The space ship Leonora Christine gets irreparably damaged and now can’t stop accelerating. As the ship approaches light speed, time slows down on board and the crew witness eons and galaxies go by, all the way up to the dissolution of the universe.
Poul Anderson was a prolific SF and fantasy author, producing about a 100 books in 50 years’ time. This was at a time when science fiction books were still around 200 pages, but a staggering bibliography nonetheless. A handful of his best have always remained in print, and Tau Zero is one of them. By some seen as the quintessential hard-SF book, the science drives the plot while the characters merely try to cope with what’s happening.
At the start of the novel, a Star Trek like surrounding is sketched. We meet the ship and its crew and the facilities on board. 25 men and 25 women, a colonization mission to a planet 30 lightyears away. Except, this Star Trek show goes the furthest away in time and space as is possible. There’s lots of science talk at the start to underscore the tone of the book. The characters are all struggling with saying goodbye to Earth.
Poul Anderson decided to kick against a couple of shins. A book published in the 70s in the US, and the only American in the book on board of the Leonora Christine is loud and violent, and can’t handle that the US is no longer the powerful hegemon among humanity. Also, everyone in the book is having sex with each other under the name of open-minded feminism and romanticism, and it is causing all sorts of relationships problems and drama on board. The female characters are sleeping around and the male characters have more traditional values and get upset. In the end, Poul lets it evolve into stable relationships.
The storyline has a very interesting parallel development: as the eternal acceleration problem gets more extreme, the tensions on board the ship start to grow too. You start to wonder how worse things can get and what the end will be like.
The book isn’t perfect. It’s short and the characters are not very involving, although Anderson has a deft hand at description and has no problems fleshing the characters out in an adequate way. What could have been done better was a sense of how much time has passed inside the space ship. The tension keeps on rising inside, but you get the impression that it is a matter of weeks or months, while Anderson is actually talking about years.
In the end, the physics are the star of the book. The endless acceleration and what happens when you extrapolate that to the extreme, to the end of time and space, and how a small space crew tries to deal with that. That is what drives the story and the reader’s interest. At least, it should. If that doesn’t interest you, I would not recommend the book, but at the same time it is a very nice and classic science fiction story about the immensities of space and time.