By definition, elementary particles can't be broken into smaller pieces. But in a new theoretical study published in Physical Review Letters, Johannes Skaar and colleagues have revealed what would happen if you tried anyway for a single photon. The answer is deeply strange: attempting to cut a photon in two wouldn't produce two smaller photons, but instead conjure an infinite number of them out of thin air.
If you flipped a mirror back and forth fast enough to “split a photon” you’d end up generating a bunch of photons due to the heat energy generated by the system anyway. I’m sure that’s not what they’re talking about but just imagine something oscillating that quickly.