Spacetime invariants similar to a discussion where the answers pre- date the questions, as the question is seen nowhere. SRT allows for nothing to be faster than the speed of light, but if it is, it occurs on the causality boundary, such as a photon and its inscrutable life. Distance and time dilations occur in SRT, so faster than light equations seem impossible as light itself and spacetime become invariants. The photon is not sad. The attempt to vilify it shows an area of silence that all good reporting flocks to. 😶