\documentclass{beamer}
\usepackage{hyperref}

\begin{document}

\url{http://www.google.com}
\url+http://www.google.com+
\url{https://www.example.com/Spaces%20In%20URL/}
\href{http://example.com}{Title text $with math$}
\urldef{\mysite}\url{http://example.com}
\hyperref[asdasd]{asd}

\begin{equation}
  e = mc^2
  \label{einstein}
\end{equation}
Here, I'm referring to \autoref{einstein}.

\section{
  \texorpdfstring{Pythagoras: $a^2 + b^2 = c^2$}{Pythagoras: a² + b² = c²}
}

\subsection{\texorpdfstring{Derivative with metric entries $g_{nm}(t)$}
{Derivative with metric entries}}

\end{document}
