I was watching one of the always-interesting "TED Talks" videos with physicist Sean Carroll giving a lecture on "The Arrow of Time." One point he made that really stood out to me was that entropy, the tendency of mass and/or energy to 'favor' states of disorder, is a common theme throughout much of the universe. He briefly mentioned, however, that certain exemptions to this natural tendency do exist (gravity, biology, and geological sedimentary 'sorting' mechanisms being a few examples). My question is this: If entropy is so prevalent throughout the universe, why do processes such as those aforementioned still arise?

We can reduce local entropy given energy input. Hence, for example, we need to eat, your fridge requires electricity, etc. However your energy source will produce more entropy than you can reduce by using it.

because a reduction in entropy can be favourable provided there is a suffient energy potential.

 

although it is important to not that the entropy reduction is a local effect. for it to happen entropy must increase elsewhere.

... He briefly mentioned, however, that certain exemptions to this natural tendency do exist (gravity, biology, and geological sedimentary 'sorting' mechanisms being a few examples). ...

 

I used to read his serious physics blog posts, and sometimes look at his papers. I found them increasingly speculative and misleading.

 

He's bright, a good talker, and an attractive media personality. His popular book is selling very well. But I stopped paying attention a year or two after he failed to get faculty tenure at Chicago, moved to Caltech, and became increasingly air-castles and media-oriented.

 

If you have the impression that biology somehow goes against thermodynamics that could be because of a slightly imprecise slippery way he talked in a TED situation. Or maybe he didn't say that, but qualified it with some conditions and reservations which didn't come through.

 

I don't want to take the time to listen to carroll's TED so I can't give you a fair assessment, or find out what he really said, versus the impression that he gave.

 

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entropy in the universe (forgetting Carroll popularizations and looking at recent research by some top people) is a great topic!

 

Berkeley Nobel laureate George Smoot has just co-authored an important paper about it.

 

there are exciting new developments going on as we speak.

If you want a link to Smoot's February 2010 paper, just ask.

 

Erik Verlinde's January 2010 paper (entropy and gravity--which verges on the topic of entropy and the universe) also got a huge shock reaction.

I would like a link to Smoot's February 2010 paper