“…(See [GRS13,Jun13,BR13,JZ13,Mag13,GRS14], where such an idea is used to prove a lower bound for the number of sign changes in various contexts.) In order to bound u n L 1 (β) from below using Hölder's inequality, the authors use the Quantum Ergodic Restriction (QER) theorem [TZ13,DZ13] for the lower bound of u n L 2 (β) and the point-wise Weyl law with an improved error term [Bér77] for the upper bound of u n L ∞ (β) .…”