# How to pronounce $\mathcal{E}$?

How to say $\mathcal{E}$ when we are speaking about mathematics? Can I call it "curly E"?

And also how to pronounce $\mathcal{A}$ and $\mathcal{B}$ and $\mathcal{P}$ and so on?

• Why should anyone bother answering if you're planning to delete their answer? – Angina Seng Jan 21 '18 at 3:29
• > I may delete it once I get the answer. – user223391 Jan 21 '18 at 3:37
• This is something you can google for – QuIcKmAtHs Jan 21 '18 at 3:45
• I cannot type strange letters on google – Ma Joad Jan 21 '18 at 3:48
• For future reference, you cannot delete a question once someone has spent time and energy answering it. – gen-z ready to perish Jan 21 '18 at 4:24

It depends on your audience and the context. In physics, $\mathcal E$ usually denotes emf, so you would say that. In set theory, $\mathcal P$ usually denotes a power set, so you would say that. Otherwise, just do your best to describe it in a manner that your audience would understand. “Curly” or “calligraphic” works fine in my opinion.

Side note: You actually can type $\mathcal E$ into Google if you use the Unicode character ℰ (U+2130).

A useful resource for "speaking" mathematics is The Handbook for Spoken Mathematics by Lawrence A. Chang. This book suggests that we should use a description of the font or script, plus the name of the letter (see pages 3–5). Hence $$\mathcal{E}$$ might be read as "calligraphic capital $$E$$". In most contexts, this would likely be overkill and require too much talking—I gather that much of the intent of the Handbook is to give a guide for instructors of blind students. Hence an abbreviated "calligraphic E" might also be appropriate, as we can rely on students to read / copy what is on the board in most circumstances.

Other thoughts (including those above):

• Follow the handbook: "calligraphic capital [letter]" or "calligraphic [letter]".
• Describe the letter more loosely: "script [letter]", "curly [letter]", or "cursive [letter]".
• Use TeX: "mathcal [letter]" or "cal [letter]".
• Don't Sweat It: "[letter]".
• Name the Symbol from Context: as suggested in this answer, the symbols may have specific meaning in a given context. For example, $$\mathcal{H}$$ is "the Hilbert space H", and the symbols $$\mathcal{X}$$ and $$\mathcal{Y}$$ are "the Banach spaces $$X$$ and $$Y$$".

 This is what I find myself doing most often. The symbol $$\mathscr{H}$$ is "math script H", while $$\mathfrak A$$ is "mathfrak A". This sometimes causes me problems in classrooms where I am dealing with students who don't know TeX, but has never been an issue when talking with my peers.

 This option will often be the most appropriate. For example, the space of distributions $$\mathcal{E}'$$ is just "E prime". There may be potential for ambiguity, but in many, many contexts, it just won't be a problem. I mean, do we often make a big deal about an element $$x$$ in a space $$X$$? Sometimes we carefully speak the letters out loud, but I find myself saying "Let eks be an element of eks..." more often than I care to admit.