Chess is mainly about memory and recognizing patterns and implementing those patterns at that exact moment at the chessboard.

So I would definitely think there is correlation between chess and memory. There was a really good documentary about memory called How Does Your Memory Work. Highly recommended, you get to see a glimpse of the workings of Susan Polgar's brain. I might also confuse it with My Brilliant Brain from National Geographic :)

I remember seeing a live post-mortem analysis by Anish Giri. It was just astonishing how fast he can see combinations, yet also how deep those combinations are. And then on top of that throw in a sentence like "Oh, it is not new, it was played in 2006 as well, in that game between him and him". So really, fast thinking, slow thinking, and picking deep into your memory, all at once, seemingly without any effort. That is 2760 ELO for you :)

That's because physics and maths ability is included in the IQ test. If you included lots of chess or chess-like problems than Kasparov would magically rank a lot higher.

Funny that you bring up Feynman, he stated he only had an IQ of 125. High, but probably lower than Kasparov.