# \normalsize inside \author in class amsart

When I try to compile this MWE in Overleaf (although I should rather say "minimal non-working example"):

\documentclass[12pt,reqno]{amsart}

\title{Title}
\author{\normalsize John Doe}

\begin{document}

\maketitle

\end{document}


I get the following errors:

However, the code compiles correctly as expected if instead we substitute \normalsize by \tiny, \scriptsize, \footnotesize, \small, \large, \LARGE, \huge or \HUGE. So what is happening?

It's clearly bad style to put any formatting in \author as the whole point is to have the author name as text with the style specfied elsewhere in the \maketitle setup, so while probably the macros could be made to avoid this error, removing \normalsize is the correct fix.

That said, you can use \protect to avoid the error.

You get a slightly different error in the current release:

! TeX capacity exceeded, sorry [input stack size=10000].
\__bool_quark_recursion_tail:w ...n_tail #2?#3?!->
#1#2
l.8 \maketitle

!  ==> Fatal error occurred, no output PDF file produced!


but with \protect you get no error:

\documentclass[12pt,reqno]{amsart}

\title{Title}
\author{\protect\normalsize John Doe}

\begin{document}

\maketitle

\end{document}


• I'd actually prefer to see the other sizes trigger errors in this context. But then a better error message would be appreciated. Jan 24 at 21:26
• @barbarabeeton bug in amsart that it doesn't make \normalsize robust (even if I'm not supposed to blame you these days) Jan 24 at 21:45

You don't want \normalsize inside \author, because this would affect also the headers in the even numbered pages.

Better to patch \@setauthors which is responsible for typesetting the authors' names.

\documentclass[12pt,reqno]{amsart}
\usepackage{etoolbox}

\makeatletter
\patchcmd{\@setauthors}{\footnotesize}{\normalsize}{}{}
\makeatother

\title{Title}
\author{John Doe}

\begin{document}

\maketitle

\end{document}


• I think to avoid the size changing in the other pages one can use she short title parameter for the \author command of amsart. As in \author[short title]{long title}. Jan 25 at 8:38
• @ElíasGuisadoVillalgordo I still think that patching is better. And not necessary, in my opinion: the author name is less important than the title. Jan 25 at 9:12