I have been wondering why the universe should behave in such a way. There is no obvious reason why gravity or speed should change the rate you travel through time or the relative distances, 1 second should be 1 second and 1 metre 1 metre whatever the strength of gravity or speed. The only reason I can come up with is that it changes the geometry of spacetime from one form to another, it should be possible to make say spherical spactime appear square. If time can slow down in one direction then it must speed up in the other. At c is it mass or space that becomes infinite? I ask this because if space becomes infinite and time 0 at c then at a singularity i.e in a Black Hole the opposite should happen as speed becomes 0. This would give at one end infinite space being crossed in 0 time and at the other infinite time taken to cross 0 space and everything inbetween being the universe as we see it. Is it possible that gravity and time are the same thing, something travelling in time slightly faster than something else would appear as an attraction between the 2 things the greater the time difference the greater the attraction would seem.