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Mr Davis 97
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I am having conceptual issues about what the CMB actually is. I read that it is the remnant radiation at the moment of recombination roughly 380,000 years after the Big Bang. But what about this statement implies that we would be able to observe this radiation today? To put it naively, when I look up into the night sky, where exactly is this radiation coming from? As a parallel, when I see a star I know that I am seeing the light that it emitted possibly millions of years ago relative to me. How can I really make a parallel statement when it comes to the CMB radiation, when looking out into the void of deep space, when at the time that radiation was present everywhere in this universe at the same time? I guess my main concern is how radiation encompassing the entire universe changes over time in an expanding universe. Also, if at the time 380,000 years after the big bang, this light was free to roam all over the universe, why can't it emitting from inside my house or a patch of land nearby? Why do have to look into deep space?