there is no aether, but the refractive index
of the imperfect vacuum;
Pascal thought that it was perfect, but, then
he also discovered it, experimentally.

please recall that ordinary air has a RI
that is several decimal places close to One; like,
1.00000004, or so.

I'm pretey sure that he didn't plagiarize Lorentz,
although there is some indication that
his wife was better at teh math.

Einstein's SR is no different from LET....He clearly plagiarized Lorentz's
work