almosthere

As far as I know: Time is the interval between any two events. So you can use gravity to measure time, I could define a unit of time of 1 theta to be the time it takes for an object to fall from 3 meters to the ground. My problem with theta however is that the gravitational force itself changes with elevation, so i'd have problems with measurements, since the time for the object to land will vary between sea level and a mountain. The same problem exists with rotation around the earth, its not constant, so folks use atomic clocks that measure frequencies of microwave radiation emitted by electrons to determine time units. Another problem you are going to run into is the fact that things can't be explained via gravity at the atomic level. It seems to be a world of its own, with its own rules guiding how electrons move around the nucleus and stuff. Which basically messes with the fact that for something to be fundamental, it needs to be observed everywhere. electrons have space, mass, time and energy, but they don't demonstrate gravity, and electrical stuff generally doesn't follow any gravitational rules. Space as we knew it a hundred years ago was just distance-based. By space I don't mean just blackness above earth, but what we all live in. If all of it was black, measuring any distance is of no use, but unfortunately there's a few planets in it, and worse, a species thats curious about this which figured out ways to conveniently measure distance by creating 3-dimensional geometry. If that wasn't enough trouble, in walks Einstein who starts figuring out this mischevious dude called light. The problem with light was that it was having trouble obeying laws of relative velocity. if train is moving at you at 100 mph and you were moving towards it at 100 mph, you'd measure the speed of the train as 200 mph. But, light was having none of this and moving at 300,000 km per second regardless. It didn't matter if you were moving towards it at 100,000 km per second. you would still promptly record 300,000 km per second. Something was messing with speed = distance/time in the case of light. since the speed was constant at 300,000 km per second and distance travelled always the same, Einstein figured that time must be the culprit and worked out that time stands still at the speed of light. Until they figured this out, satellite communication was getting messed up because nobody imagined that light was a disobedient dude. Thats when we decided to upgrade the universe to 4 dimensions...3 dimensions of distance in each direction and time, because for objects that move faster, time moves slower. Time travel is speculated at speeds above speed of light, but thats pure guess work and hasn't been observed or proved at all.