A somber novel about an astronaut whose daughter dies tragically and wife leaves him while he is in space. Since he and his daughter were both mathematical prodigies, for whom math was not only a beloved subject but more importantly a common interest that bound them together, math is discussed frequently throughout the book. Many things are called "equations", whether or not they actually are, and as the title suggests, infinity appears as an underlying metaphor. In one remembered conversation, the father and daughter discuss "Hilbert's Hotel" and even introduce the notation א_{a}...but unfortunately the author does not really understand what he's talking about and gets the math wrong. (Indeed, as he says, there are different sizes of infinity, but the cardinality of the "hotel" after people have shifted rooms to make space for another guest is not an example of one.) [Followup: The author informs me that he is working to correct the mathematical errors in the paperback version and future editions. ak Oct 2012.] Still, the book is not actually about the math, it is about the emotions, and so it is more important that Kiefer succeeds in conveying the overwhelming grief of the protagonist.
