This page reports the convergence and constraint-preservation self-checks for the GDBS BSSN/Z4c numerical relativity engine. A researcher can run the gauge-wave testbed directly in a browser with no install and a deterministic result, using GDBS as a method-development bridge before committing time on an HPC cluster.
Factor-2 self-convergence (Choptuik method, gauge-wave initial data, no exact solution required) measures order 3.946 toward the theoretical 4th order. The Minkowski Hamiltonian-constraint fixed point holds at 1.2e-28 (flat space exact = 0).
Convergence is measured by factor-2 self-convergence using the Choptuik method on gauge-wave initial data, which requires no exact solution: the solution is compared across resolutions differing by a factor of two, and the observed order is read off from the Richardson ratio. On this testbed the measured order is 3.946 against the theoretical 4th order.
Constraint preservation is checked separately on flat (Minkowski) space, where the Hamiltonian constraint is exactly zero. The engine holds the Hamiltonian-constraint fixed point at 1.2e-28, consistent with floating-point round-off about the exact value.
These are numerical-consistency self-checks (convergence order + constraint preservation), standard acceptance tests in numerical relativity, NOT a comparison to measured data. This is a 2D/3D method-development testbed, not a calibrated production waveform.
The check runs deterministically in your browser, no install required.