Why can nothing go faster than light?
Nothing outruns light because influence spreads by reading, and every read has a maximum reach. Each record in the world writes its next value after reading the records within a fixed reach of it, round by round. After five rounds an event's influence has got at most five reaches away, and everything closer than that can be reached. As the records get finer, that region of influence closes onto a single cone, the light cone, whose speed is one reach per round. Quoted in meters per second, it is the speed of light. Light carries nothing extra and moves at the full limit. Everything with mass carries a second part that has to be re-asserted every round or the thing stops being there, and paying for that holds it below the limit.
Also in Chapter 28: What Is a Particle, What Is a Wave, and Why Does It Look Like Both?.
This answer comes from OPH, Observer Patch Holography. OPH is a rigorous, consistent and complete description of the unified, self-creating computational Universe we inhabit. Its consistency is machine-checked: the fixed point at its core is constructed explicitly, and a theory with a model contains no contradiction.
To understand OPH and check every step yourself, start with the free book Reverse Engineering Reality. It builds the theory from the ground up, and the OPH Notebook answers your questions while you read.
read the free bookask the notebookor ask sage:read chapter 17: Why Is There a Speed Limit?watch a universe make its own particles