h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Yeah, I'd like to add some things here, if it's okay...
In fact, this absolute zero point, or 0K (zero Kelvin) as we call it, can never be reached from a thermodynamical point of view. This is, of course, all theoretical, but it's supposed to be some kind of unattainable value, like the speed of light. When I was a physics student (yeah I know, I'm a nutter to study physics, don't tell me), we learned, as a reminder for the thermodynamics, these three rules that in fact sum up the whole of thermodynamics :

first rule : you can never win, you can only break even
second rule : you can only break even at the absolute zero
third rule : you can never reach the absolute zero

We call it 'the laws of the big losers', you can understand why...
It meens the following : in a 'closed system' (ahum, physics... Consider the universe a 'closed system'... Douglas Adams would probably have found it a laughable thought), you can never have more energy than before, the best you can do is have the same amount afterwards (after any process). BUT you can only NOT lose energy (keep the same amount) at the absolute zero, which you can never reach....

I don't know if this is very boring, if anyone finds it interesting, it's just some more words about the subject. I can babble about it for hours, believe me! (you probably do, and I won't demonstrate it, don't worry!!)

So... leaving you to your chilly thoughts...

Oops! Just noticed that there's an entry on the three laws as well... Well, I should've guessed.. Hope I didn't tell something that was already told a dozen times!

I think you lost something here yourself. In a closed system, it is impossible to lose energy (zeroth law).
Maybe you can add a zero law also: everything you lose, is won by someone else (never the other way around, but that's Murphy)

A closed system is one where there is no mass transfer across the system boundaries. Energy transfer can occur.

In an isolated system, no energy or mass transfer occurs.