Reading Suggestions
 
Isaac Asimov, The End of Eternity The classic story about a culture meddling with the timestream, and political complications thereof.
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Stephen Baxter, The Timeships Brilliant sequel to H.G. Wells The Time Machine that deals with the effects of how time travel changes history and the cosmic consequences. Highly recommended.
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Greg Bear, Eternity Sequel to Eon. Major space-time engineering, advanced cultures mining other cultures for information and ultra-advanced civilizations with their own designs on the universe. Plenty of ideas for Ex cultures.
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Greg Egan, Diaspora A good description of posthuman societies and their exploration of the greater universe. Good mental training for dealing with time travel and the beings of Ex Tempore.
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Ken MacLeod, Cosmonaut Keep Humans dealing with far older non-human cultures and human cultures separated by centuries.
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Dennis Lindblom, Allt Har Sin Tid Story about some early time travelers and how they struggle to get home to their original timeline.
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Dennis Lindblom, Frostens Barn A good description of how an isolated community of humans develops faster and faster, essentially undergoing a singularity and becoming posthuman.
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Olaf Stapledon, Star Maker Grandiose novel about the evolution of life in the universe. Especially notable is the last part, where the Starmaker experiments with different universes this is the kind of things some of the mainliners like to do.
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Vernor Vinge, A Fire Upon the Deep Space opera in a world where both primitive, advanced and postintelligent civilizations coexist.
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