I am using stix fonts to type a formula containing bra-ket notations from quantum mechanics. I observe that the size of a vertical bar is either too small:
\big\}\lvert\psi\rangle
,
or too large:
\big\}\big\lvert\psi\big\rangle
.
I would like to make the \lvert
and the \rangle
symbols be of the same height as \big\}
. Is it possible to achieve this somehow? For a reference I posting the full source:
\documentclass[11pt,a4paper,onecolumn,openright,final]{memoir}
%===============================================
\settrims{0.cm}{0.cm}
\setbinding{1cm} % space for binding
\setlrmarginsandblock{*}{3cm}{1} % spine = edge. Edge=3cm
\setulmarginsandblock{3cm}{*}{1} % upper=lower. Upper=3cm
\checkandfixthelayout
\pagestyle{empty}
%===============================================
\usepackage[]{stix,amsmath}
%===============================================
\begin{document}
Compare different height of vertical bars here
\begin{subequations}
\begin{eqnarray}
g(t-t')&=&-i\langle\psi\lvert T \bigl\{\hat c(t)\,\hat c^\dagger(t')\bigr\}\lvert\psi\rangle,\\
g(t-t')&=&-i\langle\psi| T \bigl\{\hat c(t)\,\hat c^\dagger(t')\bigr\} |\psi\rangle;
\end{eqnarray}
\end{subequations}
and here
\begin{subequations}
\begin{eqnarray}
g(t-t')&=&-i\bigl\langle\psi\bigr\rvert T \bigl\{\hat c(t)\,\hat c^\dagger(t')\bigr\}\bigl\lvert\psi\bigr\rangle,\\
g(t-t')&=&-i\bigl\langle\psi\bigr| T \bigl\{\hat c(t)\,\hat c^\dagger(t')\bigr\}\bigl|\psi\bigr\rangle.
\end{eqnarray}
\end{subequations}
and here $\big\}\big|\psi\big\rangle$.
\end{document}
and the full output:
Any help is much appreciated!
Best Answer
It is a bug in the STIX fonts, I'm afraid.
All delimiters I tried scale perfectly with
\big
,\Big
,\bigg
, and\Bigg
, whereas it doesn't happen with the vertical bar, for which\big|
and\Big|
produce the same size.The
\delcode
of|
with the STIX fonts is"3F03F3
and the characters instix-mathex
have metricsto be compared with the metrics in the Computer Modern fonts when the delcode is
"26A30C
; first the normal variant incmsy10
that hasand then the larger variant in
cmex10
As you can see, the depth is set, and not the height.
A workaround is to redefine
\big
in such a way that it adjusts the choice when|
follows.Making it work with
\lvert
and\rvert
would be possible, but requires pure expansion, so many layers of\expandafter
.