Use mathrm + isomath with beamer

I use isomath to make greek letters italic by default. Sometimes I want an upright operator. Then I use \mathrm. It works in the report, but not when trying to use it in my presentation.

This is a minimal non-working example (the \Delta is typeset as a '):

\documentclass[intlimits]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{isomath}
\usepackage{lmodern}
\begin{document}
\frame{Difference in angle is $\mathrm{\Delta}\theta$}
\end{document}


Minimal working example:

\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{isomath}
\usepackage{lmodern}
\begin{document}
Difference in angle is $\mathrm{\Delta}\theta$
\end{document}


So how can I make it work in Beamer?

If you use isomath with beamer, Greek letters will be in a different font than the standard sans serif; for instance

\documentclass[intlimits]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{isomath}

\begin{document}

\begin{frame}

$\alpha+\beta-1$

\end{frame}

\end{document}


prints the disputable output

You may want to use arev, instead:

\documentclass[intlimits]{beamer}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{isomath}

\usepackage{arevtext,arevmath}

\begin{document}

\begin{frame}

Difference in angle is $\upDelta\theta$

\end{frame}

\end{document}


• That is one thing. Another thing is to create a macro that is suitable for operators. Is it possible to renewcommand \matrhm so it creates \upDelta, or is there another more appropriate macro for math operators. I also have the Gamma function, and Exp as in exponential distribution. – user877329 Sep 24 '15 at 8:36

I found that beamer seems to be unable to use greek letters for operators unless either \usefonttheme{serif} or \usefonttheme{professionalfonts} has been used. \usefonttheme{default} fails. Can it be a bug?