Latex 中的间距问题

Question

我有以下代码

\documentclass[10pt,a4paper]{report}
\usepackage[margin=1in,left=1.5in]{geometry}
\usepackage{lipsum}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{multicol}
\begin{document}
\begin{equation*}
\bf{F}=-\bf{\nabla}\text{V} \hspace{4cm} \text{(-ve is just an ambiguity)}
\end{equation*}
wiriting in terms of potential form we have \vspace{-2mm}
\begin{multicols}{2}
\begin{equation*}
V=V^{ext}+V^{int} ;
\end{equation*}
\columnbreak
\begin{equation*}
F_{i}^{ext}=-\bf{\nabla}_{i} \text{$V^{ext}$}
\end{equation*}
\begin{equation*}
F_{i}^{int}=-\bf{\nabla}_{i} \text{$V^{int}$}
\end{equation*}
\end{multicols}

\vspace{-4.5mm}
where, $V^{ext}$ depends on coordinates of position of particle.
If the force between the particles hold newton law of motion,then $V^{int}$ is a function of relative distance between two interacting particles i.e. 
    \end{document}

我发现，在我使用multicolandcolumnbreak命令的地方，两者之间有足够的间距，这是我不想要的。此外，这太长了，无法在左侧写文本并在右侧写一些注释（即使文本太大或我想在右侧下方写）。

Answer 1

该命令\bf在 LaTeX 中已被弃用超过 25 年。

我修复了几个输入错误，您应该检查差异以便编写更好的代码。

没有必要使用multicol；使用嵌套的aligned。

括号中的注释最好放在行内，而不是放在显示中。并且绝不在论文中写“-ve”（实际上，永远不要写）。

\documentclass[10pt,a4paper]{report}
\usepackage[margin=1in,left=1.5in]{geometry}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{multicol}

\usepackage{lipsum}


\begin{document}

Some text before the equation
\begin{equation*}
\mathbf{F}=-\bm{\nabla}V
\end{equation*}
(negative is just an ambiguity). Writing in terms of potential form we have
\begin{equation*}
V=V^{\mathrm{ext}}+V^{\mathrm{int}},
\qquad\qquad
\begin{aligned}[t]
F_{i}^{\mathrm{ext}} &= -\bm{\nabla}_{i} V^{\mathrm{ext}}, \\
F_{i}^{\mathrm{int}} &= -\bm{\nabla}_{i} V^{\mathrm{int}},
\end{aligned}
\end{equation*}
where $V^{\mathrm{ext}}$ depends on coordinates of position of particle.
If the force between the particles hold newton law of motion,then $V^{\mathrm{int}}$
is a function of relative distance between two interacting particles i.e. 

\end{document}

Answer 2

太期待评论了...

不清楚你的问题是什么。你还有矛盾的：两者之间有足够的间距，我不想要。所以看看，如果以下猜测（在未使用multicolumn环境中）可以帮助您。至少在下面的 MWE 中使用了数学表达式的正确语法：

\documentclass[10pt,a4paper]{report}
\usepackage[margin=1in,left=1.5in]{geometry}
\usepackage{lipsum}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath, amssymb}
\usepackage{graphicx}
\usepackage{tabularx}  % new
\newcolumntype{C}{>{\centering\arraybackslash}X} % new

\begin{document}

    \[
\mathbf{F}=-\boldsymbol{\nabla}V 
    \]
where $V$ is just an ambiguity. Writing in terms of potential form we have 
    \begin{center}
\begin{tabularx}{\linewidth}{*{2}{>{$}C<{$}}}
V=V^{\mathrm{ext}} + V^{\mathrm{int}} ;
    &   \begin{aligned}
    F_{i}^{\mathrm{ext}}  & = -\boldsymbol{\nabla}_{i} V^{\mathrm{ext}}  \\
    F_{i}^{\mathrm{int}}  & = -\boldsymbol{\nabla}_{i} V^{\mathrm{ext}}
        \end{aligned}
\end{tabularx}
    \end{center}
where $V^{\mathrm{ext}}$ depends on coordinates of position of particle.
If the force between the particles hold Newton law of motion,then $V^{\mathrm{int}}$ is a function of relative distance between two interacting particles i.e.
    \end{document}