Reply to: On yoctosecond science

[...]after this displacement, the residual scattered light arrives with a delay (or an advance) at the target nuclei (Fig. 1d). In the latter field, the discussion in terms of relative pulse delays and corresponding phase shifts is firmly established. [...]the discussion of our Mössbauer experiment in the same language of mutual delays uncovers and strengthens the link between the two fields. In our case, for example1, one can implement versatile control operations that act on the target nuclei and can exchange this second target without affecting the controlling X-rays. [...]our control method is general and can be applied to any target. In our experiment, imperfections in the motion of the control sample may impede the temporal coherence of the scattered light. [...]we determine the delay stability in ref.2, and find it to be on the few-zeptosecond level - much shorter than the X-ray oscillation period T = 287 zs, as required for coherent control.