Recent Theoretical Developments in Strongly Coupled QCD

Heavy-ion collisions involve strongly coupled dynamics of QCD in the entire history of time evolution. We review recent theoretical e orts to meet this challenge, focusing on the two approaches that the speaker has contributed to: 1) Holography or AdS/CFT correspondence, and 2) Symmetry protected phenomena such as those originating from triangle anomaly. The presentation is oriented to non-experts on these fields, and hence relies on intuitive pictures of the methods and the results, without going into specific details.