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It's funny, thinking about the whole "God wants things to be down" explanation of gravity.. I remember being very young, let's say about five or six, and reading "What Do People Do All Day" by Richard Scarry. I think - it might have been another book along similar lines, a sort of "this is how the world works" type thing for little kids. Anyhow, there was one page with a dam on it, and I remember thinking for a little while that the water wanted to be lower down, that's how it works.. And so why couldn't the water just creep up over the top of the dam, knowing that in doing so, it would get to fall over the other side afterwards?

Of course, it's sort of possible, under a different set of physical constants, I'm sure. A much more spontaneous and chaotic environment, in which almost speculative fluctuations in energy exist would do the trick. But such an environment wouldn't be appropriate for life - the same mechanism that would allow the water to jump the dam would similarly donate activation energy to a whole host of reactions that we'd prefer didn't happen. The same force that would cause the water to jump over the dam in order to shift it to a lower energy state would similarly combust humans spontaneously so as to reduce them to their lowest energy state - charcoal. Entropy gone mad - it's not ideal.

So the water stays put in the dam. Probably for the best...

I realised this as a small child too - the water doesn't know that it could be lower down on the other side of the dam. I was okay with that, but I always wondered if maybe there was a way to let it know.

A few years later, I discovered what "siphoning" meant, and in a way the world made a little bit more sense. It was possible to effectively let the water know that it could be lower down, and give it the opportunity to remedy the situation. I mean, the mechanics of it are more complex than that, but roughly, that's the general idea.

So that was an exciting discovery right there..

Then a few days ago I found out about a particular form of liquid Helium IV, which acts as a superfluid and "creeps" over surfaces within a system, creating its own self-sustaining capillary effect. Effectively the superfluid can "seek out" areas where the fluid can exist at a lower energy state, and transfer the fluid to those areas. It's a really rather brilliant effect - within a closed system, it allows the level of the liquid helium to equalise in its optimal state. I can't describe how intellectually satisfying it was to find this out - my five year old self would have been thrilled to find out that superfluids can actively seek out the lowest energy state for themselves. They are self-siphoning.

I love the universe...