Math mode adds extra horizontal space after superscripts. I have listed various options for removing it in the MWE. I would like to know if there is any recommended way of doing this in amsmath
.
I am thinking of using \negthickspace
for now. However, I am interested to know if that looks too tight for a professional typographer. As my thesis has a lot of superscripts, this small decision is going to make a lot of difference in the look and feel of the whole document.
MWE:
\documentclass[preview]{standalone}
\usepackage{amsmath}
\begin{document}
%\noindent
$R(u,x) = R(u^{*},x)$
$R(u,x) = R(u^{*}\!,x)$
$R(u,x) = R(u^{*}\negmedspace,x)$
$R(u,x) = R(u^{*}\negthickspace,x)$
$R(u,x) = R(u^{*}\!\!,x)$
\end{document}
EDIT:
The default behaviour of latex looks more reasonable when you write $u^{*}\negmedspace \Sigma &= R(u^{*}\negmedspace,\Sigma)$
which yields
So if a global macro is to be written to introduce this negative spacing then it has to take into account the character that comes after the superscript. I don't know if this is possible or advisable.
\!
looks best.