Frederik Pohl and Jack Williamson’s 1975 Farthest Star is the first novel in the Cuckoo duology, which was a fixup of the 1973 novella Doomship (1973) and the 1974 serial The Org’s Egg,
Farthest Star is an example of the Big Dumb Object school of science fiction. This makes it cousin to such classics as Ringworld, Rendezvous with Rama , and Orbitsville, as well as to books like The Wanderer .
By the late 21 st century, humans have made contact with a loose association of alien civilizations. These civilizations are linked, not by physical spacecraft, but by near-instantaneous tachyon communication. Tachyon beams carry information; they cannot transmit matter, but material objects can be scanned., That information can then be transmitted by the tachyon transporter, to be duplicated at a distant location 1. This tech has allowed humans to join the association and travel, as copies, to other worlds.
What if the traveller dies? Run off another copy. Or another dozen copies. Just ask the ill-fated Ben Pertin.