Dear all,
Following my previous updates, I would like to report progress on applying the samplers to the GW150914 binary-black-hole (BBH) spacetime on a 3- level Carpet AMR mesh -- the first fully realistic (non-stationary) test case for the geodesic probe.
Completed this week: the aei sampler (metric_interp=aei, time_interp= linear). The 100-particle geodesic run at 256 resolution reproduces the reference run exactly: all compared steps (t = 0 .. 0.3356, 40 particle blocks of 100) agree to full double precision, with 0 dropped particles and 0 NaNs. At 128 resolution the t=0 block likewise matches a 2048 reference to full precision, and the residual difference at t=0.2753 (position ~5e-4) is consistent with the expected convergence of the sampler. In short, aei on the GW150914 AMR evolution is now verified and reproducible.
Still under test (no result this week): the remaining samplers (local27 and its time-linear variant l27lin, plus carpet) on the BBH AMR mesh. In particular l27lin shows particle loss in the strong-curvature region near the horizons; I am debugging the metric/Christoffel sampling path there. I have no conclusion to report on them yet.
So this week's deliverable is a single, clean result: aei on GW150914 is verified reproducible. The other samplers on the BBH AMR remain under verification, and I will report a concrete result once they pass.
As before, I am most comfortable continuing in writing. Any questions or suggestions on the strong-curvature path are welcome.
Best regards, Yuhua Li