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by sacrosancty 1359 days ago
Thanks for writing that. While I don't automatically believe it all, I think it's important to see what's arbitrary and what's natural in our units. I've struggled with the Hz vs rad/s before and I think I resolved it by including the cycle as a quanitity, so Hz = cycle/s and rad/s = 1/s. You don't seem to agree and I'm not confident of my decision, but it's now part of a big technical debt :P

A clear sign of how wrong people can be about the naturalness of units is Avogadro's constant which was recently demoted from a measured value to an exact arbitrary value. Chemists often believe that N_A, moles, atomic mass units, etc. are all somehow important or fundamental and don't realize that it's all based on a needlessly complicated constant with an (until 2019) needlessly complicated definition that could have just been a simple power of 10 if history had gone differently. Luckily the people defining SI have finally moved away from the old two independent mass units to just the kg that can now be exactly converted to atomic mass units by definition.