To avoid cancelling another Journal Club talk, I will talk about some old work I did on a possible finite-time singularity in a highly symmetric solution of the Euler equation (inviscid incompressible Navier–Stokes equation). Whether the Euler equation allows a solution with a finite-time singularity is still an unresolved problem in mathematics and fluid dynamics after decades of research. The answer to this problem is highly relevant to the theory of turbulence in fluids. While I worked on this problem many years ago using a highly symmetric flow, I still think I was on the right track but just didn't have the time to continue working on it. Maybe someone in the audience will come up with a new idea to help solving this problem?