I have often thought about it as such, and I have likened light to be the medium of energy and information transfer in our Universe. I would think gravity and forces were caused by light information travelling to particles, causing them to move accordingly.
The slowest part of any game engine would usually be the Physics. Because it has to compute velocities first and then positions next, for a variety of objects. Also, fast moving or large objects are often problem children for our Universe, because the simulation timestep has to be be chosen wisely to avoid glitches, intersections and the like. Also, since there has to be coherence across all the chosen objects when it comes to observability of each other, there must be a co-ordination for all of them.
Which means all parallel computations are eventually going to be run serially, at the end of the day. Which makes the Universe a god of simulation in time.