THE ELEGANT UNIVERSE, Brian Greene, 1999, 2003
```(annotated and with added bold highlights by Epsilon=One)
While writing The Elegant Universe, I was aware that its readership might be meager. After all, a book about the challenges and triumphs of the modern quest for the deepest laws of nature is not something you imagine breezing through at the beach, or curling up with just before going to sleep. And a book that takes on such an abstract subject with the intention of emphasizing the science, not the scientific personalities or historical anecdotes, might seem to cater to an even smaller audience. But this didn't particularly trouble me, as I told myself frequently (and, no doubt, with a tinge of melodrama) that if I reached one person, introducing them to a new spectrum of ideas, a new way of thinking about themselves and their place in the cosmos, that would be enough. Be it a young student trying to decide on a direction of study, a working professional seeking something beyond the daily grind, or a retiree who'd finally found the time to read .up on developments in science, if I could help guide them toward the new view of the universe emerging from modern physics, the task of writing The Elegant Universe would have been worth the effort. That thought, at the very least, helped me through the demanding times that many an author encounters in the midst of a substantial writing project.
I was also encouraged repeatedly by audiences attending various general-level lectures I'd been giving on relativity, quantum mechanics, and my own specialty—superstring theory—who seemed enthralled by the strange and startling ideas emerging from cutting-edge research. A universe in which space and time are malleable, a universe with more dimensions than we see, a universe in which the fabric of space can rip, a universe in which everything might be composed of the vibrations of ultramicroscopic loops of energy called strings, was a universe that got people excited and one that many wanted to understand better. The Elegant Universe grew out of those lectures, as my intention was to write a book for those without formal knowledge of mathematics or physics to gain such familiarity. Although the book agent to whom I first showed my proposal rejected it outright—understandably predicting that the subject was too specialized to attract a mainstream publisher—I could feel the enthusiasm for the science when I was out lecturing in the field. It was palpable.
The Elegant Universe tapped into this enthusiasm, and the gratifying response it has received is testament to the innate drive so many of us have to explore thoroughly and courageously this place we call home. It also affirmed my belief that physics provides an author with some of the most wonderful material imaginable. We all love a good story. We all love a tantalizing mystery. We all love the underdog pressing onward against seemingly insurmountable odds. We all, in one form or another, are trying to make sense of the world around us. And all of these elements lie at the core of modern physics. The story is among the grandest—the unfolding of the entire universe; the mystery is among the toughest—figuring out how the cosmos came to be; the odds are among the most daunting—bipeds, newly arrived by cosmic time scales trying to reveal the secrets of the ages; and the quest is among the deepest—the search for the fundamental laws to explain all we see and beyond, from the tiniest particles to the most distant galaxies. It's hard to imagine a richer point of departure.
Nonscientists sometimes blur the distinction between the intimidating language—mathematics—in which physics is developed and the engrossing ideas with which it tussles. But that would be like my trying to assess Huckleberry Finn by reading it in Greek. While I use the Greek alphabet all the time, I don't speak a word of the language and so my impression of the novel would be, to say the least, compromised. Similarly, when the mathematical barriers are cleared, and the concepts of modern physics are expressed in familiar language for all to see and ponder, many who thought they had no interest in science find themselves captivated. When extracted from their technical incarnation, the themes of modern physics are, quite literally, universal.
Of late, this has become increasingly clear with physics' ever more visible cultural presence—there is a growing body of theatrical, musical, and artistic works that have drawn their inspiration from modern science. I'm aware of nearly a dozen recent plays, a full-length string quartet, a variety of films and numerous screenplays, an opera, a series of paintings and sculptures, that to varying degrees express, interpret, and extend the human drama of the scientific journey. Although wonderful, I don't find this particularly surprising. I've always been most taken with art and literature that gives a vigorous shake to my sense of what's real and important, an outlook that many people I've encountered also share. And this is just what the most far-reaching discoveries in physics during the last hundred years have done. It's no exaggeration to say that relativity and quantum mechanics rewrote the previously conceived rules of reality, and that, while more speculative, superstring theory is now generating major revisions once again. It is little wonder that artists, writers, composers, and filmmakers are finding resonance between their work and these scientific challenges to the status quo.
And it's not a one-way street. Integrating the discoveries of physics into our collective worldview is a slow process. Even today, nearly a century later, most people have yet to appreciate fully the experimentally confirmed lessons coming from Einstein or those of the quantum. By fearlessly taking on the science, and leveraging its intrinsic fascination to produce entertaining works of substance and drama, the arts may well be the perfect medium to fully integrate science into the world's conversation. We may even find that the art world's scientifically inspired works will provide new stimulus to the scientific imagination and, in some possibly intangible way, prepare us for the next step in understanding the universe. Certainly, shifting the sharp spotlight illuminating science from the purely rigorous, numerical, and cognitive, to one with the softer, more ambiguous glow of human sensibilities, is enormously potent. When science is widely seen as an integral part of what makes us human, our own connection to the cosmos will be significantly strengthened; truly, science is the thread that weaves us all into the fabric of reality.
As far as developments in superstring theory go, the years since the initial publication of The Elegant Universe have been extremely productive, but there's yet to be the revolution in thinking that many suspect is still lurking just around the corner. This has ramifications that are both good and bad. On the positive side, nothing in the text has become outdated or irrelevant. Were I writing a book on string theory today, I'd cover everything I do, perhaps with a change in emphasis here or there, but the result would be for the most part largely indistinguishable from The Elegant Universe. The two most significant changes would be to add a chapter on interesting new ideas suggesting that strings and the extra spatial dimensions they require are somewhat larger than conventionally thought (a possibility that was just being developed during the writing of The Elegant Universe; you will find it briefly discussed in various endnotes) and a discussion of ingenious new work seeking a more exact (a so-called nonperturbative) formulation of string theory. So, as you read Chapters 6, 8, and 12, keep in mind that strings and extra dimensions might not be quite as small as I describe, and that significant progress has been made in finding string theory's exact equations (although, as yet, physicists have not succeeded in applying these equations to resolve key questions raised in those chapters).
The negative side of the text not requiring a major update is that many of the obstacles described have yet to be surmounted. Frankly, while we all want progress to be fast and furious, this is par for the course. Superstring theory is tackling the most fundamental problems in theoretical physics, many of which are well beyond the reach of experimental guidance. The payoff of success would be huge, as some of the deepest questions about the cosmos could well be answered. But progress requires hard work, patience, luck, and a significant amount of inspiration—just the ingredients whose time scales for success are beyond our control or prediction.
Maybe we will reach the sought-after level of insight during our generation, and maybe we won't. Maybe it will be many generations down the road. The only thing we can say for sure is that we won't know if we don't try. Judging by the ever more talented graduate students entering the field, we will have many enthusiastic researchers ready to grab the torch and head further down the path. We will be trying, zealously trying, to unravel the mysteries of the cosmos for years to come.