Q: Is there any instance or theory where you would use a negative number for time?
A: In Classical Physics (Newton’s Physics), time only goes one way, always forward. Thus, time and time change are always positive. However, in Einstein’s Relativity theory, time can go backward in certain extreme cases. Wiki or Google “Relativity” if you want to know more. Or check out this interesting video: https://www.youtube.com/watch?v=ttZCKAMpcAo
