Removing Unnecessary Space from Equations within Custom Environments in thmtools

Question

I'm facing an issue while writing my thesis. Whenever a theorem ends with an equation, an additional line is added. I have to use thmtools, and I'm unsure whether I should remove this space from the theorem environment definition or if it needs to be addressed elsewhere. Any ideas?

\documentclass{article}
\usepackage[english]{babel}
\usepackage{amsmath,amsthm}
\usepackage{thmtools}
\declaretheoremstyle[
    spaceabove=6pt, spacebelow=6pt,
    headfont=\normalfont\bfseries,
    notefont=\bfseries, notebraces={(}{)},
    bodyfont=\normalfont\itshape,
    postheadspace=1em, %Space after dot.
    qed={},
]{Theorem}
\declaretheorem[style=Theorem, name=Theorem]{theorem}
\usepackage{lipsum}
\begin{document}
\begin{theorem}
    This is the most beautiful equation
    \begin{align}
        e^{i\pi}+1=0.
    \end{align}
\end{theorem}
\lipsum[1]
\begin{theorem}
    Possibly, the equation
    \begin{align}
        E=mc^2
    \end{align}
    was ahead of its time.
\end{theorem}
\lipsum[2]
\end{document}

Why do you use align* environments for single-line displayed equations? — Mico, Oct 17 '23 at 04:43
I was just trying something different, but $$ doesn't work either. — Daniel Checa, Oct 17 '23 at 04:45
I can replicate the issue you've come across, even when replacing align* with equation*. Is there any way you could make to without the machinery of the thmtools package and, instead, rely on the machinery of the amsthm package to create suitable theorem-like environments? — Mico, Oct 17 '23 at 05:01
What I like the most of thmtools is that you can customize the qed symbol of definitions, examples ant theorems. I think this is would be cumbersome in amsthm. — Daniel Checa, Oct 17 '23 at 05:12

score 1 · Accepted Answer · answered Oct 19 '23 at 17:45

The problem is the key qed={} which is telling thmtools to insert an empty qed symbol. This comes at the line underneath the equation, hence the extra line. You can see this in the simple example below:

\documentclass{article}
\usepackage{lipsum,amsthm}
\begin{document}
\begin{proof}
\lipsum[1][1-2]
\end{proof}
\begin{proof}
\lipsum[1][1-2]
\begin{equation}
\sum
\end{equation}
\end{proof}
\end{document}

So just remove the qed={} from \declaretheoremstyle and the line disappears.

Removing Unnecessary Space from Equations within Custom Environments in thmtools

1 Answers1