Public statement.
The combined main theorem. For every α ∈ (0, 1/3) there is one divergence-free,
ℤ²-periodic drift b in C⁰_t C^{0,α}_x ∩ C^{0,α}_t C⁰_x on [0,1] × 𝕋² such that:
(i) anomalous dissipation (Theorem 1.1 of Armstrong–Vicol) holds for every mean-zero H¹ datum,
with a rate ϱ depending only on ‖θ₀‖_{L²}/‖∇θ₀‖_{L²};
(ii) uniform time regularity (Remark r.LeBron.2): for every κ ∈ 𝒦 = ⋃_j [κ_j/2, 2κ_j], where
κ_j → 0 and 4κ_{j+1} < κ_j, every solution satisfies
‖θ^κ‖_{C^{0,μ}([0,1];L²)} ≤ C‖θ₀‖_{H¹};
(iii) non-uniqueness of vanishing-diffusivity limits (a corrected form of Proposition
p.no.selection.principle): there is a class 𝒟 of smooth, mean-zero, nonzero data, closed under
nonzero scalings and containing cos(2πn x₁) for infinitely many n, such that for every
θ₀ ∈ 𝒟 the solutions along κ_{2j}/2 and along 2κ_{2j} converge in C^{0,ν}([0,1];L²) to
two weak solutions of the transport equation whose L² norms differ at some time.