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<blockquote data-quote="freyar" data-source="post: 6750790" data-attributes="member: 40227">Re: your first question, I agree whole-heartedly with Umbran's answer.&nbsp; Regarding your second, the answer is yes, there is an analog of Hawking radiation for cosmological horizons.&nbsp; For example, in the very far future, it may be that our universe looks like a spacetime that's empty except for a cosmological constant.&nbsp; If you were sitting in such a universe, there is a distance beyond which you can never see, which is a horizon (for you) much like the horizon of a black hole.&nbsp; And you would indeed detect Hawking radiation from that horizon.&nbsp; There are some subtle differences in comparison to the black hole, and this type of universe is actually a lot less well-understood than a black hole is, but there are some definite similarities.I should say that this isn't something we see in our universe.&nbsp; Specifically, if we look far away, we can see the opaque age of the universe in the form of the cosmic microwave background as closer (in time, really) than the horizon distance.&nbsp; The universe will have to get a lot older before we can't see the CMB.</blockquote>

[QUOTE="freyar, post: 6750790, member: 40227"] Re: your first question, I agree whole-heartedly with Umbran's answer. Regarding your second, the answer is yes, there is an analog of Hawking radiation for cosmological horizons. For example, in the very far future, it may be that our universe looks like a spacetime that's empty except for a cosmological constant. If you were sitting in such a universe, there is a distance beyond which you can never see, which is a horizon (for you) much like the horizon of a black hole. And you would indeed detect Hawking radiation from that horizon. There are some subtle differences in comparison to the black hole, and this type of universe is actually a lot less well-understood than a black hole is, but there are some definite similarities. I should say that this isn't something we see in our universe. Specifically, if we look far away, we can see the opaque age of the universe in the form of the cosmic microwave background as closer (in time, really) than the horizon distance. The universe will have to get a lot older before we can't see the CMB. [/QUOTE]

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