我使用 得到了一个很长的表达式\underbrace
。由于没有更好的形容词,它导致等式看起来很奇怪。以下是整个等式:
\begin{equation}
\frac{1}{2}g^{\mu\nu}\dm\phi\dn\phi = \frac{1}{2}\left[
\underbrace{g^{0\nu}\d_0\phi\dn\phi}_{g^{00}\d_0\phi\d_0\phi+
\cancel{g^{01}}\d_0\phi\d_1\phi+\cancel{g^{02}}\d_0\phi\d_2\phi+
\cancel{g^{03}}\d_0\phi\d_3\phi}+
g^{1\nu}\d_1\phi\dn\phi+g^{2\nu}\d_2\phi\dn\phi
+ g^{3\nu}\d_3\phi\dn\phi\right]
\end{equation}
它看起来是这样的:
是否可以让箭头从下括号指向方程下方的其他地方,以便主方程不必适应下括号下方表达式的长度?
答案1
您可以使用\mathclap
(或\mathrlap
)mathtools
包裹:
\documentclass[11pt, letterpaper]{article}
\usepackage{mathtools}
\usepackage{cancel}
\newcommand\dn{\mathrm{d}\, n}
\newcommand\dm{\mathrm{d}\, m}
\def\d{\mathrm{d}}% Don't do this
\begin{document}
\begin{equation}
\frac{1}{2}g^{\mu\nu}\dm\phi\dn\phi = \frac{1}{2}\bigl[\,
\underbrace{g^{0\nu}\d_0\phi\dn\phi}_{\mathclap{g^{00}\d_0\phi\d_0\phi+
\cancel{g^{01}}\d_0\phi\d_1\phi+\cancel{g^{02}}\d_0\phi\d_2\phi+
\cancel{g^{03}}\d_0\phi\d_3\phi}}+
g^{1\nu}\d_1\phi\dn\phi+g^{2\nu}\d_2\phi\dn\phi
+ g^{3\nu}\d_3\phi\dn\phi\bigr]
\end{equation}
\begin{equation}
\frac{1}{2}g^{\mu\nu}\dm\phi\dn\phi = \frac{1}{2}\bigl[\,
\underbrace{g^{0\nu}\d_0\phi\dn\phi}_{\mathrlap{g^{00}\d_0\phi\d_0\phi+
\cancel{g^{01}}\d_0\phi\d_1\phi+\cancel{g^{02}}\d_0\phi\d_2\phi+
\cancel{g^{03}}\d_0\phi\d_3\phi}}+
g^{1\nu}\d_1\phi\dn\phi+g^{2\nu}\d_2\phi\dn\phi
+ g^{3\nu}\d_3\phi\dn\phi\bigr]
\end{equation}
\end{document}
我没有 的原始定义\dn
,因此\dm
我为示例提供了一些定义。从您的代码来看,您似乎也在重新定义\d
(就像我在示例中所做的那样,以重现结果);请选择其他名称,因为\d
是一个已经存在的命令。