In the early days of lasers, experimenters used to mirror both ends of a ruby rod with one end slightly less mirrored than the other. Then the chromium atoms were stimulated to higher levels of excitation releasing more and more photons (light waves). As the light was reflected back and forth, new waves joined in and were therefor forced to pack tighter and thus "cohere": line up hill to hill and valley to valley thus increasing the packing density (intensity)of the beam. At a point, the intensity became such that the beam broke through the less mirrored end of the ruby rod in a coherent beam. That's the lase.
1. Higher Intensity does not necessarily equate to increased Velocity.
2. Neither reflection nor refraction increases velocity. It decreases it. Whatever you read "somewhere" was either wrong or you misread it.
3. Going to NIST will do you no good until you spend some time with Physics 101.
4. Reflecting light from mirrored surfaces is only one of many ways used in measuring the speed of light, all of which give the same value. Many methods predate NIST by centuries and are in agreement to within a few m/s. All of which prove 136,646 miles per second to be incorrect.
