Source: cirosantilli/settheory-net
= settheory.net
{tag=Personal knowledge instance}
https://settheory.net/
Where <Sylvain Poirier> dumps his <mathematics> and <physics> brain.
Notably, given the domain name, it is clear that he likes <formalization of mathematics>-stuff, like <Ciro Santilli>.
At first glance, looks a bit dry though, not many examples.