Glossary · term

Photon

Quantum

Domain
Quantum

Definition

The quantum of the electromagnetic field: massless, always moving at c, carrying energy hf. Light behaves as a wave right up until you count the arrivals one at a time.

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From the Glossary database in Notion, last edited 2026-08-17. This page is the row, rendered by the build; nothing on it is written by hand.