That's the thing. Because light isn't just a wave, ether has been thrown out of the equation. Before 1905 scientists had a hard time explaining how can light, as a wave, travel through space, since a wave needs some sort of substance to propagate through. So, physicists called this hypothetical substance ether which filled the entire universe. A photon though, can travel through vacuum just fine so after Einstein's relativity paper, ether was gone from physics.

The wave-qualities of light is now perceived differently than it did at those times. It's only a mathematical wave, which gives us the ability to predict the motion of those photons, and any other microscopic particle, with some uncertainty. Another way to predict the motion of particles, as shown with Young's double slit experiment, is to calculate two different instances of the very same atom that collide with each other, predicting its final destination. These two instances are located at two different places at the same time.