About the Book

This low-cost reissue of Biological Physics is intended to be plug-compatible with the 2014 edition; even the numbering of problems has been left unchanged. However, I have taken the opportunity to add many clarifications, update figures and references, and so on.

The only prerequisite for the main text is first-year undergraduate physics and corresponding math. Supplementary sections make the book also suitable as the basis of a graduate-level course.

Dozens of exercises are included at all levels of complexity, many involving computer work. Full solutions are available to adopters.

The e-book is available for $9.99 from Amazon. Its ISBN number is 978-0-578-69547-1. Note that this fixed-format book works best on a big screen, e.g. Kindle app for a laptop or desktop computer.

The paperback book is available for suggested retail $29.99. This site conveniently looks up who is offering it and compares prices. For individuals, may I suggest ordering through a local bookshop in your community using its ISBN number: 978-0-578-68702-5. University bookstores can get it from Ingram. Bookstores outside the US can open a free ipage account and then order through that ipage account.

The Contents, "To the Student," and "To the Instructor" are freely available here, as well as Chapter 1.

Errata are here.


With its integrated approach, Biological Physics can be used as the basis for interdisciplinary courses in biophysics, bioengineering, or nanotechnology. Throughout, the goal is for students to gain the fluency they need to derive every result for themselves. To that end, the text includes exercises at all levels of complexity, including many that guide students through computer-based solutions.

Readers will acquire several research skills that are often not addressed in traditional courses:

These basic skills, which are relevant to nearly any field of science or engineering, are presented in the context of case studies from living systems, including:

Intended Audience

Who takes this class?

At my institution, the students are undergraduates who have taken one year of university physics. No background in computer programming, and no Biology or Chemistry prerequisite courses are assumed. However, each chapter has a ”Track 2” appendix with more advanced material; with these sections and some assigned primary research articles, the book can also serve a graduate–level course.

Although the book is not about medicine per se, many students who take the course at Penn are premedical, in part because the course addresses many of the competencies that form the basis of the MCAT (see the MCAT guide).

The book has almost no overlap with my other books From Photon to Neuron and Physical Models of Living Systems. Photon to Neuron focused on light in biology, including optical instruments as well as animal vision. Physical Models of Living Systems focused on intracellular control systems, and on general background skills.

Instructor Resources

The graphics will be freely available in a form suitable for classroom use. Additional Instructor Resources, including solutions to the problems and ideas for classroom demonstrations, will be available from the author.

Responses to the Student Edition:

“This clear and well-structured text emphasizes the connections between statistical mechanics and biophysical phenomena.”

R. Parthasarathy, in Am. J. Physics 2021

Responses to the first edition:

“This book inspired me to write [my] book in the first place. Biological Physics is the most interesting and well-written textbook I have ever read.”

Peter M. Hoffman, in "Life's Ratchet"

“Philip Nelson's excellent text provides material for the types of course we should now be offering to all our students.... There are frequent comments about the way that modern ideas and techniques have emerged. As Nelson cleverly shows, many of the most important scientific breakthroughs have come about unexpectedly through just the type of interdisciplinary studies that this book promotes.”

Christopher Dobson, in Nature

“This creative and insightful textbook brings definition to the field and establishes a set of central themes, based on principles of statistical physics.... Always maintaining a solid physics perspective, [the book] explores biological macromolecules, their structures and self-assembly, biomotors and locomotion, neurons, and more. The book is... a fascinating tour that will bring the reader within reach of many current research topics... It will intrigue both the student and the professor.”

Stephen Hagen, in American Journal of Physics