tl;dr: UC Berkeley math professor and Fields medalist Richard Borcherds has stopped grading homework for correctness because so many students use AI to get top scores, instead grading only on completion. He warns that if AI keeps improving at its current pace, human mathematicians may soon be outmatched entirely, and says he no longer knows whether to recommend students pursue math careers. Berkeley has tested AI detection tools like Turnitin and Rumi but found them inadequate, leaving AI policy to individual faculty discretion.