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by RunSet 1004 days ago
Dimensional analysis is a method of evaluation invented by physicists to help mathematicians discern apples and oranges from pure numbers.
1 comments

Yes, there is an often overlooked unit 1 at the heart of dimensional analysis.

It counts discrete things that combine as integers, but are not convertible (commensurate) between different instances of the unit, like apples and oranges.

A hen lays 3 eggs a week (1egg/T), and a car factory makes 4,000 cars a week (1car/T). Dimensional analysis says they are both 1/T, but we know they are really not commensurable.

P.S. Things that do not combine as integers: water drops (1+1=1); rabbits (1+1=2^t for some time constant t).