Soft Matter: The Stuff That Dreams Are Made Of,

New York
, 2011. $24.95 paper (293 pp.). ISBN 978-94-007-0584-5

A wise man once told me that before soft-matter physics was so named, the science of materials at the mesoscale was appropriately called De Gennes physics. How fitting, then, that Pierre-Gilles De Gennes was responsible for renaming “his” physics simply by titling his 1991 Nobel Prize lecture “Soft Matter.” The field has garnered as much attention for the quirkiness of its name as for the subtle complexities of the science it describes. On the 20th anniversary of the name change, we again find that this ever pliable subject is remodeling itself, in particular because of its many applications to biology. Could another name change be in order?

Regardless of what we call it, soft-matter science is familiar to the human experience. From the cream in our coffee to the cement in our buildings and sidewalks, we all experience the impact of soft matter firsthand (and foot). Such a seemingly familiar science may underlie the apparent disincentive for its experts to popularize it. The many mysteries contained in cosmology, particle physics, and relativity seem to justify their ever-increasing presence on bookstore shelves. However, it appears that the mysteries contained in commonplace materials have been underappreciated.

Satisfying the need of those who seek deep mysteries is Soft Matter: The Stuff That Dreams Are Made Of by Roberto Piazza. The book strikes the right balance between historical context and scientific content, and it should appeal to PHYSICS TODAY readers. As a soft-condensed-matter physicist, I find my own soft-matter dreams often turning into nightmares when I realize that I actually have to teach the subject to students. What keeps me up at night is the overwhelming breadth of knowledge needed; to convey the material requires a comprehension of fundamental applications of electrodynamics in continuous media, statistical thermodynamics, and the physical chemistry of everything from colloids to peptides, among other things. Piazza adroitly tackles the hardest parts of soft matter, providing sufficient breadth to explain its ever-increasing canon in a way that will make sense to the undergraduate student.

One of Soft Matter’s dreamy aspects is the way in which some topics are contextualized. For example, though somewhat curious in its delivery, the prelude, which Piazza calls “Overture: a special day,” takes the reader through a day in the life of a working mother by highlighting the indispensable role played by soft materials. The book is full of that type of unconventional storytelling, which perfectly suits the subject.

Early on, Piazza introduces the quintessential soft material—colloidal dispersions, such as coffee, milk, and toothpaste, to name just a few—thus setting the stage for a discussion of the fundamental forces that determine mesoscale interactions. As the book proceeds, colloids give way to polymers with classic treatments of random-walk models and the origins of elasticity. Near the middle, the focus shifts to macromolecular self-assembly and amphiphilic molecules and to a description of packing, structure, and geometry that leads naturally into a discussion of glassy materials and jamming in granular materials. In the latter section, Piazza takes the reader into what he seems to anticipate will be a direction for soft-matter science—biology. As a community, soft-matter scientists appear to be moving toward applying soft-matter tools and techniques to biological materials.

I wish that books like Soft Matter existed when I was a student struggling to understand exactly what the term meant. The book’s glossary alone is a valuable resource that many students entering the field will likely turn to while taking courses and after incomprehensible seminars. I am certainly going to make this excellent book part of the required reading for all students taking my introductory class on the subject.