Figure 8

Figure 8: Comparison between boundary conditions in case (a) (solid) and case (b) (dotted); see the body of the text for more details. Four different resolutions are shown: (Nr, L) = (21,8), (31,10), (41,12 ) and (51,14), where N r and L refer to the number of collocation points in the radial and angular directions, where Chebyshev and spherical harmonics are used, respectively. Left panel: the difference Δ 𝒰 between the solution with outer boundary at R = 41.9M and the reference solution. Right panel: the constraint violation 𝒞 (see [366] for precise definitions of these quantities and further details). Courtesy: Oliver Rinne. Reprinted with permission from [366]; copyright by IOP.