I've been thinking about this more. And I think that without matter we would still have space and time. Matter is just something that affects spacetime. But.. thinking about the three dimensions of space, would they still be existent if there were no matter? I am thinking that they would, that...
If there was no matter or energy we wouldn't have a universe... but I suppose all that there would be would be space... and since space and time are the same I guess there would still be time. But I think it is common for people to think that light is time. Which I don't agree with. I think...
Since space and time are considered one thing due to Einstien's research... Would time be considered the movement of matter through space? Or possibly that time is created by extremely massive objects such as the sun? I'm not sure.