Reply to Comment on Faceting and flattening of emulsion droplets: a mechanical model by Haas et al

In their Comment [arXiv:2102.03842], Haas et al. advance two hypotheses on the nature of the shape transformations observed in surfactant-stabilized emulsion droplets, as the theoretical models that us [Phys. Rev. Lett. 126, 038001 (2021)] and others [P. A. Haas et al. Phys. Rev. Lett. 118, 088001 (2017), Phys. Rev. Research 1, 023017 (2019)] have introduced to account for these observations. (1) Because of the different surfactants used in experimental studies, the physical mechanisms underpinning the shape transformations may, in fact, differ in spite of the extraordinary resemblance in the output. (2) The theoretical models are mathematically equivalent by virtue of the small magnitude of the stretching and gravitational energies. In this Reply, we argue that neither of these hypotheses is well justified.