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Universe Closer To Heat Death Than Once Thought
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.
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