Something like this.

Code
\documentclass{beamer}
\usepackage[utf8]{inputenc}
%\usepackage{pgf,tikz}
\usepackage{tikz}
\begin{document}
\begin{frame}
\begin{center}
\begin{tikzpicture}
\draw[dashed, thick] (0,0) circle (2cm and 1cm);
\draw[line width=3pt] (-2,0) -- (0,5) -- (2,0);
\begin{scope}
\path[clip] (-2.5,\pgflinewidth) -- (2.5,\pgflinewidth) -- (2,-1.5) -- (-2,-1.5) --cycle;
\draw[line width=3pt] (0,0) circle (2cm and 1cm);
\end{scope}
\node at (-1,-2)(s){Sasaki-Einstein};
\draw[line width=2pt] (s) to[bend right] (1,-1);
\draw[line width=2pt] (2,4) node[above]{Calabi Yau} |- (1,2);
\end{tikzpicture}
\end{center}
\end{frame}
\end{document}