beamer does switch to a sans serif font for math. However, it does not redefine \mathrm. I think it should do so. I have a few formulas that use \mathrm to get upright characters and they look ugly with beamer.
Do you agree or did I miss something?
\documentclass{beamer}
\begin{document}
$abc\mathrm{abc}$
\end{document}
PS. I know how I could get properly looking formulas with beamer. I am not asking for help in this regard. In fact, I am suggesting an improvement (or even bugfix) here and would like to discuss how well the beamer package is written with regard to that issue.
Argument: Other packages that define sans-serif math fonts redefine \mathrm as upright math (sans-serif) font. For example:
\documentclass{article}
\usepackage{cmbright}
\begin{document}
$abc\mathrm{abc}$
\end{document}
cmbright, sfmath and arevmath all redefine \mathrm as upright sans-serif font. So I'd say beamer is the odd one here and should be changed.


\text{abc}and/or\DeclareMathOperator{}{}(both fromamsmath) as appropriate to avoid the issue entirely. – Paul Gessler Jul 14 '14 at 19:49beamermath to look likearticlemath – Werner Jul 14 '14 at 20:10beamer. If anything, it strikes me as buggy to make\mathrmequivalent to\mathsf. (Except in the case where the entire document is to be in sans, I guess. So maybebeamerqualifies there. But I've never liked setting the default roman family to sans either as it just makes the effects of\rmfamilyetc. more opaque.) – cfr Jul 15 '14 at 18:22