Figure 5: Dependence of the reciprocal permeabilities α and β on the geometry.
Insets: α and β as function of the amplitude a0, dimensionless range ε = r0/λ and number density n = N/V of the metric perturbations. Main plot: Data collapse when plotting α and β as function of the dimensionless average metric perturbation 
for ε0 ≈ 1.3. As can be seen, α and β increase linearly with the average metric perturbation, and the solid lines represent linear fits (see Suppl. Mat. for the fitting coefficients). Consequently, the permeability of the medium decreases with increasing strength of the metric perturbation. In all plots, the error bars originate from fitting the non-linear transport law, |∇P| = αvΦ + βΦ2, to our data.
