Similar to Seveneves by the theme of natural disaster catalyzing tremendous societal upheaval.

"Why can't you stay inside your citadels of infinite blandness, and leave us in peace? We humans are fallen creatures; we'll never come crawling on our bellies into your ersatz Garden of Eden. I tell you this: there will always be flesh, there will always be sin, there will always be dreams and madness, war and famine, torture and slavery."

Introdus is cool, it turns people into a crystalline orb; a snapshot of their consciousness to be reified elsewhere, kind of like the _Jaunt):

Inoshiro stooped down and picked up the end product: a crystalline sphere, a molecular memory containing a snapshot of everything Orlando had been.

Wormhole math and the way that Egan is able to describe higher-dimensional spaces through narrative prose in a way that doesn't sound like total poppycock is so enjoyable. Some of the best hard sci-fi out there.

Interesting thought experiment a la Nightfall wherein the copy of Paolo and Elena arrive at Orpheus had different rules in mind for the copies of themselves that were sent out

Flirts with the idea/existential question of where does the computation happen in nature?

Nice Shamyalan twist/prestige of the diaspora members getting diaspora'd themelves. Everything else from their home life, and the significance of been diluted in the scale of their journey

And above all else, that which elevates this book above run-of-the-mill is the use of the ultra-futuristic setting to explore transcendental questions of the human condition. In this respect, I think Egan is unparalleled in his breadth and depth:

Ve whispered to Francesca, dismayed, "I thought religion was long gone, even among the statics."

"God is dead, but the platitudes linger." Yatima couldn't bring verself to ask whether torture and slavery also lingered, but Francesca seemed to read vis face, and added, "Including a lot of confused rhetoric about free will. Most statics aren't violent, but they view the possibility of atrocities as essential for virtue—what philosophers call `the Clockwork Orange fallacy.' So in their eyes, autonomy makes the polises a kind of amoral Hell, masquerading as Eden."

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