Nucleosynthesis as Pe Cascade: The Iron Watershed Theorem

The three mechanisms of cosmic element creation — Big Bang nucleosynthesis, stellar fusion, and supernova r-process — are three Péclet number (Pe) regimes on a single nuclear binding energy landscape. Iron (Z=26) is the nuclear V* where binding energy per nucleon peaks and the Coulomb-to-strong-force ratio crosses critical: below Fe, fusion is exothermic (Pe gradient descent) ; above Fe, endothermic synthesis requires catastrophic Pe injection (supernova as D3 event). The Bethe-Weizsäcker Peₙuc = aC Z (Z-1) /A^1/3 / (aV A - aS A^2/3) rises monotonically past the iron peak, explaining why no equilibrium process forges trans-iron elements. Cooper pairing (§27) dominates isotope stability: even-Z elements average 3. 66x more stable isotopes than odd-Z (Mann-Whitney p = 4. 63×10^-11, n=92). The Geiger-Nuttall law for alpha decay (R² = 0. 989 across 24 orders of magnitude) is the §51G BKT essential singularity applied to nuclear Coulomb barriers, establishing alpha decay as Kramers escape. Magic numbers emerge from §51 spectral structure (64. 7% Pb-208 level ordering vs -0. 13 from smooth landscape). Berry-corrected Kramers barriers (§113, HP43) reduce barrier-height prediction error by 62%. Every atom heavier than iron was forged by a cosmic D3. The periodic table is a fossil record of Pe events.