Non-Uniqueness of Smooth Solutions of the Navier-Stokes Equations from Critical Data
arXiv:2503.14699 · doi:10.1007/s00222-025-01396-z
Abstract
We consider the Cauchy problem for the incompressible Navier-Stokes equations in dimension three and construct initial data in the critical space from which there exist two distinct global solutions, both smooth for all . One consequence of this construction is the sharpness of the celebrated small data global well-posedness result of Koch and Tataru. This appears to be the first example of non-uniqueness for the Navier-Stokes equations with data at the critical regularity. The proof is based on a non-uniqueness mechanism proposed by the second author in the context of the dyadic Navier-Stokes equations.
54 pages, 1 figure. This new version makes a single change in the acknowledgments