This question has been on my mind for a while now. Not being a native speaker and coming from a country, where grammatical cases are used to modify nouns and nominal parts of speech, the use of articles does not come naturally to me. Nevertheless, when it comes to definite and indefinite articles in math papers, I see many mistakes, not only grammatical, but also from a pure mathematical perspective.
Two examples from the top of my head:
- An empty set $\emptyset$, should really be the empty set, since there is only one empty set.
- A unique solution, should be the unique solution (although I am not so sure about this one, e.g. "We assume that Eq. (1) has a? unique strong solution")
What are some other common examples where you see the articles being misused?