Sherab wrote:When ignorance disappear, sankhara disappear; when sankhara disappear, vinnana disappear as so on. In other words, the whole PS chain disappear. If the whole PS chain disappear, what have we got left?
Are you asking in reference to an arahant who is still alive or who has died his last death? An arahant who is still alive still experiences some of the PS chain. For example, contact still leads to feeling. Food will still taste good or bad or neither good nor bad. But feeling will no longer lead to craving. For example, the arahant will neither crave good tasting food nor resist bad tasting food.
To put it another way, there is no separate realm. An arahant lives in the same world as the rest of us. His senses still function, he still eats, and sleeps, and thinks, and eventually he dies.
The jump is that the realm that sentient beings ("impure" beings) inhabit are "created" by their ... karma. "Pure" beings therefore do not share the same collective karma to inhabit in the same realm as the "impure" beings.
An arahant continues to live in this impure realm as a result of past karma. Some past karma resulted in him being born. Once born, one grows, older, sicker, and eventually dies. Arahantship does not change this. Once the arahant eventually dies, however, there is no condition for him to be born again.
Now if you are asking about an arahant after death... well the Buddha said quite explicitly that this is something beyond talking about.