# Comment on "Energy-time uncertainty relation for driven quantum systems" and "Quantum Speed Limit for Non-Markovian Dynamics". (arXiv:1802.00995v1 [quant-ph])

010402 (2013).] extended the Mandelstam-Tamm bound and the Margolus-Levitin

bound to time-dependent and non-Markovian systems, respectively. Although the

derivation of the Mandelstam-Tamm bound is correct, we point out that thier

analysis of the Margolus-Levitin bound is incorrect. The Margolus-Levitin bound

has not yet been established in time-dependent quantum systems, except for the

adiabatic case.