# Why are not all characters in the mathbb{} library and similar, supported?

Today I tried to typeset an F with \mathbb{F}, which my lecturer used in an example in class. This is the result here: $\mathbb{F}$ (empty space). The character is in the standard tex library if I'm not mistaken.

Why is it not supported here? Same applies to \mathfrak{F} (on F and some other characters).

Is the reason for this, that we should refrain from using \mathbb{} unless it's to denote number sets, as in $\mathbb{R}, \mathbb{Z}, \mathbb{C}$, etc.? If this is the case then I understand why it might be handy to not support these other characters so that \mathbb{} is not used wrongly. Though if this is not the case, then I don't see any reason for them not to be supported?

(Unless of course, it's just my browser that won't display them! I sincerely hope that's not the case...).

• I see it just fine. – Qiaochu Yuan Aug 29 '11 at 16:27
• I see it fine too. Could you specify your OS and browser? – Zev Chonoles Aug 29 '11 at 16:29
• $\mathbb{ABCDEFGHIJKLMNOPQRSTUVWXYZ}$ hmm... – J. M. isn't a mathematician Aug 29 '11 at 16:30
• Here's what my previous comment looked like: i.stack.imgur.com/IJpPw.png Could you try (Shift-)Refresh for your browser? – J. M. isn't a mathematician Aug 29 '11 at 16:35
• @Jodles: I have no problem with STIX fonts and Lion. But I use Firefox. Chrome and Safari do have issues. – Zhen Lin Aug 30 '11 at 7:52

I'm using Safari 5.1 with default encoding on OS X 10.7.1. Sorry everyone! I'll fiddle around with my system and try to find a solution -- and I did!

Strange LaTeX fonts in OS/X Lion?

Found the solution here -- apparently the STIX font is messing this up on OS X Lion. Disabling it brought all characters to life!

As it seems like MathJax is trying to use STIX when installed, and something else when it's disabled, maybe there's something the MathJax developer could change? For Apple to change anything we would need a large number of people sending feedback forms, and even then, history suggests they won't do much... I'll send them feedback in any case.

I wonder where the error originates; browser, MathJax or Lion. Nevertheless, now we have a good workaround. Either switch to Firefox (or perhaps Opera?) or disable the STIX fonts for use with Safari and Chrome.

• Actually, it looks like this for me in Safari 5.1, and Chrome. Very strange. Perhaps the version of STIX you have installed is buggy. – Zhen Lin Sep 1 '11 at 4:09
• @Jeff Atwood: Thank you making a post out of my comments! – Jodles Sep 1 '11 at 6:59
• @Zhen Lin: That is odd. I haven't touched any of the fonts since installing Lion... There's still something odd about a few of the letters in your image though. Are the square root signs messed up for you in Safari/Chrome? – Jodles Sep 1 '11 at 7:01
• Yes, the vinculum for square roots is misaligned (and most characters are excessively slanted). It's worth noting that the weird characters in my screenshot are precisely the ones in the Basic Multilingual Plane of Unicode. – Zhen Lin Sep 1 '11 at 7:42
• @Zhen: Good point. Those were also the only characters that would display for me. – Jodles Sep 1 '11 at 8:29