Response to Comment on 'On the Origin of Frictional Energy Dissipation', by B.N.J. Persson

We are grateful to Dr. B.N.J. Persson for his prompt attention to our work (Hu et al. in Tribol Lett, 10.1007/s11249-019-1247-7, 2020). In his Comment, he remarks (i) that near-critical damping of motion in/on solids, one of our main results, is well known for atoms and molecules at surfaces and (ii) that this result may be invalid for real practical cases (Persson in Tribol Lett, this issue). We fully agree with both statements. However, some discussion is justified.