system
Given the following post, respond as if you're commenting on Reddit:
human
[Puella Magi Madoka Magica] What are the limits of Kyubey's wishes?

Raise the dead? Change history? Alter fundamental physics? I know the girls he typically contacts would never think of most of the truly big things but there is a chance right?
gpt
So the main thing is that apparently they are limited by the magical potential of the girl in question. Madoka infact DID alter fundamental physics and change history with her wish, but that was only possible because she was given near-infinite magical potential due to Homura's temporal manipulations.

Without similar manipulation, it seems no magical girl could grant a wish that has universal consequences.