Sophon is an intelligent microscopic particle made by three body humans unfolding protons in two dimensions and etching circuits.

In Trisolarans III: Eternal Death, he possesses a biomimetic body created by humans in the solar system. Before the Trisolarans galaxy was struck, it was controlled by the Trisolarans world. After the destruction of the Trisolarans galaxy, Zhizi self immolated during a tea ceremony conversation.