[Shiraz (Ray)]

Thanks Steven and Craig.

Yes it is interesting - the glib assertion that entropy can be seen as a decrease in order is pretty much full of holes.

So... entropy (as order) can go up or down at some local scale (local being on any scale from atoms to galaxy clusters?), but at the scale of the universe (whatever that means in an expanding universe), entropy always increases overall. If any force (eg gravity, nuclear) acts to increase order of any part of the universe, it does work, and in the process generates a nett increase in overall entropy, which shows up as heat. For example, a Toyota Corolla is a low entropy object, but the process of making it generates a lot of heat. Excess heat is spread to the rest of the universe by radiative transfer, changing entropy in other places. If the universe was not expanding it would eventually settle to a bland environment with no more entropy increase possible.

Seems to me that trying to explain entropy in terms of the amount of order is a bit too simplistic to get across the true nature of the concept. It also has obvious contradictions - for example, an iceblock melts, but a gold nugget self-assembles - coffee and milk stay mixed, but maganese nodules form by spontaneous separation from sea water etc. etc.

Anyway, will definitely continue to think on this - but very much appreciate the discussion guys. Regards Ray