Tao constructs a modified three-dimensional Navier-Stokes equation that preserves two key structural features of the true equation—the energy identity and function space estimates for the nonlinearity—yet admits finite-time blowup solutions. The modification uses an averaged bilinear operator built from rotations and Fourier multipliers. The result formalizes a "supercriticality barrier": proving global regularity through abstract upper-bound methods alone is impossible, because any such proof would also apply to this modified equation where solutions provably blow up. Technically, the blowup mechanism relies on designing an ODE system using "quadratic gates" arranged in a circuit-like structure that channels energy through frequency scales exponentially fast—analogous to a self-replicating von Neumann machine. Tao speculates the construction hints at a path to actual Navier-Stokes blowup, though only for very special initial data. The source text is a blog post by Tao explaining his arXiv paper; it's dense exposition rather than peer-reviewed publication, so verification depends on the formal paper itself.