Xeelee Sequence

Science fiction series by Stephen Baxter

The Xeelee Sequence [a] is a series of hard science fiction novels, novellas, and short stories written by British science fiction author Stephen Baxter. The series spans billions of years of fictional history, centering on humanity's future expansion into the universe, its intergalactic war with an enigmatic and supremely powerful Kardashev Type V alien civilization called the Xeelee, and the Xeelee's own cosmos-spanning war with dark matter entities called Photino Birds. The series features many other species and civilizations that play a prominent role, including the Squeem, the Qax, and the Silver Ghosts. Several stories in the Sequence also deal with humans and posthumans living in extreme conditions, such as at the heart of a neutron star (Flux), in a separate universe with considerably stronger gravity (Raft), and within eusocial hive societies (Coalescent).

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