@@ -87,6 +87,13 @@ Q = s(n ⊗ n - \tfrac13 \operatorname{Id}) \quad (s = -3 λ_1 = -3 λ_2, n = ê

- for $`Q ∈ W^{1-\frac1p, p}(∂Ω, 𝒬)`$ orientable to $`n ∈ W^{1-\frac1p, p}(Ω, 𝕊^2)`$ $`ℋ^{d-1}`$-almost everywhere

- $`v_{,k}`$ is the variable $`v`$ differentiated in the direction $`k`$. $`Q_{ij,k}`$ is the $`i-j`$'th component of the matrix field $`Q`$ differentiated in the direction $`k`$. This is not mentioned anywhere!!

- Indeces which appear twice, are summed over, without mentioning it once!! Even when both are lower indeces.

- $`b:𝒬 → ℝP^2`$ (and $`b:𝒬_2 → ℝP^1`$) is isometry between $`𝒬`$ and $`RP^2`$ by