Aligning equals signs across Beamer blocks

I've got a Beamer frame consisting of two blocks that contain some equations:

\begin{frame}
\frametitle{Modell}
\begin{block}{A  $(X_{t})$}
\begin{align*}
\overset{iid}{\sim} \mathcal{N}\left(0, \sigma_{X}^{2}\right)
\end{align*}
\end{block}
\begin{block}{B $(Y_{t})$}
\begin{align*}
Y_{t} &= \sigma_{Y,t}\: \eta_{t}, \\ \sigma_{Y,t}^{2} &= \omega + \alpha_{Y} Y_{t-1}^{2} + \beta_{Y}\sigma_{Y,t-1}^{2} \quad \text{mit} \quad  \sqrt{\frac{\nu}{\nu-2}}\cdot \eta_{t} \overset{iid}{\sim} t\left(\nu\right).
\end{align*}
\end{block}

\end{frame}

I would like like for all equals signs to be aligned, in other words I would like alignment across my two blocks. Normally I would use intertext but since I'm dealing with two block environments I don't think that would work.

Thanks!

This is one possibility. Use of phantom to repeat the longest equation of block 2 in block 1.

Code

\documentclass{beamer}
\usepackage{tikz}
\usetikzlibrary{matrix}

\begin{document}

\begin{frame}
\frametitle{Modell}
\begin{block}{A  $(X_{t})$}
\begin{align*}
\overset{iid}{\sim} \mathcal{N}\left(0, \sigma_{X}^{2}\right)\\
\phantom{\sigma_{Y,t}^{2}} &\phantom{= \omega + \alpha_{Y} Y_{t-1}^{2} + \beta_{Y}\sigma_{Y,t-1}^{2} \quad \text{mit} \quad  \sqrt{\frac{\nu}{\nu-2}}\cdot \eta_{t} \overset{iid}{\sim} t\left(\nu\right).}
\end{align*}
\end{block}
\begin{block}{B $(Y_{t})$}
\begin{align*}
Y_{t} &= \sigma_{Y,t}\: \eta_{t}, \\ \sigma_{Y,t}^{2} &= \omega + \alpha_{Y} Y_{t-1}^{2} + \beta_{Y}\sigma_{Y,t-1}^{2} \quad \text{mit} \quad  \sqrt{\frac{\nu}{\nu-2}}\cdot \eta_{t} \overset{iid}{\sim} t\left(\nu\right).
\end{align*}
\end{block}

\end{frame}

\end{document}
• That looks good but is there a way of getting rid of that extra whitespace after the first equation in block A? – user2249626 Jun 18 '14 at 13:52
• You can strategically allocate \vspace{xxcm} to reduce the white space. For your question, I just tried \vspace{-1cm} inserted between the two blocks and the result is promising. – Jesse Jun 18 '14 at 14:19
• @user2249626 what about \documentclass[t]{beamer}? – s__C Aug 17 '14 at 7:15
• @user2249626 There is surely a skip that align uses; it would be best to \vspace{-\thatskipthatalignuses}, whatver that skip is. – Sean Allred Oct 15 '14 at 19:30

Whit a dynamic placement and whitout \hphantom :

\documentclass{beamer}
\usepackage{tikz,array}
\usetikzlibrary{matrix}

\newlength{\myl}
\newcolumntype{Z}{>{\rule{0pt}{1.4em}\hfill$}m{\myl}<{$}}

\newenvironment{MyAlign}{%
\setlength{\arraycolsep}{1.5pt}%

\smallskip

$\begin{array}{Zcl} }{% \end{array}$

\smallskip

}

\begin{document}

\begin{frame}
\setlength{\myl}{1cm}

\frametitle{Modell}
\begin{block}{A  $(X_{t})$}
\begin{MyAlign}
\begin{block}{B $(Y_{t})$}