[Tex/LaTex] Inconsistent margins using columns in beamer

beamermarginstwo-column

Compare the two slides generated by the following code.

\documentclass[t]{beamer}
\usepackage{lipsum}
\begin{document}
\begin{frame}
  \lipsum
\end{frame}
\begin{frame}
  \begin{columns}[T]
    \begin{column}{0.5\textwidth}
      \lipsum
    \end{column}
    \begin{column}{0.5\textwidth}
      \lipsum
    \end{column}
  \end{columns}
\end{frame}
\end{document}

Notice how, in two-column mode, the side-margins are smaller, and the top margin is larger. This makes the layout on my slides inconsistent when I mix a two-column and one-column layout, particularly if I do so on the same slide.

How do I get LaTeX to stop messing with margins in two-column mode?

Thanks,
-Willard.

P.S.: In case someone else has the same issue: In two-column mode, if I had an image in one column, then placing a theorem in the other column would move the image. I traced this issue to

\setbeamercolor{structure}{...}

which apparently does more than just colour things. To change colors, use

\usecolortheme[...]{structure}

instead.

Best Answer

Try [onlytextwidth,t] instead of [T] (p. 125, beamer manual):

enter image description here

\documentclass[t]{beamer}
\usepackage{lipsum}
\begin{document}
\begin{frame}
  \lipsum[6]
\end{frame}
\begin{frame}
  \begin{columns}[onlytextwidth,t]
    \begin{column}{0.49\linewidth}
      \lipsum[6]
    \end{column}
    \begin{column}{0.49\linewidth}
      \lipsum[6]
    \end{column}
  \end{columns}
\end{frame}
\end{document}

Related Solutions

[Tex/LaTex] Block in column has a too big margin from top

It's a feature: a switch between vertical and horizontal mode.

Here is your MWE with a call to \leavevmode:

$example with a call to <code>\leavevmode</code>$

\documentclass[18pt]{beamer}
\usetheme{Frankfurt}

\begin{document}

\begin{frame}[t]{Frame with Columns}
 \begin{columns}[t]
   \column{0.4\textwidth}
   \begin{block}{Block 1}
     Text here
   \end{block}
   \column{0.4\textwidth}
   \begin{block}{Block 2}
     More text here
   \end{block}
 \end{columns}
\end{frame}

\begin{frame}[t]{Frame without Columns}
  \leavevmode\begin{block}{Block}
    Even more text here
  \end{block}
\end{frame}

\end{document}

As suggested by percusse, to keep a minimal top margin you can use \vspace with a negative distance (here, I choose -\baselineskip):

second version

\documentclass[12pt]{beamer}
\usetheme{Frankfurt}

\begin{document}

\begin{frame}[t]{Frame with Columns}

  \vspace{-\baselineskip}
  \begin{columns}[t]
    \column{0.4\textwidth}
    \begin{block}{Block 1}
      Text here
    \end{block}
    \column{0.4\textwidth}
    \begin{block}{Block 2}
      More text here
    \end{block}
  \end{columns}
\end{frame}

\begin{frame}[t]{Frame without Columns}
  \begin{block}{Block}
    Even more text here
  \end{block}
\end{frame}

\end{document}

[Tex/LaTex] How to top align itemize in two columns in beamer

Use some \vphantoms in the itemize to the left so items on both environments have the same height:

\documentclass{beamer}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}
\usepackage{graphicx}
\usepackage[caption=false]{subfig}
\usepackage{braket}
\usepackage{geometry}
\usepackage{empheq}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage[backend=biber,url=false,doi=false,isbn=false,firstinits=true]{biblatex}

\begin{document}

\begin{frame}{Angular Spectrum Method}{Free Space Propagation}
    A constant index medium such as free space is: 
    \begin{itemize}
        \item isotropic \pause $\Rightarrow$ diagonal permittivity, permeability tensors \pause
        \item spatially uniform \pause $\Rightarrow$ relative permittivity and permeability are constants equal to 1 \pause
        \item Source free \pause $\Rightarrow$ $\mathbf{J} = 0$, $\rho = 0$
    \end{itemize}
    \pause
    \begin{columns}[T]
    \begin{column}[T]{.5\textwidth}
        \vspace{0pt}
        \begin{itemize}
            \item<7-> Polarisation Independent!\vphantom{$ \dfrac{ \partial^2 \mathbf{E} }{ \partial t }$}
            \item<8-> Modes are plane waves\vphantom{$A_\mathbf{k} e^{ \mathbf{k} \cdot \mathbf{r} }$}
        \end{itemize}
    \end{column}
    \hfill
    \begin{column}[T]{.5\textwidth}
        \begin{itemize}
            \item<7-> $ \nabla^2 \mathbf{E} - \mu_0 \mu_r \epsilon_0 \epsilon_r \dfrac{ \partial^2 \mathbf{E} }{ \partial t } =  0 $
            \item<8-> $ E_i = \sum_\mathbf{k} A_\mathbf{k} e^{ \mathbf{k} \cdot \mathbf{r} } $
            \item<8-> $ \left( \dfrac{ 2 \pi n }{ \lambda } \right)^2 = k^2 = k_x^2 + k_y^2 + k_z^2 $
        \end{itemize}
    \end{column}
    \end{columns}
\end{frame}

\end{document}