Neither \boldsymbol{} nor \bm{} work in beamer class

Question

I need to typeset some variables in math mode that are bold and slanted. I tried to use \boldsymbol (\usepackage{amsbsy}) and \bm (\usepackage{bm}). However, neither of them work.

MWE:

\documentclass{beamer}
\usepackage[utf8x]{inputenc}
\usepackage[english]{babel}

\usepackage{amsbsy}

\usepackage{bm}

\begin{document}

\frame{
  \frametitle{Bold}

    \begin{itemize}
     \item $\boldsymbol{R}$ versus $R$
     \item $\bm{R}$ versus $R$
    \end{itemize}

}

\end{document}

The output is as following:

Any suggestions? What did I do wrong?

Answer 1

I can reproduce the issue with TeX Live 2012, not with 2013.

Upgrading to a current TeX Live would be best. A workaround is available anyway:

\documentclass{beamer}
\usepackage[utf8x]{inputenc} % but utf8 would be better
\usepackage[english]{babel}

\usepackage{lmodern}
\usepackage{bm}

\begin{document}

\begin{frame}
\frametitle{Bold}

    \begin{itemize}
     \item $\boldsymbol{R}$ versus $R$
     \item $\bm{R}$ versus $R$
    \end{itemize}

\end{frame}

\end{document}

Loading amsbsy is useless, as bm clobbers the \boldsymbol command making it equivalent to \bm.

Avoid the \frame{...} syntax and favor

\begin{frame}
...
\end{frame}