Wang and Brady Reply:

Figure 1

Sketch of the $\mu \text{−}\varphi$ flow map based on Ref. [2]. The thick curves enclose the flowing region, with the lower curve outlining the arrested region and the upper curve outlining the non-Brownian limiting behavior. The two curves intersect at the shear arrest point $({\mu }_{\mathrm{SAP}},{\varphi }_{\mathrm{SAP}})$. The solid lines represent constant-$\mathrm{\Pi }$ contours at pressures ${\mathrm{\Pi }}_1<{\mathrm{\Pi }}_2<{\mathrm{\Pi }}_3<{\mathrm{\Pi }}_4$. The dashed lines show the constant-$\varphi$ contours at the corresponding at-rest volume fraction. The dash-dotted lines are the constant-viscosity contours.