In the same vein, you can have split-complex numbers which represent the 2d hyperbolic plane. Also, there are the 4-dimensional generalizations like quaternions, split-quaternions or other related algebra systems.
What's amazing about these systems is that there is usually an Euler relation that holds. Example: e^(i*t) = cosh(t) + sinh(t) for the split-complex.
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In the same vein, you can have split-complex numbers which represent the 2d hyperbolic plane. Also, there are the 4-dimensional generalizations like quaternions, split-quaternions or other related algebra systems.
What's amazing about these systems is that there is usually an Euler relation that holds. Example: e^(i*t) = cosh(t) + sinh(t) for the split-complex.