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This paper restates the register's oldest weakness. P33 has said since the beginning that the light end (, ~0.16%) is the ledger's weak spot. That framing rests on the fractional miss being the right thing to look at, and the absolute miss is the one that matters. The ledger's absolute miss is roughly constant across the whole table: median 1.9 MeV, essentially uncorrelated with size . The fractional miss everyone quotes is that constant divided by the mass, so it falls as ~1/mass — which is why per-element misses follow a power law in Z with exponent for every family of elements alike (noble gases: exponent at ; all elements: ; the agreement is the tell). The light end was never a separate disease. It is the same few-MeV error, divided by a small number. [earned — the diagnosis; runner below] And when the illusion is stripped, exactly one object remains: helium-4, missed by 11.6 MeV — six times the table's median absolute error — twice what the power law (fitted without helium) predicts for its size. Not "light so it looks bad." Genuinely anomalous, alone. This record holds one paper on its own and is refreshed every couple of months. The complete deposit, 10.5281/zenodo.21788037, holds every paper with its code and data and is updated first; for the newest version of this paper, go there.
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James Norman Ibbotson (2026) studied this question.
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