# Using MathJax/TeX in the titles of questions - yes or no?

It have been discussed recently (see, for example, the comments starting here) whether Mathjax (TeX) formulas should be used in the titles at all.

The reasons given for not using them were, for example:

• The titles are not rendered in many places (title of the browser window, hot questions list, viewing your network account, newsletter, filters, ....)
• The titles are easier to understand.
• Using textual description instead of math helps when searching for a question.
• It makes the site slow (depending on you connection and the device you are using).

What do you think?

• Should we try to avoid MathJax in the title completely?

Personally, I disagree with the policy of excluding math from the titles completely. (Although it might be useful on occasions.) My reasons are the following:

• Often it is very difficult to find a suitable textual description
• Formulas in the title help when searching for duplicates. List of related questions may often show you duplicates of the question, but if you see $\sum\frac1{k(k-1)}$ you spot the duplicate immediately, whereas if the question title is a telescoping sum or a sum involving reciprocal triangular numbers, it is not clear what the question is about until you view it.
• I have often used search queries including TeX syntax (see this older discussion). I find them quite effective, especially in combination with tags. So I am not sure that searching for textual description is better than searching for TeX expressions. (Of course, there are many possibilities how to typeset the same expression in TeX. But the same is often true about the description of the problem. But I certainly agree that if the questions can be described in words, this formulation should be included somewhere in the post.) Usefulness of informative titles when searching duplicates has also been mentioned here: More informative titles
• Users here are already used to MathJax in the titles. It would be very difficult to change our habits.

I agree that it is not nice that dollars are displayed in many places, but this minor discomfort does not (in my opinion) outweigh the advantages it brings.

• I think that it should be discouraged, but I certainly don't think it should be banned. There are exceptions to every rule. I especially liked this hack to get a bold word in the title. – user1729 Aug 14 '13 at 12:11
• @user1729 is the second sentence serious or ironic? From the structure of your comment it seems serious. But then to me this seems a prime example of pointless MathJax usage (on top of that, in rendered from I can hardly see the difference even). – quid Aug 14 '13 at 12:26
• @quid It was serious! There is no difference when you are in the question (or, at least, it seems that neither you nor I can see a difference), but in the question list it in noticeable. It is a fine example of saving words by using mathjax! – user1729 Aug 14 '13 at 12:30
• @user1729 Thank you for the clarification. True, in the Q-list it is noticeable; I had not thought of this. Still it feels completely pointless to me, actually actively harmful as I'd prefer something longer over just Top; but even if one does not follow this, I'd say in this context everybody understanding it with Top would have understood it with Top, too. (No MathJax at all would have been needed then!) – quid Aug 14 '13 at 12:45
• @quid Oh, I know it is pointless, I just thought it was cunning! – user1729 Aug 14 '13 at 12:47
• @quid: I always thought of names of categories as part of the mathematical notation which merits the use of MathJax in the title, much like $\Bbb Z$ does. – Asaf Karagila Aug 14 '13 at 21:05
• @AsafKaragila also Z does not "merit" MathJax in a title here in my opinion (if it is clear what is meant); again it might be best just to say integers, depending on precise use-case. Also I would write any time 2x=5 or sin(x)=1/2 in a title here without putting it in doallrs. (To be clear I would never do this is a paper, and also I do not like the idea promoted by some to mix MathJax and not in bodies of posts as the uneven formatting makes things hard to read IMO, but for a SE-title things are different as several considerations should be balanced as explained in OP). – quid Aug 14 '13 at 21:33
• Maybe we need to ask the higher ups for alt-text. That way, if a computer can't render it at all, it would still be fine. – PyRulez Aug 15 '13 at 20:31
• As I've just noticed this can be confusing: My upvote for this question indicates a "yes" to the title question. This in contrast to a "yes" to the question in the body. – Lord_Farin Aug 16 '13 at 12:57
• My upvote for the question merely meant: this is a relevant subject for discussion. – quid Aug 16 '13 at 23:35
• I'm fine with MathJax in titles; what is irksome for me is the use of \displayform or $$ in titles, or titles that are entirely in \LaTeX. – J. M. is a poor mathematician Oct 24 '15 at 18:41 • @J.M.$$ is banned in titles. My bot already tells users to get rid of other display style things. I'll teach him to also comment on all-LaTeX titles. – user147263 Oct 24 '15 at 22:27
• @Normal, I really have been gone for quite a while. A welcome development! – J. M. is a poor mathematician Oct 24 '15 at 22:32

I think to avoid it completely might not be the way to go; and there would also be too much opposition against this.

What I think would be good is that users are aware of some of the downsides of MathJax and formulas in general in titles and take these downsides into account when choosing their titles.

This can also be small things, like, choosing something that is slightly less nice when rendered but not that bad when not rendered; specifically, instructions choosing fonts and operatorname come to mind as things one could sometimes avoid in the title.

Or, say, writing Ext(M,N), without any need for MathJax, instead of putting it into math-mode for the minimally different $\operatorname{Ext}(M,N)$, the latter showing as $\operatorname{Ext}(M,N)$ when not rendered.

As someone who often uses a device that makes MathJax slow, I think MathJax should definitely be allowed in titles, and used for any equations in titles, but avoided when reasonable. When the problem is easily described in words, that is great; otherwise, readable, consistent equations are worth the bother. I would not endorse using MathJax to make bold text in titles (or anywhere else), or putting meaningless bits of it in a title (I've seen titles similar to "Solving for $x$" or "Question about a triangle with sides $a$, $b$, and $c$").

We should allow MathJax in titles on some sites. But we should also solve the problem with hard to recognize titles when they don't get rendered.

Therefore, I suggest developing an algorithm to cast MathJax to plain text, as a fallback solution. The other answer's example $\operatorname{Ext}(M,N)$ would result in Ext(M,N) automatically. And, of course, all fractions can be displayed as (numerator)/(denominator).

Of course this isn't always easy, but I think in very most of all cases where MathJax is used in titles it can be simplified to plain text when not shown on MathJax enabled sites.