Thread: process reversal phenomenon

Consider a series of mathematical functions yielding some result. To get the same result in same number of steps by disturbing the previous sequence of mathematical functions or following completely new math functions to arrive at the same result in same number of steps. This is possible. For example if a star is born then many physics processes go into it. But when a star dies the processes involved are completely different. if we consider such an isolated star then its energy and mass will be conserved. in the end some things are conserved while some things change.

I WANT TO KNOW WHETHER SUCH PROCESSES EXISTS.