Anyone interested in this topic should be sure to follow the various links on the page. One of my personal favorites is the Compactness Theorem: https://en.wik

Anyone interested in this topic should be sure to follow the various links on the page. One of my personal favorites is the Compactness Theorem: https://en.wikipedia.org/wiki/Compactness_theorem https://en.wikipedia.org/wiki/Compactness_theorem .