Great summary. I also love Prof. V. Balakrishnan's exposition on this topic. The video is long, but he motivates the ideas very clearly and in context: https:

Great summary. I also love Prof. V. Balakrishnan's exposition on this topic. The video is long, but he motivates the ideas very clearly and in context: https://www.youtube.com/watch?v=GOkZs2RZMQY https://www.youtube.com/watch?v=GOkZs2RZMQY.