AST-703intermediate

Discovery & Blackbody Spectrum of the CMB: Physical Mechanisms

The cosmic microwave background, or CMB, is relic thermal radiation released when the universe became transparent roughly 380,000 years after the hot early phase began. The CMB anchors measurements of cosmic age, geometry, matter density, primordial fluctuations, and the physics of recombination.

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Discovery & Blackbody Spectrum of the CMB: Physical Mechanisms

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AST-702Discovery & Blackbody Spectrum of the CMB: Structures & Vocabulary→

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AST-704Discovery & Blackbody Spectrum of the CMB: Observation, Measurement & Evidence→

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The cosmic microwave background, or CMB, is relic thermal radiation released when the universe became transparent roughly 380,000 years after the hot early phase began.

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Before recombination, free electrons scattered photons frequently, coupling radiation to ionized matter.

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