LMR-045 · Light
Photon
A massless messenger that always travels at the universe's speed limit.
§ A first look
§ Depths
Six ways into the same idea — from bedtime story to chalkboard. No order required.
L1 · Crayon
Told like a bedtime story.
For a curious 10-year-old. No jargon. Just a picture in your head.
Light isn't a smooth continuous stream like water from a tap. If you turn a light source down lower and lower, eventually you'll find that the light comes out in tiny separate dots — one dot, then another, like raindrops you can almost count. Each one of those dots is a photon. A photon has zero weight, always travels at the very fastest speed there is, and never gets tired. When you see anything at all, photons are landing in your eyes. You are constantly being gently rained on by light.
§ Strange but true
- 01A photon doesn't experience time. Its trip from a distant quasar to your eye is, to it, instantaneous.
- 02Photons are their own antiparticle. Mirror one and you get itself back.
- 03Light always travels at the same speed — for everyone, in every direction, no matter how fast they're moving. This is the rule the universe is built on.
§ From the field journal
Photon
"A massless messenger that always travels at the universe's speed limit."
— observed, sketched, not yet fully understood.
§ Nearby