Summer 2003


A Matter of Degrees – Writing for the General Reader

Gino Segre

About five years ago I decided I wanted to write a book. My impending sixtieth birthday motivated part of the desire. It put me in a reflective mood, setting me thinking about what science means to me. I was trying to integrate my thoughts, my experiences and see if I could shape them, at least for myself, into a coherent narrative of sorts.

My career at the time had been a not untypical one for my generation- undergraduate at Harvard, graduate student at MIT, postdoctoral fellowships at CERN and Berkeley and then a long career on the faculty at the University of Pennsylvania. I was and still am a high-energy theoretical physicist, working on elementary particle physics problems often bordering on areas in cosmology and astrophysics. That, however, was not what I wanted to write about.

Most books written by scientists for a general public are attempts to describe the excitement and accomplishments of their own field, but there already were a number of excellent books about elementary particles and cosmology and I felt I had little or nothing to add to the existing literature. I also wanted to use writing as an excuse for learning more about aspects of science that were perhaps related, but went beyond my area of expertise. I always have had broad interests, subscribing to Nature, Science and the Scientific American. While I don’t read these cover-to-cover, I follow from afar the exciting developments in a number of fields.  My book, I postulated, should encourage me to follow up on some of these interests.

Like all scientists, I have specialized in order to succeed but, in writing, I wanted to be more of a generalist. The initial challenge I set myself was to see if the book, whatever its eventual subject matter turned out to be, could include the major scientific advances revolving around the beginnings of the Universe, of life and of the Earth.  Alternatively stated, I wanted to include the Big Bang, DNA and Plate Tectonics. How to do it was the question that drove me back to the drawing board.

I started by asking myself a very basic question, the first one usually posed in a physics course for non-scientists. What is science? We normally start, and I know many of you have had the experience of teaching such courses, by trying to explain the scientific method: measurements, incorporating results into a model, testing that model, drawing conclusions and then re-starting the cycle. Attempting to answer the question of what is science, I realized it all begins with measurements and that, at least in the physical sciences, there are only a few basic kinds of measurements.

These are length, time, temperature and perhaps mass. Of course our instruments are extraordinarily sophisticated, but the questions we asked are often quite simple. Focusing on the first three, length, time and temperature, I realized that a book about temperature would give me the opportunity to discuss the three big origins issues I wanted to include and hopefully tie them together in a way that would be accessible to the general public. Temperature would also allow me to give readers a window into problems of contemporary science. Perhaps I should let the book speak for itself. Its introduction concludes