Why does it have to be a cell phone that required cell towers?
It doesn't, it could be a magic time phone, but it can't be a
cell phone. If we're going to postulate undiscovered technology, maybe she's talking to her voice-operated transmutation device.
But hey, Occams's razor, amiright?
If there is one thing that history has taught us is that predictors of limits on human ingenuity are always doomed to fail. After all, it was laughable that I would be using a computing device thinner than my folder while the most advance computers ran on vacuum tubes.
Yeah, I know. Have you read James Blish's
Cities In Flight series? They can make cities fly through the galaxy with antigravity, they have a force-field that keeps the air in ... and they use slide-rules.
Edited by Dr Adequate, : No reason given.
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