• The official report concludes that her parents committed suicide together when she and her brother were relatively young, leaving her and her brother feeling that they were abandoned.
• Her brother sustains life-threatening injuries after he is struck by her boyfriend's car, though it is not clear who is to blame for the accident.
• She lies to her boyfriend when they first meet at a math conference so that he will not know she is related to two famous mathematicians.

Mimi's brother, Art Brotherton, is the sort of stereotypical mathematician one often sees in works of fiction. He speaks in an old-fashioned and stilted manner. He is arrogant and obnoxious. He takes prescription medications to treat his paranoia. He is sufficiently anti-social that he remains a virgin into his thirties. And he thinks about numbers to calm himself down when he is worried. In fact, he thinks about numbers nearly all of the time. He is quite obsessed with his research into the famous open problem known as "P vs. NP". And, when his sister begins trying to find a boyfriend, he insists that she use the mathematically optimal technique of dating a pre-determined number of individuals first and then settling on the next one who passes a certain threshold. (Art also happens to be gay. I don't normally think of that as being an aspect of the "mathematician stereotype", but I have seen it in a lot of fiction lately and so I am beginning to wonder if it might now be part of it.)

Her boyfriend, Frank, though slovenly and happy to talk about math frequently, breaks these stereotypes by being spontaneous, fun, and romantic. We learn that Frank left academia and now works for a professional mathematical society in an administrative role. Whether the author intends this or not, I suspect that this will give many readers the impression that success as a research mathematician is necessarily tied to those anti-social traits while mathematicians who are more "normal" will migrate into non-research positions. In any case, Art is suspicious of Frank's true motivations (and not only because Mimi has settled on him before dating the pre-determined number of individuals).

Aside from discussions of P vs. NP there is also a bit about Chaos Theory, Game Theory, and the Halting Problem in this book. Contrary to what one might guess from the title, there is nothing about mathematical physics or a unified field theory.

The mathematical ideas are not explained particularly well in the book. For anyone who is consulting this page for some insight into the mathematics, let me briefly say: "P" and "NP" are two classes of mathematical problems that are defined by how quickly the number of steps an algorithm would need to answer them grows as a function of a parameter "n" on which they depend. A good example to keep in mind is finding the shortest path through n different locations on a map. When n is very large, this problem apparently becomes quite difficult to answer. In theory, the questions in the set NP which are not in P will take more steps to compute for large enough values of n than those in P but nobody has yet proved that this is true. It could be that the two sets actually contain exactly the same collections of problems. If P=NP is true, then that would basically mean that there is a way to solve the problems we think of as NP-hard much faster than any we currently know when n is large. (However, contrary to what nearly every source including this book implies, merely knowing that P=NP would not itself necessarily allow us to answer those questions quickly. It would tell us there is a quick way, but we still might not know what it is. Moreover, even if P and NP are equal the number of steps required to answer any given question for a given value of n could still be impractically large.) The Halting Problem is not in P or NP. It is famously a question which is known to not be solvable by any algorithm at all.

I am grateful to my student Terence Carey for bringing this book to my attention.