Final answer:
The Big Bang Theory posits that the universe began from a singularity and evolved over time. The Cosmic Microwave Background (CMB) is a result of the 'recombination' process, where protons and electrons combined to form neutral hydrogen atoms, subsequently releasing photons that we detect as the CMB today.
Step-by-step explanation:
The Big Bang Theory is a cosmological model that describes the universe's inception from a singularity and its subsequent evolution. The Cosmic Microwave Background (CMB) is radiation that fills the universe and can be detected in all directions. According to this theory, in the early stages of the universe, it was filled with a hot, dense plasma of protons, electrons, and photons. As the universe expanded, it cooled, and eventually, the protons and electrons combined to form neutral hydrogen atoms. During this process known as recombination, the photons were 'set free', and these photons are what we detect today as the CMB. It's a snapshot of the universe at the moment of recombination when neutral hydrogen was formed, which occurred about 380,000 years after the big bang.
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