\begin{frame}
  \frametitle{Mathematical Models}
  
  \begin{block}{}
    A \emph{mathematical model} is a mathematical description of a real-world phenomenon.
  \end{block}
  \vspace{-2ex}
  
  \pause
  \begin{center}
    \begin{tikzpicture}[default,inner sep=1mm]
      \node[align=center,fill=cblue!10,draw=cdblue!20] (world) {Real-world\\problem};
      \pause
      \node[align=center,fill=cred!10,draw=cdred!20,r=world,xshift=18mm] (model) {Mathematical\\model};
      \draw[thick,->] (world) -- node[pos=.5,above] {1} (model);
      \pause
      \node[align=center,fill=cgreen!10,draw=cdgreen!20,r=model,xshift=18mm] (conclusions) {Mathematical\\conclusions};
      \draw (model) -- node[above] {2} (conclusions);
      \pause
      \node[align=center,fill=orange!10,draw=orange!80!black!20,r=conclusions,xshift=18mm] (predictions) {Real-world\\predictions};
      \draw (conclusions) -- node[above] {3} (predictions);
      \pause
      \draw (predictions) |- ++(0,-1cm) -| node[above,xshift=43.5mm] {4} (world);
    \end{tikzpicture}
  \end{center}\vspace{-1ex}
  
  \begin{enumerate}
    \item<3-> Formulate\\
      \textcolor{gray}{Identify independent \& dependent variables, simplify and obtain equations
        (possibly guessing from measurements).}
    \item<4-> Solve\\
      \textcolor{gray}{Apply mathematics such as calculus to derive conclusions.}
    \item<5-> Interpret\\
      \textcolor{gray}{Interpret the model conclusions to predict the real-world.}
    \item<6-> Test\\
      \textcolor{gray}{Compare predictions with reality (revise model if needed).}
  \end{enumerate}
\end{frame}