Hello everyone, I was doing my Physics homework and a question arose from it: if a mass affects time there is a difference in the time measured near different masses. However if there was no mass at all? Let's pretend this is possible just for theoretical purposes, a perfectly flat space-time. In this situation time would not pass at all. So how can light travel through such regions? (I know there is not such a thing in the Universe but intergalactical space may have very little space-time distortion.) Just to confirm if my understanding is correct: time would pass slower near the Sun than near the Earth? (imagine they are both static, they do not have either translation or rotation) Thank you very much!