Electron–Positron Annihilation

1 – 10 s · Radiation Era

Temperature (K): 5000000000
When: 1 – 10 s
Redshift: —
Era: Radiation Era
Seconds After Big Bang: 10

What Happened

Electrons and positrons annihilate, leaving only the one-in-a-billion excess of matter and heating the photons relative to the neutrinos that had already left.

Researchers

Paul Dirac

Equations

Planck–Einstein Relation Mass–Energy Equivalence

Theories

Quantum Electrodynamics Big Bang Cosmology

Referenced by

equation

Mass–Energy Equivalence Planck–Einstein Relation

researcher

Paul Dirac

theory

Big Bang Cosmology Quantum Electrodynamics

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From the Cosmic Timeline database in Notion, last edited 2026-08-16. This page is the row, rendered by the build; nothing on it is written by hand.