The Born Rule in a Geometric Block Universe

How can a deterministic block of histories give definite records in Born proportions? The clock supplies a complex register, and the moment map for the phase rotation of a record component gives its squared-amplitude weight. For a reader that selects the least ratio of reference intensity to prepared weight, the uniform law on the simplex is the unique common reference law that gives Born fractions for every positive preparation. If one population of record directions gives these fractions in every orthonormal reader basis, its law is Fubini–Study. Counting equal-resolution initial data in the clock-compatible metric gives Liouville volume. Counting completed records weights each history by how many qualified records it produces. A flat reference law survives this weighting precisely when the mean completion multiplicity is independent of the reference ratios. At one preparation, a reader that records the ideal winner requires only that this mean be equal across winning labels. In the matched four-arm recorder, 88.918% of triggers at the tested preparation yield one label. Among those successes the label distribution differs from the Born vector by approximately 0.000142 in total variation. The general physical justification for the observer count remains open.