On Fri, Jan 26, 2018 at 3:58 PM, <mix...@bigpond.com> wrote: Below: The conversion of matter into energy causes spacetime, and thus the > universe, to expand, since light has inertial but no gravitational mass.
Note that this sets up the weird situation of photons being influenced by gravity (e.g., gravitational lensing, the Schwarzschild radius of a black hole), but not having a reciprocal influence in return. Eric
