Re: \phi for the golden ratio?

[note from moderator: this will be the last of this thread...]

So far, I have only met three real or complex numbers with universally accepted one-letter symbols: \pi, e, i. Have I missed something?

What about "r" (pronounced "rev"), denoting 2*pi, in the archaic but still widely understood phrase "33 rpm record"? A shame the Greeks chose pi rather than rev, for I think the latter is more fundamental. Paul