The structure of nearly-optimal quantum strategies for the non-local XOR games
Dimiter Ostrev · Quantum Information and Computation · 2016
We consider the infinite family of non-local games CHSH(n). We consider nearly-optimal strategies for CHSH(n). We introduce a notion of approximate homomorphism for strategies and show that any nearly-optimal strategy for CHSH(n) is approximately homomorphic to the canonical optimal CHSH(n) strategy. This demonstrates that any nearly-optimal CHSH(n) strategy must approximately contain the algebraic structure of the canonical optimal strategy.