Quantitative control of solutions to the axisymmetric Navier-Stokes equations in terms of the weak $L^3$ norm

Abstract: We are concerned with strong axisymmetric solutions to the $3$D incompressible Navier-Stokes equations. We show that if the weak $L^3$ norm of a strong solution $u$ on the time interval $[0,T]$ is bounded by $A \gg 1$ then for each $k\geq 0 $ there exists $C_k>1$ such that $| D^k u (t) |_{L^\infty (\mathbb{R}^3) } \leq t^{-(1+k)/2}\exp \exp A^{C_k}$ for all $t\in (0,T]$.