[Tex/LaTex] Too much white space when using the align-environment

alignequationsspacing

Consider the following example:

\documentclass{article}
\usepackage{amsmath,amssymb}
\begin{document}
    \begin{align}
    \prod a+bm      && \text{is a square in} && \mathbb{R}\\
    \prod a+b\theta && \text{is a square in} && \mathbb{R}[\theta]
    \end{align}

    \begin{eqnarray}
    \prod a+bm      & \text{is a square in} & \mathbb{R}\\
    \prod a+b\theta & \text{is a square in} & \mathbb{R}[\theta]
    \end{eqnarray}
\end{document}

enter image description here

The amount of white spce used by eqnarray is exactly what I want, whereas align adds a (in my opinion) freakishly large amount of white space. So I could just stick with eqnarray, but I've read that I should always (under any circumstances) refrain from using it.

So my question is, how do I make my equation look nice using align?

Best Answer

You could use the alignat environment, which is similar to align.

\documentclass[11pt]{article}
\usepackage[T1]{fontenc}
\usepackage{mathtools}
\usepackage{amssymb}

\begin{document}
  \begin{alignat}{2}
    \prod a+bm      &\quad \text{is a square in} &&\quad\mathbb{R}\\
    \prod a+b\theta &\quad \text{is a square in} &&\quad\mathbb{R}[\theta]
  \end{alignat}
\end{document}

In the »Math mode« document you can find more about advanced math typesetting.

enter image description here

Update:

As requested the same example but with all columns left aligned.

\documentclass[11pt]{article}
\usepackage[T1]{fontenc}
\usepackage{mathtools}
\usepackage{amssymb}

\begin{document}
  \begin{alignat}{3}
    &\prod a+bm      &&\quad \text{is a square in} &&\quad\mathbb{R}\\
    &\prod a+b\theta &&\quad \text{is a square in} &&\quad\mathbb{R}[\theta]
  \end{alignat}
\end{document}

enter image description here

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