Chronology of Time Split

If time is the only river, then on which stone in the river bed is "free will" hidden? Humanity has discovered a natural phenomenon called Time Rift. It proves that time is not a monolith, but a continuous medium with gaps, dislocations, and stress concentration points. Every major "collective historical memory" accumulates stress in the time dimension, and eventually tears out a window that can be briefly traveled. But "Time Crack" also proves another thing: there is causal corrosion in history, and it will repair itself. The more critical nodes are forcibly changed, the more stubbornly they will return to their original results. Humanity thus falls into the ultimate dilemma.