Yes that's part of relativity and does not have anything to do with this. If he knows what we know he will know that everything is made of atoms, that the big ball of burning gas in the sky is a star, and all the stars in the sky are the same thing as his star and so on. The universe changes over time just not very quickly by our standards. In the majority of the time it's been around everything is still made out of atoms and stars and everything else so it's not like he will see anything that resembles something completely different from what we see.
