You've Never Seen This

Go search online for pictures of bubbles and look at what colors are on the surface. For me, it's magenta, yellow, green sometimes, but never red. But it's a phenomenon that's kind of the opposite of rainbows. What I mean by that is that in bubbles, colors are removed. They are cancelled. And it all has to do with thin films, which is something that you learn about if you're taking physics and you get to wave interference. What's that? Well, there's this phenomenon that happens sometimes near a seashore. It's really cool. where a wave comes in and crashes on the shore and it can reflect back and travel backwards and then if it hits an incoming wave you get these monster waves when they collide. The monster wave happens because of something called wave interference where you can add up two waves and they combine for a bigger wave. So now the same thing can happen with light because light is a wave. So interference goes both ways. If you have a crest and a crest, two ups, then you add and you get a bigger up. I can't do it. or if you have a crest and a trough, an up and a down, then they add and they cancel out and you get zero. It can happen in sound waves, which is how you get noise cancelling headphones. And it can happen in light waves where the waves come together and cancel each other out. If you imagine shining two lights on a spot, they add and they look even brighter than if you have just one of the lights. But you can also shine two lights and get the spot to completely disappear. So the next step, this wave interference thing that can make light cancel. It's so cool. Can create colors from white light. So for certain thicknesses or certain angles, you get red canceled out or you get blue canceled out or yellow. So the only colors you can see in a bubble are the result of subtracting out one color. So you never get red because you would have to cancel out yellow, orange, green, blue, indigo, violet, all of the rest of the visible spectrum in order to see