Bernoulli's Principle states:

The pressure in a fluid decreases as the speed of the fluid increases.

The Principle accounts for the fact that passing ships run the risk of a sideways collision. Water flowing between the ships travels faster than the water flowing past the outer sides, so the streamlines are more compressed. Water pressure is reduced between the ships. Unless the ships are steered to compensate for this, the greater pressure on the outer sides of the ships then forces them together.

More here.

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I rather wish I had pursued a technical proficiency at university, instead of a catchall degree in economics. Not to say that being a generalist is strictly less desirable than being a specialist. But I reckon there's a stronger sense of satisfaction from the work done as the latter. There must be a delicious power in possessing an esoteric knowledge that necessarily shapes pivotal decisions by virtue of the fact that, like it or not, we're all subject to the laws of physics.