The parallel repetition theorem states that for any two-prover game, with value $1- \epsilon$ (for, say, $\epsilon \leq 1/2$), the value of the game repeated in parallel $n$ times is at most $(1- \epsilon^c)^{\Omega(n/s)}$, where $s$ is the answers' length (of the original game) and $c$ is a universal constant. ... more >>>