Time travel is a well-explored concept to say the least in Science Fiction. From "The Time Machine" to "The Terminator" to "Futurama", SF fans have read and watched as wave after wave of time travelers travel through time, creating ripples of paradox in their wake. In most works, the time traveler is exempted from paradoxes, and can witness the effects of the changes they make in the full knowledge of how the new world compares to the world they left behind. To name just a few examples:
- In Ray Bradbury's "Sound of Thunder", a time traveler steps on a butterfly in prehistory and returns to an altered (and diminished) present.
- In the "Back to the Future" series, numerous characters change the present by altering the past. The main character fades into a ghostly half-existence when he threatens to undo his parents' marriage.
- In the "Yesterday's Enterprise" episode of "Star Trek: The Next Generation", a ship is sent forward in time and (as a result of its absence at a key point in history) encounters an altered future.
- In Orson Scott Card's "Pastwatch", travelers from the future make changes in the time of Columbus to ensure that European and American cultures meet as equals.
Another good example is the relativistic time traveler, a person from our time who travels close to the speed of light and reaches their destination hundreds or thousands of years in the future. In works like "Planet of the Apes", these characters help bring drama to the story. "Planet of the Apes" would have been a very different work if there were no astronauts from our time involved in the story. We might simply see a cross-section of ape society from the point of view of a chimpanzee archeologist who discovered the ruins of the Statue of Liberty. In the right hands, it could still be dramatic, but it would be a slower-paced and more challenging kind of drama than following Charlton Heston as he bellows, outraged, through the world of the apes.
These two pillars of time travel works are incredibly common and (on the whole) enjoyable, but after so many variations on a similar theme, it's refreshing to encounter a book like "Timescape" that has something new to offer. The first key difference in "Timescape" is that no one ever actually travels in time. Only information (in the form of tachyon beams) is sent into the past. The right information can change the future, and that's all that's needed to explore the idea of paradox in more detail.
This brings us to the second key difference in "Timescape", which is the way in which paradoxes are handled. Benford's treatment is elegant and surprising, and evolves naturally as the characters involved (many of whom are research scientists) become aware of the possibilities. I'll avoid going into further detail to avoid spoiling anything for anyone who hasn't read the book.
Beyond those two variations, "Timescape" is a solid novel with good characters and story. We follow two sets of main characters, one in a near future in which environmental ruin looms, one in a near past in which a young junior professor struggles to avoid becoming marginalized as he discovers a message from the future hidden in the background noise in one of his experiments. Both time periods are well-rendered and the characters are memorable, even if in some cases they aren't particularly likeable.
This is a great novel with solid ideas and strong characters, and well worth a read.