“…Therefore condition (A.3) holds with τ = 1 2 and Theorem A.1 implies that sup ∈(0,1]U (t, s) L(H r ) ≤ C ′ r t − s r ;in particular condition(3.3) holds with µ = 1. Thus, by Theorem 3.2, Lemma 4.5 (with ǫ = 1/2) and using also (4.1),(4.20), one finds constants K 1 , K 2 , K 3 > 0 such thatU (t, 0)ϕ z0 r ≥ U 2 (t, 0)ϕ z0 r − U (t, 0)ϕ z0 − U 2 (t, 0)ϕ z0 r ≥ K 1 [log(2 + t)] r for all times 2 ≤ t ≤ K 2 log K A Asemiclassical abstract theorem on growth of Sobolev normsWe prove here a semiclassical version of Thereom 1.5 of[31]. Thus consider an Hilbert space H 0 and a positive, invertible, selfadjoint operator K (possibly -dependent) acting on it.…”