Tom2, I have nothing against the concept of relativity. I can understand how physical equations can exist where the absolute properties in them can either negate each other, or can otherwise be superfluous in the equations. For example, gravitational acceleration on the surface of the Earth is equal to around 10 m/s^2 regardless of the mass of the object that is accelerating. In this case, the mass of the accelerating object is superfluous, but that doesn't mean that the object does not have mass. The same thing applies to relativity, just because a property is superfluous in an equation doesn't mean that property doesn't exist. I would expect to live in a universe in which absolute properties in some physical equations are superfluous, while in others they are absolutely necessary. For example, in an inertial frame of reference, I will admit that the absolute values in most of the physical equations dealing with the interactions in that frame may be superfluous, but that doesn't mean that they all have to be. What I don't understand is the extreme desire of Einstein, and relativists, to make everything in an inertial frame of reference relative. Their desire is so strong, they would even attempt to change the physical properties of space to fit their concept, and to even introduce a new physical property into physics (time). I must admit, if everything in an inertial frame of reference was relative that would be cool. But some people need to be reminded that science is not the pursuit of "coolness". For example, why can't the speed of light be tied to an absolute property instead of a relative frame of reference? Maybe the speed of light is tied to gravitational fields, or a type of aether that dav57 is suggesting. Let's not forget that the omnidirectional speed of light has only been found to be invariant on the surface of the Earth. If the speed of light is tied to a field or medium that is geocentric, then to assume that the speed of light in all inertial frames of reference is invariable based on measurements done on the surface of the Earth is just plain stupid. Finally, let me also say that many physical equations have been developed based on measurements that were done in stationairy positions on the surface of the Earth. If light, electric, or magnetic fields have ties to fields or mediums that are geocentric, then many of these equations are not universal, but are only a subset of a larger group of still unkown equations.