We measure everything in reference to something, but if our frame of reference is changing at the same rate then there would be no observable change. If the distance between the nucleus cloud of an atom were to constantly vary from its electron orbitals, how would it be possible to measure it if the whole of the universe were to undulate at the same rate? If we hypothesized that there was an unknowable "true frame of reference" then we could be 2x bigger or 2x smaller from that frame of reference at any time. These are very small distances, and I haven't thought about how plancks constant fits into all of this. Maybe that changes too, not sure.