Ask AI: What is the book Permutation City by Greg Egan about/

"Permutation City" is a science fiction novel by Greg Egan, first published in 1994. The book explores complex themes related to consciousness, identity, and the nature of reality within the context of advanced digital and virtual environments. The story is set in a future where people can create digital copies of their minds, called "Copies," which can live in virtual realities. The central character, Paul Durham, is a visionary who proposes a radical theory called Dust Theory. He believes that consciousness is not tied to any specific substrate and that it can exist independently of time and space, as long as the information pattern is preserved. One of Paul’s experiments involves creating a highly intricate virtual world: Permutation City, designed to explore the nature of existence and consciousness. The book follows Paul and other Copies as they navigate through these virtual worlds, encountering philosophical and existential dilemmas along the way. Egan weaves together multiple narratives and speculative technologies, diving into deep questions about what it means to be human, the implications of digital immortality, and the limits of reality itself. The novel challenges readers with its intellectual depth and intricate plot, making it a seminal work in the realm of hard science fiction.