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Authors: Freeman Dyson

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To achieve a stable equilibrium between the park and the settlers for centuries to come, it would be desirable to get rid of boundaries
dividing individual islands. Boundaries could be redrawn so that each island is wholly in the park or wholly outside. For example, the two heavily populated islands Santa Cruz and San Cristóbal might be opened and the two lightly populated islands Isabela and Floreana might be closed to settlers. If this land swap were done now, it would require moving about 4,000 settlers out of a total of about 40,000.

The advantage of the deal for the park would be to gain complete control of the biggest island, Isabela, which is also the most diverse ecologically and geologically. The advantage for the settlers would be to possess two complete islands with a large net increase of territory. The division of land area between park and settlers would become about 85 to 15 instead of the present 97 to 3. Whether such a resettlement can be negotiated, either now or in the future, remains to be seen. The disadvantages are as obvious as the advantages: for the settlers, uprooted lives, and for the park, diminished territory. Most likely, the present division of the islands will last a long time, until some quarrel between park and settlers causes an acute crisis and compels the national government to impose a more stable arrangement.

Since I grew up in England, I tend to think of all environmental problems in terms of English analogies. England emerged out of the last ice age only 15,000 years ago, even more recently than the Galápagos emerged from the ocean, and was colonized by species migrating from the European mainland. After the newly arrived species, human settlers came to England. When they arrived, England was a pristine wilderness, and we may imagine an international park administration set up then to preserve the ecology. What should the park administration have done? What fraction of the land should have been set aside as a permanent wilderness, and what fraction should have been open to settlers? We may imagine the park administration and the settlers quarreling about these questions in England, just as they do in the Galápagos today.

In the real world, when the settlers arrived in England ten thousand years ago, there were no park administrators and no barriers to settlement. England was overrun with settlers who did what they pleased with the wilderness, first building forts on hilltops, then chopping down trees and converting forest into farmland, then building villages in valleys and cities beside rivers, then covering the country with furnaces and factories and railways and roads, polluting the air with soot and the rivers with sewage. While they were destroying the wilderness and transforming the ecology, the settlers incidentally built cathedrals and gardens, wrote plays and poems, invented machines and discovered laws of nature. Finally, in the last century, the settlers, now fifty million strong, began to clean up the environment and take care of the wildlife. Today the English countryside is entirely man-made, quite different from the original wilderness of uninterrupted forest, but it is still beautiful, rich in its variety of habitats and species. This English history raises another question. If England had been governed for the last ten thousand years by a park administration, would the final result have been better?

After examining the example of England, I do not know whether, in the long run, any international park regime dedicated to preserving the wilderness could have achieved a better result than the settlers who took possession of the land free of all restraint. Taking a long view, I am equally uncertain about the future of the Galápagos. It may well be that in the long run the settlers will do better than the park. Human settlement and wilderness are equally a part of nature, and our task as custodians of the planet is to help them to coexist peacefully. To take care of the islands in the long run, we need both the park administration and the settlers. We cannot know what problems they will face. A human presence in the islands is important not only for the future of the Galápagos but for the future of Ecuador as a whole.

After our week in the islands, we spent a second week in Ecuador, in the Amazon jungle east of the Andes. We stayed at Sacha Lodge, a tourist hotel deep in the jungle. The long trip down the river to the lodge reminded us of Conrad’s
Heart of Darkness.
Our professional guides in the jungle were Amazonian natives who had grown up in that part of Ecuador. One of them had been raised by a grandfather who was a shaman, using the medicinal plants of the jungle to heal wounds and cure diseases. The grandson speaks five languages fluently: Spanish, English, and German as well as two native languages. Just as in the Galápagos, the guides are passionate environmentalists, expert in the ecology of the jungle, and also well informed about the human problems of the Amazon region. They intend to retire, as soon as they have saved enough money, to jobs in the private sector. They see the Amazon region, like the Galápagos, as a land of opportunity. For them too, ecological preservation and human presence go hand in hand.

Note added in 2014: I was disappointed to receive few responses to this review. Those that I received were mostly from people who intended to travel to the Galápagos and asked for practical advice. Nobody responded to the question that I asked about the ecological future of the islands. I still believe that I learned an important lesson from my visit, and that the lesson has important implications for people living in other parts of the planet where natural beauty is endangered by human settlement.

*
Paul Stewart et al. (Yale University Press, 2007).


See also Peter Grant and Rosemary Grant,
How and Why Species Multiply: The Radiation of Darwin’s Finches
(Princeton University Press, 2007).

8
LEAPING INTO THE GRAND UNKNOWN

FRANK WILCZEK IS
one of the most brilliant practitioners of particle physics. Particle physics is the science that tries to understand the smallest building blocks of earth and sky, just as biology tries to understand living creatures. Particle physics is running about two hundred years behind biology. In the eighteenth century, Carl Linnaeus started systematic biology by giving Latin names to species of plants and animals,
Homo sapiens
for humans and
Pan troglodytes
for chimpanzees. In the nineteenth century, Darwin created a unified theory for biology by explaining the origin of species. In the twentieth century, Ernest Rutherford laid the ground for particle physics by discovering that every atom has a nucleus that is vastly smaller than the atom itself, and that the nucleus is made of particles that are smaller still. In the twenty-first century, particle physicists are hoping for a new Darwin who will explain the origin of particles.

It is too soon to tell whether Wilczek will be the new Darwin. His book
The Lightness of Being
*
is not the new
Origin of Species.
It is more like Darwin’s
Voyage of the Beagle
, a popular account of a voyage of exploration, describing the landscape and the newly discovered
creatures that still have to be explained. Wilczek is a theoretician and not an experimenter. His strength lies in leaps of the imagination rather than in heavy hardware or heavy calculations. He shared the 2004 Nobel Prize in Physics for inventing the concept that he called “asymptotic freedom.”

He writes as he thinks, with a lightness of touch that can come only to one who is absolute master of his subject. He borrowed his title from Milan Kundera, the Czech writer whose novel
The Unbearable Lightness of Being
takes a gloomier view of lightness. For Wilczek, the lightness of being is not only bearable but exhilarating. He says:

There’s also a joke involved. A central theme of this book is that the ancient contrast between celestial light and earthy matter has been transcended. In modern physics, there’s only one thing, and it’s more like the traditional idea of light than the traditional idea of matter. Hence,
The Lightness of Being.

Wilczek has undertaken a difficult task: to describe the central problems of particle physics to an audience ignorant of mathematics, using few equations and mostly colloquial language. His idiosyncratic jargon words, such as Core, Grid, and Jesuit Credo, are explained in an extensive glossary at the end of the book. The glossary is fun to read, full of jokes and surprises. The words Core, Grid, and Jesuit Credo are not to be found in other books about physics. They are jargon invented by Wilczek to express his personal view of the way nature works. Core is like the core curriculum that undergraduates majoring in physics are supposed to learn. It is a solidly established theory, confirmed by experiments but still obviously incomplete. It is incomplete because it describes what nature does but does not
explain why. The glossary says, “The Core theory contains esthetic flaws, so we hope it is not Nature’s last word.”

Grid is Wilczek’s word for the stuff that exists in apparently empty space. According to his view of the universe, empty space is not a featureless void. It is a highly structured, powerful medium whose activity molds the world. He says, “Where our eyes see nothing, our brains, pondering the revelations of sharply tuned experiments, discover the Grid that powers physical reality.”

The Jesuit Credo refers not to a theory of the universe but to a way of approaching research: “It is more blessed to ask forgiveness than permission.” This is a rule propounded by the Jesuits for saints and sinners trying to find the right way to live. If you ask for permission, the authorities will probably say no. If you ask for forgiveness, they are more likely to say yes. Wilczek was brought up in a Catholic family with a proper respect for Jesuits. The Jesuit Credo is particularly helpful for a scientist trying to find the right way to think. It is more blessed for a scientist to make a leap in the dark, and afterward be proved wrong, than to stay timidly within the limits of the known.

The main part of Wilczek’s book, with the title “The Origin of Mass,” describes the Core theory, the part of particle physics that is firmly based on the weak and strong forces that we observe in nature. Atoms and nuclei are held together by forces acting between all the pairs of particles that they contain. Each force acts between two particles and its strength depends on the distance between the two particles. Weak forces hold atoms together and grow weaker at large distances. Strong forces hold nuclei together and grow stronger at large distances. Large distances mean distances larger than the nucleus of an atom, and small distances mean distances smaller than a nucleus. The doctrine of asymptotic freedom, which Wilczek discovered, says that the behavior of these forces at short distances is the
opposite of their behavior at large distances. At large distances, the strong force is strong and the weak force is weak, but at short distances the opposite occurs: the weak force grows stronger and the strong force grows weaker.

He called this doctrine asymptotic freedom because it implies that at high energies the strongly interacting particles become almost free. Strongly interacting particles are called hadrons, from the Greek word
hadros
, meaning fat. The higher the energy of a collision, the shorter the distance between the colliding particles. In collisions between hadrons with very high energy, the strong forces paradoxically become weak and the probabilities of collisions become small.

Another consequence of asymptotic freedom is that we can calculate the masses of hadrons, starting from a knowledge of the strength of the strong force. Masses calculated in this way agree with the observed masses of known particles. This is what Wilczek means by “The Origin of Mass.” The masses of familiar objects like atoms arise from the peculiar symmetry of the strong forces. Modern theories of particle physics have the marvelous property, first pointed out by the Chinese-American physicist Frank Yang, that the strength of particle interactions is dictated by the symmetry of the theory. Since Wilczek finds the masses depending on the strength of forces, and Yang finds the strength of forces dictated by symmetry, the final result is to make mass a consequence of symmetry alone.

The last part of the book, with the title “Is Beauty Truth?,” is brief and speculative. It describes a grand unified theory of particle physics going far beyond the Core, introducing a whole menagerie of hypothetical particles that are sisters to the known particles, and a symmetry principle known as supersymmetry that interchanges each known particle with its sister. The word “interchange” here does not mean a physical replacement of one particle by another. It means the
mathematical interchange of the entire assemblage of known particles with the assemblage of their hypothetical sisters. The hypothesis of supersymmetry says that the equations describing the universe remain unchanged when all the known particles are interchanged with their unknown sisters. The interchange is a mathematical abstraction, not a physical action.

The grand unified theory is a bold venture into the unknown. It is a mathematical construction of spectacular beauty, unsupported by any experimental evidence. All that we can say for sure is that this theory is possibly true and certainly testable. Wilczek believes that the basic laws of nature must be beautiful, and therefore a theory that is beautiful has a good chance of being true. He believes that the grand unified theory is true because it is aesthetically pleasing. He points to several famous examples from the history of physics, when theories designed to be beautiful turned out to be true. The best-known examples are the Dirac wave equation for the electron and the Einstein theory of general relativity for gravity. If the grand unified theory turns out to be true, it will be another example of beauty lighting the way to truth.

At the end of the book, a chapter entitled “Anticipating a New Golden Age” describes Wilczek’s hopes for the future of particle physics. He sees the golden age starting very soon. His hopes are based on the Large Hadron Collider (LHC), the biggest and newest particle accelerator, built by the European Center for Nuclear Research (CERN) in Geneva. The LHC is a splendid machine, accelerating two beams of particles in opposite directions around a circular vacuum pipe that has a circumference of twenty-seven kilometers. Particle detectors surround the beams where they collide, so that the products of the collisions are detected. The energy of each accelerated particle will be more than seven times the energy of a particle in
any other accelerator. Wilczek confidently expects that supersymmetric sisters of known particles will be found among the debris from collisions in the LHC. By observing new particles and interactions in detail, he hopes to fill quickly the gaps in the grand unified theory.

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