- #1
Phys12
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- TL;DR Summary
- If CMB is the oldest light in the universe, then how is it that we potentially can never know something about the universe that emits light.
So, as I understand it, the photons from the microwave background were the result of photon decoupling. Now, if I remember correctly, because of the accelerated expansion of the universe, the diameter of the universe is not about 28 Gyr, but about 90 Gyr, the consequence of which is that there are objects that have accelerated faster than the speed of light and the light that was emitted by those objects will never reach us and so we will never be able to see that light. But how is it possible that we can see the oldest light in the universe (CMB), but never be able to see a younger light (emitted by some object) that was produced after the oldest light. Does my question make sense? If yes, what am I missing?
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