My mom, has of late, become more and more interested in the intersection between quantum mechanics, astrophysics and faith. She is fascinated, though like me, relatively ill-informed about the physics portion of the discussion. Nearly finished with her M.div, she's certainly more informed about the spirtual side of the discussion than I am, so essentially it's the blind leading the near sighted. I told her about the book I read earlier this year, Brian Greene's Fabric of the Cosmos. It's a really tremendous read, and one that even a dullard like me can follow. The example that has stuck with me, and which I can still mostly recall deals with the nature of time as it relates to motion. I explained it to my mom, but I wanted to check with my readers (especially those with more information on the matters) to make sure I wasn't misleading her.
I explained that objects are moving either through space (speed) or time (time) or through both. The total movement of all objects is the same, it is the allocation, or vector that they travel that is different. For instance an object that is completely stationary is travelling almost entirely through time. Its lack of motion through space means that all of its energy of motion is devoted to moving through time. Similarly when an object moves closer and closer to the speed of light it is moving less and less rapidly through time. Meaning that the faster an object moves (through space) the slower it moves through time. I think I tried to explain this notion on this blog before, but I'm not sure if I got it right, or was as clear as I should have been.
Does this mean that at the speed of light there is no time? It seems like that is the case. So light does not exist within time? What are the practical/theoretical implications of something that fails to exist within time?