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Thoughts on Imaginary Number Notation

This is a small thing that might seem obvious to a lot of people. It represents a shift in thinking that I found useful, though, so I think it's worth writing explicitely.

Imaginary numbers are often thought of as strange and unnatural, and I think a lot of this can be blamed on notation. There's obviously the names, "imaginary" and "real", which give a bad impression. But even beyond that, the way imaginary numbers are written is kind of weird.

Here's one way you could reinvent negative numbers from scratch, if all you knew was the positive reals. First, you notice that the following equation,

x + 1 = 0

...has no solution. So, you decide to invent a new number, to fill in the blanks. m is defined such that m + 1 = 0.

What happens if you multiply m by 2? Well obviously, you get 2m. So now, we have a whole new set of numbers, the set of all p * m (where p is a good-old positive number) written as m, 2m, 3m, 4m, and so on. Let's call them... the minus numbers.

This is the way imaginary numbers are usually explained. While there's nothing technically wrong with it, it doesn't feel as natural as the way we normally think of negative numbers.

-2 is "negative two". 2i isn't "imaginary two", though, it's "two times i", where i is the imaginary unit. Why don't we just call it "imaginary two"? Give it its own notation, like "~2", or something. Maybe it's because the word "imaginary" is kind of clunky and annoying to say over and over, and all the good notations are already taken. Or, more likely, it's just a matter of tradition. I don't know.

Apparently, Gauss once suggested calling imaginaries "lateral numbers" and reals "direct numbers". I like these names a lot more. 2i is "lateral two". This also presents the opportunity to call reals "literal numbers", which would be extremely confusing.

(And by the way, my ~ notation isn't great, because negative laterals would have to be written -~n or ~-n, which is kinda awkward. You could stack them, but it'd be easy to mistake for an approximately equals (). Putting the ~ above the number, as in ñ would probably be better, but might have its own problems, I don't know.)