4

I am writing math book and I am interested how I should print them correctly. I know that the main thing is sameness across the whole document, but I am really interested in ways which are recommended by respectable persons and societies, i.e. Knuth or AMS.

I've already asked this question to find the true.

Now I am editing my book. I come here with the question which spacing is correct between the following variants:

\begin{align}
&\exists m \in \bbR{:}\quad \forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR \mathpunct{:} \forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR : \forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR\colon \forall n \in \bbN\quad x_n \ge m.\\
\end{align}

enter image description here

Personally, I love the first variant, but it seems not so comfortable, so I don't think it is used by typographers.

  • Your title question asks about the space after $\forall x:$, but in your examples you have $\forall n \in \bbN$ and the same space ($\quad$) after each of them. – ShreevatsaR Sep 21 '17 at 15:50
  • @ShreevatsaR let's discuss both cases! –  Sep 21 '17 at 18:10
  • @ShreevatsaR oh I mistunderstood your comment. No, I have different spaces with colon-symbol. I thought that you want to mention that I ask in title about "for all x : " while in question there is "for all x in R :" –  Sep 22 '17 at 08:03
  • As I remember, \quad was recommended before \forall, but I'm unable to find anything online to confirm that, and my reference books are still inaccessible, in boxes. – barbara beeton Jun 08 '22 at 18:17

1 Answers1

1

Here it is suggested that you use ~ in front of \forall. If adapting this, however, the question transforms to what command to use for the colon.

\begin{align}
&\exists m \in \bbR{:}\quad ~\forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR \mathpunct{:} ~\forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR : ~\forall n \in \bbN\quad x_n \ge m.\\
&\exists m \in \bbR\colon ~\forall n \in \bbN\quad x_n \ge m.\\
\end{align}

Outcomes when used with ~

Dan Doe
  • 111