I find the above content challenging. I can get some sense of it but I don’t recall using this kind of notation in any of my studies of mathematics in any of my university programs, in which maths was not the main focus. I’m not sure how important it is for me to actually understand it, after all I can no doubt code up a Double Deep Q Network without understanding it, but possibly being a bit autistic I find it hard to just let it go. Besides, it’s the concepts I want but they’re expressed mathematically. Anyway I’ve just signed up for a refresher math course on Udemy which I hope will contain some content that relates to this kind of symbology. It’s a bit hard to tell from reading course descriptions what is actually in them.