Hi Neville, I think the aether exists for the simple reason that nothing much in physics makes sense without it. Whether it is frictionless or not is one of the things which we would need to know, but not the only thing. How do its properties vary with distance from the earth? Since the speed of light depends on its properties and since probably other (possibly all) "physical constants" depend on it too we are not in a position to say much at all about the universe without such knowledge. The proud statements of the astronomers are all based on the assumption that the earth is nothing special, and the "laws of physics" as determined in laboratories on earth must be the same everywhere else. A veritable house of cards. Blessings Philip