title: Comment on "transition to turbulence in a shear flow".
abstract: In this Comment two main issues are addressed that are pertinent to the interpretation of the transition to turbulence for shear type flows on the basis of transient chaos: the fractal character associated with this transition and the precision needed for a reliable numerical modeling. The analysis is based on a simplified model of 19 degrees of freedom for Couette flow, proposed some years ago by Eckhardt and Mersmann. We conclude that the landscape of lifetimes cannot be fractal, and that a very high numerical accuracy is needed to obtain sound results.
authors.affiliation: Instituto Balseiro, Universidad Nacional de Cuyo--CNEA, 8400 Bariloche, Argentina. fgb2@cab.cnea.gov.ar
authors.forename: Fernando G
authors.initials: FG
authors.lastname: Basombrío
authors.forename: Gabriel
authors.initials: G
authors.lastname: Campo