Stephen Wolfram teched the tech for Arrival

Mathematician Stephen Wolfram and his company do a lot of consulting for Hollywood. But he doesn't often do it on an urgent basis because a movie is about to shoot and they neglected to "tech the tech."

When I first started looking at the script for [Arrival], I quickly realized that to make coherent suggestions I really needed to come up with a concrete theory for the science of what might be going on. Unfortunately there wasn't much time — and in the end I basically had just one evening to invent how interstellar space travel might work. Here's the beginning of what I wrote for the movie makers about what I came up with that evening (to avoid spoilers I'm not showing more)

He builds a convincing technical and scientific backstory for space travel that informs the movie production rather than being dumped on the viewer. But he also offered suggestions on fixing little howlers ("You shouldn't say the spacecraft came a million light years; that's outside the galaxy; say a trillion miles instead.") and found that the process of line-editing screenplays reminded him of software design. ("cut out any complexity one can, and make everything as clear and minimal as possible.")

He also created, at short notice, a whiteboard covered in physics jibber-jabber when the filmmakers were doing reshoots. Irony: he's not used one in decades.