It's hard to overstate how much of an influence Bertsekas had on the way we think about, analyze, and situate so many RL concepts, from ADP to MPC. I remember almost sleeping through my MPC lecture because I was up late reading his MPC <> Newton Step proofs. RIP to a great man.
We've lost an absolute giant today. RIP Dimitri Bertsekas. His probability and optimization books got me through my masters. Massive loss for the MIT community and the field.