it will be oil on fire, and you guys will already downvoted me into oblivion, but the truth is the same, the paper has several typos, which makes in unquestionable that it did not see a spell-checker.
Spell checking math, and in particular LaTeX math, is a complete nightmare. I, for one, find that there are just as many substantive typographical errors after spell checking my papers as before, and all I've done is wasted at a minimum an hour trawling through false positives.
Besides, small typos in a paper that's substantially readable and well crafted, written by someone in a language other than their first, are scarcely a reason to stop reading.
Besides, small typos in a paper that's substantially readable and well crafted, written by someone in a language other than their first, are scarcely a reason to stop reading.