Comment by janandonly
4 hours ago
I think the old SciFi classic "Zone of Thought" and the other book which name escapes me now explorer this idea, although not 5Km/h.
To stop a 'blight' in the universe, some natural laws have to be changed wherever it starts to spread, is the story premise if memory serves me.
The third volume of « Three body problem » and its fan-written and author-approved sequel deal with those local physical constants changes !
"A Fire Upon the Deep" and "a Deepness in the Sky" by Vernor Vinge
Deepness in the Sky "programmer-archaeologist" will never come to pass because of LLMs :(
The Forever War series changes the speed of light at the end to mess with the mortals, not to prevent any calamity however.