- #106
Dale
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This is a good example of a concept that gets generalized. Well before I started doing relativity I had to generalize the notion of "orthogonal" when I learned the Fourier transform and found out that cos functions formed an orthogonal basis for functions. There doesn't even exist any word to distinguish this notion of orthogonality from the less general notion of orthogonality as a 90 degree angle. But nevertheless the presentation of this new concept of orthogonality was sufficiently clear that I didn't get confused.robphy said:(*) for example, what does "orthogonal" fundamentally mean? Does it really mean "90-degrees"?