Thursday, April 22, 2010

Before The Big Bang

From Eternity to Here

Sean Carroll, a physicist at Caltech, has been on a media tour promoting his latest book, "From Eternity to Here." You might have seen him on "The Colbert Report". Or maybe read the New York Times interview.

After the jump, why it's exciting to see a scientist get some media attention.

Besides his new book (buy it, check it out from the library, borrow it from a friend, whatever, just read it), Carroll is also busy on the lecture circuit. Here, for example, is the introduction to his talk titled, "The Origin of the Universe and the Arrow of Time."

"One of the most obvious facts about the universe is that the past is different from the future. We can turn an egg into an omelet, but can't turn an omelet into an egg. Physicists have codified this difference into the Second Law of Thermodynamics: the entropy of a closed system always increases with time. But why? The ultimate explanation is to be found in cosmology: special conditions in the early universe are responsible for the arrow of time. This talk will be about the nature of time, the origin of entropy, and how what happened before the Big Bang may be responsible for the arrow of time we observe today."
Now, if you are somewhat familiar with cosmology, there's a phrase in that introduction that should set off alarms: "before the Big Bang." Standard high school physics classes have long taught that the Big Bang was the beginning of it all, not just the beginning of matter in the universe, but of space itself, even of time itself. It's as nonsensical to talk about "before" the Big Bang as it is to talk of "north" of the North Pole.

So, what's this Caltech physicist doing using a phrase such as "before the Big Bang?" He's not nuts. He's not misinformed. He's not even particularly heretical. He's just doing what scientists do. He's trying to figure out how nature works. Just as our own 3-D perspective allows us to rise above the Earth and understand why you can't travel "north" of the North Pole, Carroll seeks a perspective that will allow us to put the Big Bang in the context of some larger framework. What that larger framework might be is only dimly understood, but Carroll is not satisfied with the pat answer that the Big Bang is just the way it is and there's nothing we can do to see before it (around it, beyond it, whatever).

Carroll speculates on ideas as complex as multiverses (our own universe is not all there is) and baby universes (we live in one of many such universes that are being born all the time -- drat, there's that word again). He freely admits that he doesn't have all the answers. He's happy if he can just help us gain a clearer understanding of the questions. What he's particularly good at is explaining in educated layman's terms the kinds of problems physicists are struggling with.

For anyone who thinks science is a musty discipline of facts and laws and fixed dogma that the rest of us just have to take on faith, Carroll's daily work proves otherwise. Carroll demonstrates that real, working science is more like a detective story than an encyclopedia. With one big exception. The ending to this detective story hasn't been written yet. The next chapter is still a work in progress. Sean Carroll has a bet that the current chapter will be written before another fifty years passes, but he says there will still be many more chapters to write at that time (drat again).

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