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If a person on Earth today is looking at a star, say, 10 billion light years away, is it possible that some of the atoms he is looking at will eventually go on to make him?

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If the atoms travel at half the speed of light, wouldn't you have to live another 10 billion years for them to reach you? –  RedGrittyBrick Jan 19 '13 at 22:42
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If you like this question you may also enjoy reading this Phys.SE post. –  Qmechanic Jan 20 '13 at 6:26
    
As pointed out, the atoms of that star would have had to travel faster than light to reach earth in time to form you. But if you really want to look back in time at yourself, a mirror will do the trick. And the farther away you stand from it, the further back in time you will see yourself. :) –  Wouter Jan 20 '13 at 10:21
    
Thanks team! Wouldn't it be incredible to 'see' the reflected light rays from Earth's history today?? We could point our cameras at a big mirror somewhere in the universe and 'see' the Library of Alexandria, the dinosaurs etc etc!! –  wideangle123 Jan 20 '13 at 10:56
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I don't think so because the atoms would have had to travel faster than the speed of light to get to you (to form you) before the light they reflected got to you, and from what I understand, nothing travels faster than light.

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Hi T-Fox. I don't provide contradiction to your quote: "Nothing travels faster than light". Actually, objects with zero mass, can travel at $c$. Whilst on the other hand, objects having negative mass, can travel faster than light. By saying mass, I really meant rest mass. The problem is, we haven't observed any superluminal objects yet and we won't. Maybe that's the reason I didn't argue with your quote ;-) –  Waffle's Crazy Peanut Jan 20 '13 at 5:09
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