*ITAMP Lunch Seminar* *Speaker:* Shengtao Wang (Harvard University) *Date:* Thursday, March 22nd *Time:* 12:00-1:00 pm Includes Pizza. *Title: Quantum approximate optimization: performance and applications with MaxCut and maximum independent set problems* *Abstract: *The Quantum Approximate Optimization Algorithm (QAOA) is a variational method proposed to find approximate solutions for combinatorial optimization problems. However, finding the optimal variational parameters becomes exponentially difficult as the depth p of the QAOA circuit increases. We propose a systematic method to efficiently find (quasi-)optimal variational parameters. Using our proposed approach, we numerically benchmark the performance of QAOA on MaxCut and Maximum Independent Set (MIS) problems up to p≤50. We find that while QAOA generically behaves similarly to quantum adiabatic algorithm (QAA), it can outperform QAA by multiple orders of magnitude in computation time for hard problem instances. We also discuss how the MIS problem can be naturally implemented using systems of trapped Rydberg atoms. *Location: *B-106 @ Center for Astrophysics (60 Garden Street) *Directions: *After entering the lobby of the CfA, turn right to enter the hallway of the B building. In the hallway, turn right again, B-106 will be at the end of the hallway on the left side.