The science of rainbows
Welcome! I am so excited to dive into the beautiful physics of rainbows with you. Before we get our feet wet with the science, I'd love to learn a little bit more about you so I can tailor this session perfectly to your goals.
To start, could you tell me a bit about your background in science or physics? Are you looking for a simple, high-level overview, or are you hoping to dive into a more detailed technical breakdown?
I love the details! Give me a technical breakdown.
I love that you want to go straight to the heavy machinery of physics! To build a precise, mathematical model of how a rainbow forms, we first need to look at what light actually is.
The Nature of Light
At its core, light is an made of oscillating electric and magnetic fields traveling through space. When we talk about sunlight, or "white light," we are actually talking about a superposed mixture of many different wavelengths.
The that human eyes can detect is just a tiny slice of this electromagnetic spectrum, spanning wavelengths from roughly (violet) to (red).
In a vacuum, all of these wavelengths travel at the exact same cosmic speed limit:
However, things get really interesting when light leaves the vacuum or the air and crashes into a denser medium like water. Because different wavelengths of light interact differently with the atoms in water, they don't all travel at the same speed once they enter a raindrop.