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Universe Closer To Heat Death Than Once Thought

Posted by Soulskill on from the we're-doomed dept.

TapeCutter writes "In a paper soon to be published (PDF) in the Astrophysical Journal, Australian researchers have estimated the entropy of the universe is about 30 times higher than previous estimates. According to their research, super-massive black holes 'are the largest contributor to the entropy of the observable universe, contributing at least an order of magnitude more entropy than previously estimated.' For those of us who like their science in the form of a car analogy, Dr. Lineweaver compared their results to a car's gas tank. He states, 'It's a bit like looking at your gas gauge and saying "I thought I had half a gas tank, but I only have a quarter of a tank."'" Fortunately, that quarter of a tank will still get us as far as we need to go and then some.

4 of 237 comments (clear)

  1. As far as we need to go? by Steve+Baker · · Score: 4, Interesting

    > Fortunately, that quarter of a tank will still get us as far as we need to go and then some.

    And where is it that we're going?

  2. The universe could go back to low entropy by Viol8 · · Score: 4, Interesting

    Just because the laws of physics IN THIS UNIVERSE prevent that doesn't mean it can't happen since by definition the low entropy state the universe started in was created (in some form) by alternative laws of physics possibly outside this universe since the laws we know didn't exist at that point.

    There's no reason why these alternative physical laws couldn't suddenly kick back in when the universe reaches a certain entropy state and start to reverse the whole process back to zero. Some people would say time would then be going in reverse but this doesn't need to be the case.

  3. no problem by ArcherB · · Score: 4, Interesting

    Considering that red dwarfs are expected to last trillions of years (no red dwarf has ever died. The universe is too young), we just need to move to a planet around one of them, assuming they have habitable planets.

    --
    There is no "I disagree" mod for a reason. Flamebait, Troll, and Overrated are not substitutes.
  4. two possible futures now cut shorter.... by rubycodez · · Score: 5, Interesting

    Star formation is believed to end about 10^14 years from now, the total entropy of universe only affects events after that. Not a worry. If protons decay with 10^32 year half-life, then practically all nucleons decay after 10^40 years, which leaves all black holes to evaporate after about 10^99 years.

    If protons don't decay as we suspect, then universe slowly tunnels to iron-56, (light nuclei via fusion and heavier via fission) in about 10^1500 years, which coalesce into black holes or neutron stars in about 10^10^76 years (yup, double exponent).

    So quite frankly, this bit about more entropy means little for life as we know it, though if life can arise by some heat-engine powered means (due to temperature differences only). still the time scales are staggering.

    but all mute if Big Rip is possible, we might only have 22 billion years left!:

    http://en.wikipedia.org/wiki/Big_Rip