Is using the letters of English in math a universal practice?

Question

In the Anglosphere (and in Russia, my home country) some of the symbols used in mathematics are the 26 letters of the English alphabet (52 actually, because there are two cases), and not any other alphabet based on the Latin script. I am aware that Greek and Hebrew, and even the Russian Ш (I call it Russian and not Cyrillic as it was introduced in honor of a Russian mathematician) letters are used in math as well.

My question is: Is this practice universal for all countries, even those that officially use an alphabet based on the Latin script (with letters not present in the English alphabet)? In other words, is there a country in which at least one Latin letter is used routinely in higher (this is important, I'm not asking about high school math) math that would not normally be considered an English letter?

I believe the answer is most likely "yes" (to the first formulation of the question) because the vast majority of mathematical papers and the leading mathematical literature are in English. Plus, English is the global lingua franca. However, I am not completely sure.

N.B. The second time derivative of $o$, i.e. $\ddot o$, is not the same as the German letter 'ö'. I know that this example is from physics, the example is just to get the point across. Also: to those that believe French uses the English alphabet, the Wikipedia article about the English alphabet disagrees (on the right it says "Languages: English" with no French or any other language in sight).

Answer 1

I think the short answer is yes.

Decorated letters from $a, \ldots, z$ are very often used, like $i'$, but diacritic marks as found in French or German writing would be pretty unusual to be used as variables or parameters in math. While $\tilde{n}$ could be used, and it looks Spanish, it really isn't since you could just as easily find $\tilde{x}$ or $\tilde{m}$ in math and those don't correspond to any real language.

I suspect the habit goes back to the wide use of Latin until the 1800s for writing math. So I would say the trend is really the use of letters from Latin rather than from English (allowing that $j$, $u$, and $w$ came later), but I don't want to get sucked into whatever rabbit hole you've fallen into arguing with other people in the comments about what language the alphabet $a, \ldots, z$ belongs to.

The only Cyrillic letter used systematically in math outside of Russia is Ш, although you know that В, Р, and Г may be used by your own instructors if they talk about graph theory.

Answer 2

The answer is NO.

It is not quite correct to say that letters of English alphabet are used. Math uses the letters of Latin. The Latin is not changing since many hundreds of years.

English alphabet is based on Latin. English had letters that are partially different from Latin, see old English Latin alphabet. Later on English alphabet has changed and is currently the same as Latin. Thus, despite they look now the same, it is more correct to say that Latin letters are used, no English.

Besides Latin letters, also Greek letters are widely used in mathematics: In USA, UK, France, Germany, Russia, as well as many other countries.

Greek: Here is an example of internationally understandable notation of limit that uses Greek letters "sigma" and "delta".

German: For instance, for "power set" an old-German letter is used which is similar to Latin P. Here are example 1 and example 2.

Russian: The two widely used **Russian letters are "Ш" (sha-function, from Шафаревич), see example, and "Ж" (one of notations for Lagrange related expressions), see example.

Here is a good article about the history of mathematical notation.