Resumen de An example pertaining to the failure of the Besicovitch-Federer structure theorem in Hilbert space

Thierry De Pauw

• We give an example, in the innite dimensional separable Hilbert space, of a purely unrectiable Borel set with nite nonzero one dimensional Hausdor measure, whose projection is nonnegligible in a set of directions which is not Aronszajn null.