AST-687beginner

Particle Epochs of the Early Universe: Structures & Vocabulary

As the early universe expanded and cooled, the particle species and interactions in thermal equilibrium changed. Early particle epochs connect collider physics, dark-matter freeze-out models, neutrino cosmology, baryogenesis, and Big Bang nucleosynthesis.

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Particle Epochs of the Early Universe: Structures & Vocabulary

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AST-686Particle Epochs of the Early Universe: Foundations→

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AST-688Particle Epochs of the Early Universe: Physical Mechanisms→

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As the early universe expanded and cooled, the particle species and interactions in thermal equilibrium changed.

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Expansion reduces temperature and density, while interaction rates determine whether particle populations remain in equilibrium.

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Particle physics experiments constrain relevant reactions, while primordial abundances, the CMB, and the cosmic neutrino background predicted by the model encode consequences of early thermal history.