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Hello, the Second Law of Ther thermodynamics can be simply stated thus.

Energy spontaneously tends to flow from being concentrated in one place to becoming diffused

and spread out. It was first formulated to explain

how a steam engine worked. It can explain why a cup of tea goes cold if you don't

drink it and how a pan of water can be heated to boil an egg. But its application has been found to be

rather grander than this. The second law is now used to explain the Big Bang,

the expansion of the Cosmos, and even suggests our inexorable passage through

time towards the heat death of the universe.

It's been called the most fundamental law in all of science, and CP Snow in his two cultures

wrote, not knowing the second law of thermodynamics is like never having read a work of

Shakespeare. So what is the second law? What are its implications for time and energy

and universe and does it appear to be refuted by the existence of life and the theory of evolution?

With me to discuss the second law of thermodynamics is John Gribbin,

visiting fellow in astronomy at the University of Sussex and author of Deep Simplicity, Peter Atkins, professor of

chemistry at Oxford University and author of Galileo's Finger and Monica Grady head of meteorites

at the Natural History Museum. John Grimmin, before we go into detail of the Second Law, can you give us an indication

of how a law which began concerning steam locomotives came to have such a broad application. Can you give us an overview?

But it's because, as you said, it deals with heat. It deals with the flow of heat from one place to another.

That's one manifestation of the Second Law.

And of course that was hugely important in the 19th century as Britain in

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