320 Are the Androids Dreaming Yet?

320 Are the Androids Dreaming Yet? Wave Interference have interference you sometimes get constructive interference — the double crest or trough — and sometimes destructive interference — the crest and trough canceling each other. The reason we don’t see this effect in every reflection is because of imperfection. Windows are not perfectly flat and light is multicolored, so the effect is hard to see. But it is definitely there, and if you look really hard at a reflection in a window, you can sometimes see it at the boundary of sharp objects. The effect is very clear in the next picture which has been set up with two flat pieces of glass resting against each other. There is a tiny air gap between them. It is also commonly seen on puddles in cities. In this case the puddle usually has a slight film of oil on it. Unlike glass, puddles are perfectly flat thanks to gravity, but the oil film is thick in the center and thin at the edges. The light reflecting off a puddle will show a rainbow of colors. This is because each color is giving us a pattern of light and dark. If you look at the same puddle at night in a yellow streetlight, you will just see a monochrome pattern of light and dark. Look at the picture of waves on a pond. The patterns of light and dark are usually explained by imagining the photons interfere with each other. This explanation is insufficient. Imagine for a moment you can see as well as a frog, and perceive one photon at a time. One moonless night just one photon comes to the two glass surfaces and reflects. What happens? HOUSE_OVERSIGHT_016010