ie. that particle accelerator type gizmo we saw a glimpse of earlier in the season. there's some theories floating around that it's not specifically time travel related, that it's more along the lines of a simulacra/matrix type situation (their world isn't all the way real).
Esmail pretty much ruled out introducing time travel at this point in the series, and other than paralleling real world billionaires ambitions to transcend the restraints of humanity, it's lookin like there's a sneaky sci fi angle/long game (seeded via WR's comments going back to season 1).

Angela may be impressionable at this point but she's not delusional. she had to have seen or heard something profound to be where she is now. or maybe it's all bullshit and she's in on a long con.

V.