I am not a physicist but i think "i understand" relativity. By understanding i mean : Be able to give an explaination of the physical phenomenom underliying the relativity formulated by mathematic. Per example : Why can we not simply add the speed of one objet with the other (0.8C and 0.8C per example) when they collide like we do with other non relativistic objects ? If you ask some physicists nobody will give you some reason (this is what mathematic says they tell you...) But the reason i suppose is : Because there is an expansion occuring at light speed of "the space" (or ether) around every particle (atoms etc) Per example : Why has the speed of light (in vaccum) the value we know ? Nobody knows. But the reason i suppose is : Because there is an expansion occuring at light speed of "the space" (or ether). Therefore there are many photons trying to exit the atoms (per example) but only the photons that match the exact expansion rate survive long enought to be detected. Photons are some kind of solitons (they do not loose energy while "surfing" on the expansion wave if they have initialy the right speed). Now, i agree with your attempt to restore the reality of the ether because if you dont do this you will never be able to do space travel. Per example, in this topic some have discussed the fact if the relativistic mass is something we should talk about. Sure! Saying that the kinetic energy replace the relativistic mass is totaly wrong. Kinetic energy remain but the mass within the kinetic energy grown up. A slightly difference.... because this mean that if you eject your LOCAL mass when you approach light speed , you eject THE RELATIVISTIC MASS and therefore have more power to advance (therefore counteract the energy needed to accelerate when you reach light speed value). Mass is relativ...yes., and so the flow of time, but localy, mass or time remain exactly the same as everywhere (this is the foundation of relativity : Universality (not like newtons universal laws that were not universal).