Re: What is TIME exactly?
While magnetism has never been unified with gravity, simple observation tells us that magnetism alone has no effect of the passage of time. We now can measure the passage of time in incredibly small increments, and in fact have genernerated magnetice feilds far grater than that and noticed no time effect would tend to mean that even if there is a connection, it must be incredibly small.
I did have one thought about your infinite speed of light idea. While we know that the speed of light photons is not infinite, for massive objects it effectively is because you simply cannot attain that velocity. So I apologise because you are quite correct in that regard.
If you are not part of the solution, you are part of the precipitate.