The Neutron Lifetime Discrepancy and Topological Selection Rules

Title: The Neutron Lifetime Discrepancy and Topological Selection Rules

Author: Alexander Novickis (alex.novickis@gmail.com)

The neutron lifetime discrepancy — a persistent $\sim 4\sigma$ tension between beam experiments ($\tau_{\text{beam}} \approx 887.7 \pm 2.2$ s) and bottle experiments ($\tau_{\text{bottle}} \approx 878.4 \pm 0.5$ s) — has motivated proposals for exotic neutron decay channels involving dark sector particles. We analyse this discrepancy within the Hopf soliton framework, where baryons are multi-sector solitons on the flag manifold $F_2 = \text{SU}(3)/[\text{U}(1) \times \text{U}(1)]$ and dark matter is a vacuum knotting condensate with no stable compact particles (Paper LXVII). We identify three independent topological obstructions to neutron dark decay: (i) the absence of any stable dark particle — compact $H = 0$ knots dissolve in $\sim 10^{-22}$ s, and the vacuum condensate cannot absorb decay products; (ii) conservation of $\pi_2(F_2) = \mathbb{Z} \oplus \mathbb{Z}$ sector charges that cannot be carried by $CP^1$ configurations; and (iii) exponential suppression of topology-changing tunneling. We then investigate the sole remaining loophole — oscillation to a Weyl-conjugate "dark neutron" — and show that the electromagnetic mass splitting ($\sim 161$ keV) exceeds the required $\delta m \sim 10^{-20}$ eV by 26 orders of magnitude. All dark decay channels are closed. The framework predicts $\tau_n = 882$ s from the weak matrix element (Paper XIX), consistent with the bottle world average. The J-PARC electron-beam result ($877.2 \pm 4.4$ s), the first beam experiment to agree with bottles, supports the prediction that the discrepancy is a proton-counting systematic, not new physics.

Tags: #physics #neutron #dark-matter #topology #soliton #beam-bottle #lifetime Difficulty: Advanced Created: 2026-04-11 Updated: 2026-04-13

Key results include:

• Three independent topological locks forbid ALL dark neutron decay channels in the Hopf framework
• Compact dark particles do not exist: $H = 0$ knots dissolve in $\sim 10^{-22}$ s (Paper LXVII); DM is a vacuum condensate
• Weyl dark neutron oscillation fails: EM splitting $\sim 161$ keV is 26 OOM above the required $\delta m \sim 10^{-20}$ eV
• Framework predicts $\tau_n = 882$ s (Paper XIX), consistent with bottles; J-PARC confirms no missing neutrons

Keywords: physics, neutron, dark matter, topology, soliton, beam bottle, lifetime

Series: Paper LXXXVII in the Hopf Soliton Programme