Raft (novel)
A hard SF novel set in a high-gravity alternate universe.
Raft is a 1991 hard science fiction novel by British author Stephen Baxter. It marks both Baxter's debut novel and the first installment of the Xeelee Sequence, although the Xeelee themselves are absent from the story. The book received a nomination for the Arthur C. Clarke Award in 1992.
The novel expands upon Baxter's 1989 short story of the same name. Its plot follows a group of humans who inadvertently enter an alternate universe where gravity is roughly a billion times stronger than in our own. In this reality, planets cannot form because they would instantly collapse under their own gravity; stars measure only about a mile across and burn out quickly, leaving behind cooled cores a hundred yards wide with a surface gravity of five g. Human bodies themselves generate a "respectable" gravitational field. The setting also features "gravitic chemistry," in which gravity dominates atomic-scale interactions.
The human population, numbering a few thousand, survives within a nebula of breathable air, but their society is sharply divided. The elite live on the "Raft," the remnants of the starship that holds most advanced technology. Workers and miners inhabit "Belt" worlds, where they extract material from burned-out star kernels. A nomadic group called the "Boneys" lives on worlds constructed from corpses and is considered unmentionable.
The story does not directly explain how humans arrived in this universe, though hints suggest the Raft ship entered through a rift from our own reality. The original short story offers more detail, stating that "five hundred years ago a great warship – chasing some forgotten opponent – blundered through a portal. A gateway. It left its own universe and arrived here." A later book in the sequence, *Ring*, suggests the humans originated from the main Xeelee Sequence universe, though the exact time period of their escape remains unclear.
The alternate universe follows the same physical laws as ours, except for its vastly larger gravitational constant. Over time, this altered physics has made the nebula increasingly hostile, and both the human inhabitants and the strange native species suffer from an ongoing environmental collapse.
- Author
- Stephen Baxter
- Published
- 1991
- Genre
- Hard science fiction
- Nationality
- British
- Series
- Xeelee Sequence
- Award nomination
- Arthur C. Clarke Award (1992)
Lore & Background
Raft is an elaborated version of Baxter's 1989 short story of the same title. The story follows a group of humans who have accidentally entered an alternate universe where the gravitational force is far stronger than our own, a 'billion' times as strong. In this universe, planets do not exist, stars are only a mile across with extremely brief life-spans, and human bodies possess a 'respectable' gravity field. 'Gravitic chemistry' exists, where gravity is the dominant force on an atomic scale.
The few thousand humans survive in a nebula of relatively breathable air, living in divided communities. Society is highly stratified: the elite live on the 'Raft' (the remains of the starship containing almost all high technology), workers/miners live on 'Belt' worlds mining burned-out star kernels, and the 'Boneys' are a nomadic band of 'unmentionables' living on worlds created out of corpses. It is not directly detailed how humans came to the universe, but hints indicate the Raft ship came through a rift from our universe. The original short story provides more insight: 'five hundred years ago a great warship – chasing some forgotten opponent – blundered through a portal.'
Reader's Guide
Raft is significant as Stephen Baxter's debut novel and the first entry in the Xeelee Sequence, a major series in hard science fiction. The novel explores extreme gravitational physics, presenting a universe where gravity is a billion times stronger than in our own, leading to unique phenomena such as mile-wide stars and gravitic chemistry. The book's nomination for the Arthur C. Clarke Award in 1992 highlights its impact within the genre. The novel's setting—a nebula undergoing environmental collapse—and its stratified society reflect themes of survival and resource scarcity. Though the Xeelee are not present, the novel establishes the broader universe of the sequence, with a later book, Ring, implying that the humans in Raft came from the main Xeelee Sequence universe, though the time period of their escape is unclear. The work remains a key example of Baxter's rigorous scientific extrapolation and world-building.
Did You Know?
- Raft is both Stephen Baxter's debut novel and the first book in the Xeelee Sequence.
- The novel was nominated for the Arthur C. Clarke Award in 1992.
- The story is an elaborated version of Baxter's 1989 short story of the same title.
- In the alternate universe, gravity is a 'billion' times stronger than in our own universe.
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