# Changing the top margin of the proof environment

In my opinion the proof environment has too big of a top margin. I'd like to have it visually closer to the proposition or theorem it refers to.

I have verified that adding \vspace{-3ex} before a proof environment gets me the result I want. Now, how do I modify the proof environment?

I tried to redefine it, but I don't know the original definition and I didn't find it in my Latex distribution.

MWE:

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{thmtools}
\usepackage[dvipsnames]{xcolor}

\declaretheoremstyle[
spaceabove=\topsep,
spacebelow=\topsep,
name={\color{Blue}Proposition},
]{propsty}
\declaretheorem[style=propsty]{prop}

\begin{document}
\begin{prop}
This is a proposition.
\end{prop}

\begin{proof}
The proof is left as an exercise for the reader.
\end{proof}

\begin{prop}
This is another proposition.
\end{prop}

\vspace{-3ex}
\begin{proof}
The proof is left as an exercise for the reader and it's closer to the
relevant proposition.
\end{proof}
\end{document}


Choosing a negative value for spacebelow didn't seem to do anything. So I decided to change the proof environment.

• we don't know where the definition of proof is either. please provode a small compilable example that shows the problem. and remember, a proof does not always follow directly after the theorem or proposition it refers to; in such a case, the extra space would be useful. – barbara beeton Jun 7 '16 at 14:59
• @barbarabeeton I'm sorry, I added a MWE to the question. – rubik Jun 7 '16 at 15:12

You can have this, for instance:

\documentclass{article}

\usepackage{amsmath}
\usepackage{amsthm}
\usepackage{thmtools}
\usepackage[dvipsnames]{xcolor}

\declaretheoremstyle[
spaceabove=0\topsep,
spacebelow=0\topsep,
name={\color{Blue}Proposition},
]{propsty}
\declaretheorem[style=propsty]{prop}

\declaretheoremstyle[
spaceabove=0.5\topsep,
spacebelow=0.5\topsep,
name={\color{Blue}Proposition},
]{propsty}
\declaretheoremstyle[
spaceabove=0.5\topsep,
spacebelow=1\topsep,
name=Proof,
]{proofsty}
\declaretheorem[style=proofsty]{myproof}
\raggedbottom
\begin{document}
\begin{prop}
This is a proposition.
\end{prop}

\begin{myproof}
The proof is left as an exercise for the reader.
\end{myproof}

\begin{prop}
This is another proposition.
\end{prop}

\begin{myproof}
The proof is left as an exercise for the reader and it's closer to the
relevant proposition.
\end{myproof}
\end{document}


• Very nice. Is there a way to redefine the proof environment so that I can keep that same name? – rubik Jun 7 '16 at 16:35
• Unfortunately I don't know amsthm very well (personally, I use ntheorem). The ntheorem package allows declarations like \renewtheorem or \renewtheoremstyle. – Bernard Jun 7 '16 at 17:12