A Bounded Coherence Field with Wright–Fisher / Allen–Cahn Dynamics: Numerical Validation of the RCD C(x,t) Core

We report the numerical validation of a bounded scalar field C(x,t) ∈ [0,1] governed by a stochastic partial differential equation with factored Wright–Fisher / Allen–Cahn dynamics. The field arises in the RCD 2.0 program (Radial Coherential Dynamics, Cerezo, Quantum Benchmark Insights) as an effective coherence variable; here we focus exclusively on the mathematical and numerical properties of its dynamical core. A first attempt at the dynamics, using an unconstrained Landau quartic potential with three free parameters, fails a structural smoke test: the deterministic attractor sits at C* ≈ 1.170820, outside the declared physical domain [0,1]. We document this failure, identify its algebraic root cause, and…