In this paper, QAOA on Maxcut shows symmetries that allow them to restrict their search space intervals. But how do they find such intervals knowing that in the original QAOA angles $\gamma,\beta$ are set on the intervals $[0,2\pi], [0,\pi]$ ?
$\begingroup$
$\endgroup$
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
Appendix A of Sack and Serbyn gives a fairly straightforward explanation wherein the β may be restricted to [-π/4, π/4] for problems exhibiting a Z2 symmetry, such that a global spin flip does not change the cost evaluation; the γ may be restricted to [-π/2, π/2] for unweighted maxcut instances since there is a redundancy about π, while this restriction may not be applied for the larger class of weighted graphs.
Additionally, page 10 of this PDF has a few other nice angle symmetries.
