It is, and it isn’t - sure, the video shows laminar stretching, but I think a case could be argued that stirring coffee does the same, only faster and less neatly. If the crank in the video was rated clockwise for an hour, the experiment would not.‘unwind’, because homogenous mixing would have occurred.
However, if one were able to apply force in delicate and controlled enough fashion, one would be able to unstir coffee - it just rakes more effort. Maxwell’s Demon can exist; he’s just costly to run.
Well, how about the many worlds hypothesis? Just go to the one where Strom Thurmond won the 1948 Presidential election. In that world it would be illegal to mix coffee and milk.
What happens if you let stirred coffee and milk just sit for a while? Do they seperate? I have no idea because I wouldn’t ever come near enough to a cup of coffee to smell it.
You can do it in our universe – it just takes a very, very, very long time, but there was no timescale constraint in the OP…
I don’t think that whether the universe is particulate is really germane to the question (a lot of people would also argue that quantum field theory is incompatible with a particle ontology).
The key point is really that the second law of thermodynamics necessarily applies to every system as long as it has a certain number of different states to be in, where the ‘ordered’ states are a smaller set than the ‘disordered’ ones. In this case, drawing a state at random gives you a disordered one with a higher probability, and thus, any small change done to the system is more likely to leave it in a less ordered state.
Since any system like the coffee+milk one obeys these requirements – lots of ways to be stirred vs. comparatively small amount of ways to be separated: that’s the reason the stirring itself works, after all --, there’s really no way to find a consistent set of rules that allows some form of ‘efficient’ unstirring, simply by virtue of the laws of probability.
Believe it or not, based on my conception of what I’ve read, I did wonder about field theory as a challenge to atomic/molecular/“particulate” theory, but was too embarrassed too say it.
Whether field theory is a theory or an ontology of quantum physics strikes me in itself as an interesting question. It’s a big subject, I suppose.
Finally, thank you for your simple explanation of entropy as a matter of more or fewer disordered states and probability. But, as you say, with infinite time you get a get-out-of-jail card with constraints of probability.*
*I just thought of a thread query…
Not really. If left long enough (days, weeks) the mixture will spoil and curdle - and will separate into various fluids and clotted solids, but none of them will be fit to be described as either ‘milk’ or ‘coffee’ any more.
Furthermore, milk isn’t just one thing, neither is coffee, for that matter - they’re both mixtures themselves - so even if the components of milky coffee were prone to rapid settling or splitting, it wouldn’t be likely that they would split back to milk and coffee.
Thermodynamics even permits a cup of coffee to be unmixed - people have been saying that entropy can’t be reversed - but it can. Local entropy (i.e. inside a cup) can be reversed by the application of energy (increasing the entropy outside the cup).
A the entropy of a closed system consisting entirely of milky coffee can’t be reversed, but the local entropy of a cupful (an open system) can.
I’ve not tried it, but I intend to now you have mentioned it. Without the milk though - lemon in tea is always without the milk so the same should at least be observed for coffee.
Lemon in milky coffee, yes. Is going to make coffee flavoured cheese curds. Probably not nice.
… Although mature cheese + honey + a sprinkling of ground coffee is nice