Revision 6 validation limits. Streaming-wave temporal-order thresholds failed at limiter transitions even with resolved references. Optically thick radiation temporal probes remain unresolved under the unchanged 1e-12 measurement guard. Strict stiff coupled temporal tests have not been rerun for revision 6 and remain an open limitation.

Euler and ADER2: direct comparisons

Runtime revision and continuation

Revision 6 with Newton rejection classification and physical initialization for damped Radau recovery. A collectively rejected AP trial is restored and retried at the same timestep using conservative HLL fluxes for all radiation moments; existing timestep halving remains if both trials fail. Physical guards, source equations, tolerances and iteration limits are unchanged. HLL fallback can change diffusion-limit accuracy on affected steps; no universal second-order or AP accuracy is claimed. Same physical model with a qualified realizability recovery change. An AP trial rejection can trigger a conservative whole-step HLL fallback. This may change diffusion-limit accuracy on fallback steps; no universal order or AP claim is made. Earlier completed results retain their original runtime and source hashes. Approved comparisons spanning revisions are explicitly qualified; their differences include runtime-revision effects. Checkpoint continuations retain states from both runtime segments and are excluded from clean timing claims. Conservation diagnostics reset at the checkpoint. Displayed new-ledger budgets cover only the resumed segment, with its own starting totals. The original raw ledger is retained separately; its abandoned post-checkpoint tail is not used.

Per-run runtime identities and qualifications

Each problem compares the two methods at the same refinement level and physical time. Available analytic or limiting-model references are shown alongside both methods, with separate error norms. Partial pairs remain visible while their partner is pending.

The three coupled shock/blast problems have no supplied analytic or digitized numerical profiles. Their method differences and published numerical comparison targets are labeled accordingly; no exact-reference error is invented.

Problem	Available reference	Comparison status
Streaming Wave	exact analytic solution	L2: matched; L3: matched; L4: pending
Streaming Front	exact analytic solution	L2: matched; L3: matched; L4: awaiting matching method
Gaussian Pulse	linearized analytic reference	L2: matched; L3: matched; L4: pending
Equilibrium Sphere	diffusion-limit analytic reference	L2: matched; L3: pending; L4: pending
Subcritical Shock	no supplied analytic or digitized numerical profile	L2: pending; L3: pending; L4: pending
Supercritical Shock	no supplied analytic or digitized numerical profile	L2: pending; L3: pending; L4: pending
Radiating Blast	no supplied analytic or digitized numerical profile	L2: matched; L3: awaiting matching method; L4: pending
Marshak	Su–Olson diffusion reference	L2: matched; L3: matched; L4: pending

Comparison manifest (JSON)