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Some Observers Perceive the Universe To Be Much Younger Than We Do
StartsWithABang writes: It's been 13.8 billion years since the Big Bang for us, and when we look out at a distant object in the Universe, we're seeing it as it was in the past. Its age — as it appears — is determined only by how long the light took for it to travel from that object to our eyes, but to someone living there, it will also appear that the Universe is 13.8 billion years old. But it is actually possible for an observer living on another planet, star or galaxy to perceive that significantly less time has passed since the Big Bang, so long as they were moving close to the speed of light relative to the CMB. Paradoxically, if they slowed their speed, they'd find that they themselves were very young, but living in a 13.8 billion year-old Universe.
Presuming they were able to detect the CMB - which would NOT look the same in all directions - and "correctly" identify it (i.e., presuming that that's what we've done), they would then also be able to calculate their own relative movement, and correct for it. So they'd reach pretty much the same answer that we do.
Yes, we do have motion relative to the CMB, and this causes one side of the CMB sky to appear hotter than the other. Here's an APOD describing it. So everything discussed in the article already happens to us, here on Earth, but in a much less significant way.
Unfortunately I'm not at all sure that he actually got it right though because I think he has forgotten about General Relativity. He treats the entire universe as if it were a single object at rest in the CMB frame. However it isn't: it consists of many constituent components all with their own individual rest frames.
As we look further away from us galaxies are travelling closer and closer to the speed of light and so appear "slowed down" by time dilation due to the expansion of space itself which you need general relativity to account for. All that travelling close to the speed of light should do is shift which galaxies are slowed by time dilation and which are in almost the same frame and so not slowed. Hence you would see effectively exactly what we see now but it will be different galaxies which are in view because you are in a different inertial frame.
Hence I am not at all sure that he got it right. Certainly I'd like to hear it from a cosmologist before I believe it since GR is far more complex than SR and it is easy to get stung applying SR to a situation which requires GR and hence my cautiousness about whether he is wrong since I'm not a cosmologist. This would far from the first thing that he has got wrong...but it would be the first truly spectacular failure.
I'm a creationist, a Christian. I believe the universe is somewhere around 13.5 billion years old. A true reading of Jewish and Christian bibles will reveal this to be the truth. I'm not here to debate the existence of God, rather to say that as a Christian, God is the one who gave us science. Judaism/Christianity and science are partners not or/or.