Dark Matter, Neutrinos, and Our Solar System

Dark Matter, Neutrinos, and Our Solar System, Nirmala Prakash, World Scientific, 2013. $77.00 (676 pp.). ISBN 978-981-4304-53-5

I appreciate the book Dark Matter, Neutrinos, and Our Solar System, by Nirmala Prakash. This work is quite unconventional in many aspects; actually, its style resembles a large edited scrapbook in which an amazing bunch of subjects have been recorded for further thought. The author´s preface actually states something like this; the result is quite eclectic in breadth and in its attempt to intermingle the many subjects.

The first chapter, which discusses the advent of dark matter, is supposed to motivate the rest of the book. That approach sounds promising, but I found the presentation to be sketchy. The next two chapters, containing well-known information about stars and cosmology, seem unrelated to the book’s central topics. To be clear, the presentation in those chapters is accurate, but given the presumed background of the intended audience, it could just as easily have been omitted. Chapter 4, devoted to black holes, is potentially more interesting and more pertinent to dark matter, but its tune is off. It contains some obvious shortcomings; for example, primordial black holes are not discussed as candidates for baryonic dark matter and are mentioned only briefly later in the text.

The core of Dark Matter, Neutrinos, and Our Solar System starts with chapter 5, a historical overview of particle physics. The technical content is at an intermediate level, in contrast to some difficult and less pertinent subjects, like Penrose diagrams presented in the earlier chapters. Nonetheless, the introduction in chapter 5 is undoubtedly useful, though perhaps it could have been expanded to better prepare the reader for what is to come.

Chapters 6, 7, and 8 represent the book at its best. In 280 pages they discuss the main issues behind the question of what dark matter actually is and, in particular, the role of neutrinos. Those chapters could be used for a graduate-level introduction to the subject and for physicists wishing to start their own studies. Chapter 8 deals with the timely and important issue of the supersymmetric particles known as WIMPs (weakly interacting massive particles)—including some discussion of how they might be detected. That chapter concludes the book’s explorations of the main particle solutions to the dark matter puzzle.

To fully understand dark matter and neutrinos, the interested reader will need to seek additional material to supplement Prakash’s presentation. I cannot refrain from imagining an alternative plan for chapters 1 to 5 that would boost the material presented in chapters 6 to 8. But these observations do not diminish the merits of the book. The ninth and final chapter is a discussion that, although fascinating, again seems off-topic, at least on first reading. It is hard to imagine how Saturn´s rings or Mars rovers relate to dark matter. In my opinion, this solar system fraction of the book would be more appropriate as a separate text.

I also could not help but notice how the author transmitted her passion for the general enterprise of science; many of its historical and human aspects were scattered throughout the book. In particular, her mathematical background shows intermittently, in a sort of contrapunto to the physical and phenomenological subjects. Many readers will appreciate that passion, as I did, in this exuberant book.