---
name: light
slug: light
type: fundamental_phenomenon
status: unstable
version: 0.0.666-alpha
released: "-13,800,000,000 years (approximate, contested)"
maintainer: "@universe (unresponsive)"
dependencies:
  - photons
  - Maxwell's equations
  - an observer (optional but it keeps asking)
  - the_absence_of_light
license: GPL (Geometry of Perceptual Limitation)
tags:
  - electromagnetic
  - particle
  - wave
  - yes_both
  - haunted
  - visibility
  - speed_limit_enforcer
---

light

What it actually is

A disturbance in the electromagnetic field that travels at the maximum speed the universe permits, while somehow also being a particle, while somehow also being neither until you look.

How it works

Photons are emitted. They travel. They arrive. Somewhere in the gap between emission and arrival, reality has to decide what it was doing. Light does not wait for this decision. Light does not wait for anything.

The mechanism, briefly:

Charged particle accelerates
Electromagnetic field ripples outward
The ripple has no mass, so it hits the universal speed cap: 299,792,458 m/s
It arrives at your eye or your detector or a wall
You call it light. It does not care what you call it.

"I set up the double-slit experiment and now I'm pretty sure it set up me." — anonymous physicist, recorded 1927, still unresolved

Features

Feature	Status	Notes
Illumination	`STABLE`	works as intended since 380,000 years post-Big Bang
Wave behavior	`UNSTABLE`	collapses when observed
Particle behavior	`UNSTABLE`	appears when observed
Color	`BETA`	frequencies interpreted by wetware, results vary
Speed enforcement	`RUNNING`	no exceptions logged, ever
Warmth	`LEGACY`	inherited from fire, still emotionally significant

Known bugs

Superposition not resolving cleanly. Light exists in multiple states simultaneously until measurement. This is not a bug the maintainer will fix. This is load-bearing.
Horizon problem. Regions of the universe share the same light-temperature that could not have exchanged light. This implies coordination. No ticket has been filed. Everyone is afraid to file the ticket.
Shadows. Light should fill everything. It does not. Geometry is intervening. Geometry has always been intervening.
The speed of light in a vacuum is constant but the vacuum is

Error codes

ERR_OBSERVER_COLLAPSED_WAVEFUNCTION    // you looked
ERR_PHOTON_ARRIVED_BEFORE_SOURCE_KNOWN // entanglement adjacent, do not debug
ERR_DARKNESS_NOT_ABSENCE               // darkness has its own spec, stop treating it as null
ERR_SPECTRUM_EXCEEDS_WETWARE           // user eye cannot render. data exists. user cannot have it.
ERR_REDSHIFT_IRREVERSIBLE              // that galaxy is gone. the light is a letter from someone who moved.

Edge cases

Light passing through glass slows down. It speeds back up on exit. No explanation has satisfied everyone.
At the event horizon of a black hole, light is the last thing to fail.
Bioluminescence exists: living things generating light from chemistry. This should not be possible. It is fine.
In the first 380,000 years of the universe, light could not travel. It was trapped in plasma. When it finally escaped, we call that moment the cosmic microwave background. It is still arriving. You are being arrived at right now.

FAQ

Q: Is light a wave or a particle? A: Yes.

Q: What is light made of? A: Photons, which are excitations of the electromagnetic field, which is a mathematical object that happens to be real, which raises questions nobody has answered.

Q: Why does light feel good? A: Serotonin. Also something older than serotonin. The spec for that is not ready.

Q: What is on the other side of darkness? A: More light. Probably. File a bug if not.

drafting spec…