I’m very late to the Greg Egan party. I don’t know why – just never picked up an Egan book and read it. Diaspora was extraordinarily ambitious and yet Egan managed to keep an inherently sprawling idea focused and on track without compromising any of the ideas.
Diaspora plunges into the deep end: the science that is fictionalised is the science of consciousness, pure mathematics (especially topology), and fundamental physics but the story also takes on more humanist questions of survival, what it means to be human and also questions of identity and society.
The thread of the novel follows Yatima, a person who is ‘born’ in a ‘polis’: that is a human intelligence that exists purely as software in a giant virtual community of such people – most descended from actual people. The opening chapter, describing the formation of their mind (i.e. their birth) can be read in full here: http://www.gregegan.net/DIASPORA/01/Orphanogenesis.html
It’s head first into a transhuman future. Most characters are polis citizens: intelligent software living virtual lives but with human emotions, desires and ambitions. Each polis has its own culture and an important aspect of that culture is the attitude towards reality. Some citizens are inclined towards heavy interaction with actual reality, engaging with what is going on with the rest of humanity in various ways. Others are solipsistic, withdrawn into virtuality and moulding alternative realities of their own.
The citizenry are not the only descendants of humanity though. People exist in two other major groupings.
Gleisners, like citizens, are software intelligences but unlike citizens they are embodied and interact with reality in robot bodies. Obsessed with space exploration, the gleisners are culturally different from the citizens but are in active communication with them.
Fleshers, are biological humans and represent the most diverse group. Exuberant fleshers have genetically modified themselves in myriad ways to the extent that the capacity for common language between fleshers has become difficult because the sense-experiences of different groups may be radically different. Statics are humans with little or not modifications, who are seeking to retain humanity as it was.
The obvious choice of point-of-view for this setting would be to focus on a static as a reader stand-in and explore the world of post-humanity from that perspective. Egan avoids that, and chooses a story and focus centred around the citizenry.
Having said that, the main plot of the story really only begins when two citizens (Yatima and Inoshiro) download themselves into two abandoned gleisner bodies and attempt to visit the flesher community of Atlanta. This visit, establishes relationships based on a common humanity which becomes vital as the story progresses and all three kinds of humanity face an astronomical disaster.
Dimensional realities hidden in fundamental particles, competing theories of wormhole generation, software clones of people designed to communicate with crab-like being living in different orders of reality. It’s a kind of Alice in Wonderland rush of ideas but played straight as ‘hard’ science fiction.
Loved it. I’ll need to re-read it and bit more slowly soon, as I’m sure I missed bits.