Dan Falk - In search of time: journeys along a curious dimension

Youre writing a book about what?

Tell people youre working on a book about time, and you get some interesting reactions. Some look confused, or give a dismissive shrug What about time, they ask, as though there could hardly be enough interesting things to say about it to fill an entire book. (Doesnt it just sort of tick by?) Others seem to understand the appeal right away, and wonder about particular topics. Will you talk about time travel? Yes, I affirm it gets a whole chapter to itself. (Even if time travel is impossible, I tell them, it raises fascinating questions about the nature of time, space, and the laws of nature.) Some people guess that I must be writing a physics book highly technical, with much talk of entropy and world lines and such. Not so, I assure them. Or at least not just a physics book. My goal is to take a broader approach, tackling the enigma of time from several different directions, each with its own perspective and insights and its own track record of successes and frustrations.

In fact, one has to approach time from many such angles, because no one discipline has the answer. That fact was apparent whenever I glanced at the books that line the shelves in my apartment. (There would, of course, be many trips to many libraries, but one of the joys of building up a decent home collection is that quite a good chunk of research can be done before one even braves the elements.) My first couple of shelves cover the history and philosophy of science: this is where I reach for classics like Bronowski and Boorstin and Gamow, a cluster of Carl Sagan titles, and more recent works by Timothy Ferris and Dennis Danielson, to name a few. Beneath that, the scientific biographies: Drake and Sobel on Galileo; Westfall and Gleick on Newton; Pais, Flsing, and Isaacson on Einstein; and other more narrowly focused titles on the theories crafted by those great minds. Under that, a shelf of modern physics and cosmology titles: Hawking, Weinberg, Greene, Davies, Rees, Krauss, and others. On the next shelf, books on evolution and the nature of the human animal: Diamond, Tattersall, Dawkins, Hauser. Below that, books on consciousness and the mind: Pinker, Penrose, Dennett, Crick, Damasio, Edelman. Not to mention some very thorough books on clocks, calendars, and timekeeping: Whitrow, Aveni, Landes, Duncan, Steel.

And time well, time reaches across all of those fields. In fact, one of the challenges is that each of these disciplines is to some degree intertwined with each of the others. Interconnectedness is fine if youre building a spider web, but it can actually hamper the writing of a book, which demands a single flowing narrative a story. To tell that story, Ive had to be selective. Where there was a choice between more science and more philosophy, the science usually won out not because the philosophy is uninteresting, but merely because I found it to have less power to advance the story. (What, no Heidegger? No Bergson? Sadly, no; we will have to make do with Plato, Aristotle, Leibniz, McTaggart, and a handful of other key players.) Even within the sciences, there is far too much current research to assess in a single volume; indeed, each of my twelve chapters could easily have been a book in its own right, for an author so inclined. For those who do wish to probe deeper, I hope that detailed notes and a full bibliography of sources will aid in further reading. In the text itself, I have tried to make my selections as carefully as possible, giving the most attention to those areas where science has made the most tangible advances in recent years.

Research begins with books and journals and libraries, but it does not end there: over the last few years, it has been my great privilege to meet with some of the deepest thinkers of our time, in some cases for multiple interviews. It will only take an hour, I would tell them, knowing full well that it would run much longer and most of them generously allowed me to keep asking away, microphone in hand. I am especially grateful to Roger Penrose, Julian Barbour, David Deutsch, Lee Smolin, and Paul Davies; their grasp of some of the most difficult problems in all of science is truly inspiring. Many more scholars sat down with me and patiently described their research; others guided me through laboratories, museum exhibits, and archeological sites. They are named in the chapters ahead, and I am indebted to them all. (Most of these interviews were conducted specifically for the present book, but I have also occasionally drawn on research for various earlier projects, including several documentaries that I made for the CBC Radio program Ideas.)

A number of people generously looked over portions of the manuscript at various stages; Ivan Semeniuk, George Musser, and Natalie Munro made especially valuable comments, while Elizabeth Howell was kind enough to read the entire text. (Of course, any errors that remain are my responsibility alone.) I also benefited greatly from discussions with James Robert Brown, Glenn Starkman, and Eugenie Scott.

The idea of writing a book about time had been in the back of my mind since the completion of my first book, Universe on a T-Shirt: The Quest for the Theory of Everything (2002). This book is by no means a sequel; the subject matter is, in general, quite different. But certain key topics special relativity, for example do come up again; on occasion, I refer the reader to more detailed explanations in the earlier book.

This project would not have come to fruition without the help of my agents, Don Sedgwick and Shaun Bradley of the Transatlantic Literary Agency, and especially the tireless work of my editor, Jenny Bradshaw at McClelland & Stewart, who helped hone the manuscript into its finished form. I am also grateful to Stephanie Fysh for her copy editing skills.

Where measurements crop up, I have once again primarily used metric units; I trust that my U.S. readers will not have too much trouble with meters, kilometers, and the like. On the other hand, I have used American spellings, which I hope will not alienate my Canadian audience.

Readers comments are welcome; I can be reached through my website at www.danfalk.ca.