There is a race track near my town. One driver, racing for team ISS, stays always on the outside edge of the race track, and the other, racing for team Earth, stays always on the inside edge of the race track.
Using their odometers they each measure the length of 100 billion laps around the same track
. One obtains a length of 250 billion km and the other 500 billion km.
So who is wrong and who is right? I mean, do you believe that the track can be both 250 billion km and also 500 billion km? It doesn't sound logical - and hence hard to buy.
Therefore, the laws of physics must clearly be different on the inside of the track and the outside.