# Create definition without title

I would like to know how I make this kind of quote in my text. I know it's not theorem or definition. Thanks for the help

• A quote or blockquote might do. – Oleg Lobachev Dec 10 '17 at 15:30
• I want to create this definition (6) and then reference it in the document – user50098 Dec 10 '17 at 15:34
• @user50098 - Is the "thing" really an equation? If so, just give it an equation number and call it "equation" in any cross-references. – Mico Dec 10 '17 at 16:07
• The block in the picture looks like a multline environment to me. This requires dealing with the line breaks manually though... – wimi Dec 10 '17 at 16:07

This looks like a multline environment where the first/last equations are offset left/right and those in the middle are centred:

\documentclass{article}

\usepackage{amsmath,bm,lipsum}

\begin{document}

\lipsum*[1]
\begin{multline}
p(\tau, j \,\vert\, \bm{x},t)\, \mathrm{d}\tau
\equiv \text{the probability, given $\bm{X}(t) = \bm{x}$, that the \textit{next}} \\
\text{reaction in the system will occur in the infinitesimal time} \\
\text{interal $[t + \tau, t + \tau + \mathrm{d}\tau)$, \textit{and} will be an $R_j$ reaction.}
\label{eq:this_thing}
\end{multline}
\lipsum[2]

\end{document}


You can use \eqref{eq:this_thing} to reference the equation within your document.

• That's surely the way the text in the image was written. This doesn't make the formatting appealing, though. Just to be picky: the documentation of the amsbsy (sub)package states that bm is to be preferred. And the image uses \mathbf, by the way. – egreg Dec 10 '17 at 16:37
• @egreg: I agree. The line spacing in such a textual context should match the surrounding paragraph text at least. I'll update for bm. – Werner Dec 10 '17 at 16:39
• just in case such a construct is embedded in an italic environment, like a theorem, shouldn't \textit instead be \emph? – barbara beeton Dec 10 '17 at 17:50
• @barbarabeeton: Yes, for proper, visible, emphasis. – Werner Dec 10 '17 at 17:51

A proposal

\documentclass{article}
\usepackage{mathtools}
\usepackage{xcolor}
\begin{document}
\setcounter{equation}{5}
\begin{align}
\MoveEqLeft[5] \fcolorbox{white}{yellow}{\phantom{X}}~~p(\tau,j|\mathbf{x},t)\equiv\text{the probability, given
$\boldsymbol{X}(t)=\textbf{x}$, that the \emph{next}} \notag\\
& \text{reaction in the system will occur in the infinitesimal}\notag\\
&\quad \text{interval $[t+\tau,t+\tau+\mathrm{d}\tau)$, and will be an $R_j$
reaction}\;.\label{eq:Defp}
\end{align}

\end{document}


• A screen shot would help ;-) – user31729 Dec 10 '17 at 16:29
• @ChristianHupfer done – user121799 Dec 10 '17 at 16:36

If you want such formatting (I don't like it), at least make the text into a regular paragraph, as those unequal lines are very distracting.

\documentclass{article}
\usepackage{amsmath}

\usepackage{lipsum} % for dummy text

\newenvironment{eqdef}[1][0.8]
{$$\begin{minipage}[b]{#1\columnwidth}} {\end{minipage}$$}

\begin{document}

See~\eqref{foo} for the definition.

\lipsum*[3]
\begin{eqdef}\label{foo}
$p(\tau, j \mid \mathbf{x},t)\,d\tau\equiv{}$the probability,
given $\mathbf{X}(t) = \mathbf{x}$, that the \emph{next}
reaction in the system will occur in the infinitesimal time
interval $[t + \tau, t + \tau + d\tau)$, \emph{and} will be
an $R_j$ reaction.
\end{eqdef}
\lipsum[4]

\end{document}


With the optional argument you can modify the size of the inner minipage.