10 Neumann boundary algorithm

1D Gauge Wave, $\hat W$ system, $\ell_\infty$ error in $g_{xx}$ convergence plots.

The convergence rate for the error in $g_{xx}$, measured at t=50 and t=500, for 10 Neumann boundary algorithm, no renormalization, is:

$${\tilde c_r^{(50)}} = 1.804, {\tilde c_r^{(500)}} = 2.229$$ (17)