This question stems just from curiosity, as my work is not concerned with mathematics.
What happens if a student doing a PhD in mathematics submits a thesis with a proof of some theorem and the reviewer finds fatal flaws in the proof?
I don't mean small typos but flaws of greater caliber, whose fixing leads to the conclusion that the conjecture one was convinced of proving is completely wrong, or, if gaping contradictions in the proof are found. Can one obtain a PhD with such a flawed thesis?
I assume that in other areas of research even if some results are proven wrong, the PhD can still be awarded on the basis of other results that are present in one's work.
Note, this question differs from this one as here we assume that the thesis has already been submitted and is under review.