Not sure how many know this...maybe by now it is common knowledge, but light can be a photon particle or a wave depending on the process of observation. My first info on this came in 1982 while reading the "Tao of Physics" by Fritjof Capra...an EXCELLENT book for those interested in physics and theory.
My second reading on this came in "Dancing WuLi Masters" by Gary Zukav..In this book there is an example of how to create the wave-particle experiment. I did it and it was very much fun and certainly opened some doors to quantum!
Bob