[Oh, she is going to read into it, buster.

...Quietly.

And Evelyn would ask a certain physicist about wormholes, but he's been missing for a while, so the library is all she's left with.]

I wouldn't assume that - it seems to be based on who you are, rather than where and when. I've noticed that in many cases, people from like dimensions appear because someone else they know got here before them. I would postulate that the mechanics of this place revolve not simply around memories, but relationships.