -1 for lateness by TripMaster+Monkey · · Score: 5, Informative

    From TFA (emphasis mine):
    The standard big bang theory says the universe began with a massive explosion, but the new theory suggests it is a cyclic event that consists of repeating big bangs and big crunches - where every particle of matter collapses together.
    And also from TFA (again, emphasis mine):
    With each bang, the theory predicts that matter keeps on expanding and dissipating into infinite space before another horrendous blast of radiation and matter replenishes it.

    Now, I'm no cosmologist, but these two descriptions of the theory seem to be in conflict...does the matter in the universe come together in the Big Crunch, or does it fly off into space forever, replenished by subsequent Big Bang events?

    If the Guardian Unlimited doesn't even know what the theory is proposing, why are they reporting it?

    Fortunately, we needn't depend upon Guardian Unlimited for our cosmology news...Nature.com happens to have a much more informative article on the subject. What's especially amusing is that they've had this article since April 26th of 2002.
    --
    ____

    ~ |rip/\/\aster /\/\onkey

  2. See also... by Billosaur · · Score: 4, Informative

    'Cyclic universe' can explain cosmological constant

    --
    GetOuttaMySpace - The Anti-Social Network
  3. Guardian misses the point by JohnnyDanger · · Score: 4, Informative
    The Guardian summary is very poor and mostly misses the point of the new work.

    The cyclic model has been around for several years, and there is plenty I don't understand about it, but it is distinct from the old big bang-big crunch ideas. The "cycle" is the repeated collision between two sub-universes, called branes. We live in one of these sub-universes. Each collision resets our sub-universe with a new big bang... Our universe is constantly expanding; there is no crunch.

    Importantly, the cyclic theory has detectable differences from the standard big bang scenario. For example, primordial gravity waves, detectable through their influence on the polarization of the cosmic microwave background, are present in the standard big bang scenario and absent here. Thus their possible detection by a future microwave experiment could rule out this theory.

    The purpose of this new work is to argue that the cosmological constant (the factor which make the expansion of the universe accelerate) is naturally small and positive in the cyclic model. This is as we observe it. The standard big bang theory does not make a prediction for the size of the cosmological constant (it's just a parameter), while in string theories the expected size of the constant is vastly larger.

    Steinhardt has many materials (including a cartoon movie of the brane collision) on his homepage.