In the hard-science Tomorrow & Tomorrow, Sheffield explores changes in the solar system and the theory of a closed vs. open system wrapped around a tale of a musician’s fanatical love for his wife. Drake Merlin has his dying wife Ana and himself cryonically frozen so they can be together once a cure for her disease is found. Several times over 15 billion years he is awakened only to find no cure and, one time, he accidentally causes Ana’s death. But if the theory of a closed system is true and the universe shrinks, he and Ana can return to a point when she is alive.