We consider hypothetical solutions of 3D Euler which blow up in finite time in a self-similar
fashion. We prove that, if the initial data has finite kinetic energy, then the similarity
exponent
which governs the rate of zooming in must be larger than
. If a smooth
globally self-similar blowup profile exists, and this profile satisfies an outgoing property, we
prove that
.
For axisymmetric solutions, we establish the bound
under the sole assumption that the velocity profile is
smooth.
Keywords
incompressible Euler, incompressible Navier–Stokes,
self-similarity, finite time singularity