Although there are plenty of clues to the knowledgeable reader that Schwartz is not an expert on mathematics, she does quite a good job of writing about a math professor. Caroline is a knot theorist, and a few terms of knot theory are tossed around casually and correctly (e.g. she searches for "knot ivariants" and studies "knotted spheres in four-space"). We hear a bit about teaching introductory calculus, meeting with graduate students, collaborations (he is described as having "flights of algebraic genius" while hers are "geometric") and conferences. For the most part, the mathematics does not add much to it, but unlike many works of mathematical fiction written by authors who do not know the mathematical community, it is done well enough that it did not detract from my enjoyment of the book either.

Perhaps my favorite mathematical moment is when a topological metaphor is used to justify (in Caroline's mind) her extra-marital affairs:

This is the one case in which I found a true synergy between the literature and the math. Otherwise, the math just sits there nicely as the story progresses.

Much is made of the fact that Caroline was "one of the few women in a man's field". For instance, that she is able to get a job at a small, unnamed college in the middle of nowhere is ascribed to "her notoriety as a female researcher". Today, these descriptions of a sexist mathematical community seem harsh. But, it may well be that in 1980 when the book was written this was an accurate description of the environment.

Of course, I have spent all of this time discussing the mathematical aspects of the book when it is really about human relationships: how husbands and wives get along and how they don't, how children affect their relationship, what keeps them together and what drives them apart. This is, of course, the main focus of most of the reviews of this book, so I will only refer you to those and add that this book deserves the critical success that it enjoyed.