A math lover :)
Resource for calculus https://math.stackexchange.com/questions/901622/single-variable-calculus-reference-recommendations/901623#901623
All time favourite:
https://astronomy.stackexchange.com/questions/36810/mathematical-analysis-of-blackhole
https://physics.stackexchange.com/questions/304799/definition-of-the-spacetime-interval
The discussion on which I have certainly fell in love: https://astronomy.stackexchange.com/questions/2240/what-is-a-singularity-what-is-at-the-center-of-a-black-hole-specifically-regar?rq=1
One of my favourite questions: https://math.stackexchange.com/questions/3716935/number-of-ways-to-select-the-election-dates/3716948#3716948
One of my useful questions: https://math.stackexchange.com/questions/3726741/find-the-value-of-a-02-a-12a-22-dotsa-2-n2