This question already has an answer here:
I'd like to typeset vectors as bold letters; I've tried
\mathbf and then
\bm, but I don't like the italicization of
\mathbf doesn't work on Greek. I also really like the default, Computer Modern font.
I've read the standard question on the subject, but the
upgreek commands clash with Computer Modern. The package
textgreek doesn't seem to fit the bill, because it complains if I try to put its commands in math mode. There are very many solutions here and here, but all of the ones I've checked change the font of the entire document, or demand I change my LaTeX compiler. (I see one comment exchange: "But won't this change the font?" "Yes, of course.")
All I want is a few decent looking letters with as few changes or extra packages as possible. Is there a short or ideally one-line solution?