The capstone accepts only a source-bound chain across interference, diffraction, grating, and film checks. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
The audit collects five checked sources
The capstone is a source ledger. It does not recompute a new physics claim; it checks that each earlier source is pinned and accepted.
sources=5
Each source contributes one checked value
The audit table keeps the source values visible before the final accepted bit is read.