by Neil Turok
THE MASSEY LECTURES SERIES
The Massey Lectures are co-sponsored by CBC Radio, House of Anansi Press, and Massey College in the University of Toronto. The series was created in honour of the Right Honourable Vincent Massey, former Governor General of Canada, and was inaugurated in 1961 to provide a forum on radio where major contemporary thinkers could address important issues of our time.
This book comprises the 2012 Massey Lectures, “The Universe Within: From Quantum to Cosmos,” broadcast in November 2012 as part of CBC Radio’s Ideas series. The producer of the series was Philip Coulter; the executive producer was Bernie Lucht.
NEIL TUROK
Neil Turok is one of the world’s leading theoretical physicists and a renowned educational innovator. Director of the Perimeter Institute for Theoretical Physics, he was formerly a professor of physics at Princeton and held a Chair of Mathematical Physics at Cambridge. As well as developing fundamental theories of the cosmos, he has led efforts to determine their predictions and to test them through observation. With Stephen Hawking, he developed the Hawking–Turok instanton solutions describing the birth of inflationary universes. With Paul Steinhardt, he developed a cyclic universe scenario, described in their critically acclaimed book Endless Universe: Beyond the Big Bang — Rewriting Cosmic History. In 1992, Turok was awarded the James Clerk Maxwell medal of the UK Institute of Physics and, in 2008, a prestigious TED Prize. Born in South Africa, Turok founded the African Institute for Mathematical Sciences (AIMS), a pan-African network of centres for education and research. This work has been recognized by awards from the World Summit on Innovation and Entrepreneurship (WSIE) and the World Innovation Summit on Education (WISE). Turok lives in Waterloo, Ontario, Canada.
ALSO BY NEIL TUROK
Endless Universe: Beyond the Big Bang —
Rewriting Cosmic History (with Paul J. Steinhardt)
THE UNIVERSE WITHIN
From Quantum to Cosmos
NEIL TUROK
Copyright © 2012 Neil Turok and Canadian Broadcasting Corporation
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Library and Archives Canada Cataloguing in Publication
Turok, Neil
The universe within : from quantum to cosmos / Neil Turok.
(CBC Massey lecture series)
Includes bibliographical references and index.
ISBN: 978-1-77089-225-5
1. Cosmology—Popular works. 2. Discoveries in science.
3. Research—Social aspects. I. Title. II. Series: CBC Massey
lecture series
QB982.T87 2012 523.1 C2012-902895-9
Library of Congress Control Number: 2012938339
ISBN: 978-1-77089-017-6 (US)
Cover design: Bill Douglas
Ccover images: (Brain) science picture co/science faction/Getty; (Universe) clearviewimages/iStockphoto
We acknowledge for their financial support of our publishing program
the Canada Council for the Arts, the Ontario Arts Council, and the Government of Canada through the Canada Book Fund.
To my parents
AUTHOR’S NOTE
IN THIS BOOK, I try to connect our progress towards discovering the physical basis of reality with our own character as human beings.
This is not an academic text. I describe some of physics’ biggest ideas and how they were discovered, but I make no serious attempt to provide a balanced history or to properly apportion credit. Instead, I use my personal experience as a common thread, along with accounts of people, times, and places that seem special to me. The personalities are interesting, but I use them mainly as illustrations of what is possible and of how much more capable we are than we realize. I am not a philosopher, historian, or an art or literary critic, but I draw on each of these subjects to illustrate the circumstances and the consequences of our deepening knowledge. This is a vast subject, and I apologize for my limited perspective and for my many arbitrary choices.
My goal is to celebrate our ability to understand the universe, to recognize it as something that can draw us together, and to contemplate what it might mean for our future.
I have benefitted from the insights and mentorship of wonderful colleagues, too numerous to mention. I have been equally inspired by many non-scientists, people who through their lives exemplify what it means to be human. Our science and our humanity are two sides of the same coin. Together, they are the means for us to live up to the opportunity of our existence.
ONE
MAGIC THAT WORKS
“Happy is the man who can recognize in the work of today a connected portion of the work of life,
and an embodiment of the work of Eternity.”
— James Clerk Maxwell1
WHEN I WAS THREE years old, my father was jailed for resisting the apartheid regime in South Africa. Shortly afterward, my mother was also jailed, for six months. During that time, I stayed with my grandmother, who was a Christian Scientist. My parents weren’t religious, so this was a whole new world to me. I enjoyed the singing, and especially the Bible: I loved the idea of a book that held the answer to everything. But I didn’t want a big Bible; I wanted a little Bible that I could carry around in my pocket.
So I campaigned endlessly for my grandmother to buy me the smallest possible Bible. When she finally did, I took it everywhere. I couldn’t read yet, but that didn’t matter to me. What I most wanted, even at that early age, was to capture and hold the truth, with the certainty and love that it brings.
My father was charged with sabotage and was fortunate to be released after only three and a half years. Others who had been tried on lesser charges were given life terms. On my father’s release from prison, he was held under house arrest but escaped and fled north to East Africa. We followed him there and lived in Tanzania for several years before moving to London, England. There we joined a small community of exiles trying to survive in unfamiliar, damp, and gloomy surroundings. Nevertheless, my parents always held firm to their ideas. “One day,” they told my brothers and me, “there will be a great change, and South Africa will be free.”
It was hard for us to believe them. Throughout the 1970s and 1980s, as I was growing up in England, going to high school and then university, the situation back home seemed hopeless. The apartheid regime was popular with the all-white electorate, and it had powerful allies overseas. South Africa even developed and tested nuclear weapons. The tiny handful of organized dissidents were easily captured and imprisoned. Protests by school students in Soweto were ruthlessly crushed, and the police state took an iron grip.
But then, quite suddenly, everything changed.
The apartheid system was founded on a profoundly wrong premise — that black people are inferior to white people — and this brought its demise. Within the country, the aspirations of the black majority could no longer be containe
d. External protests also gathered impact as more and more countries boycotted South Africa. In 1993, with Nelson Mandela’s negotiated release from prison, the mood turned. The white minority accepted that apartheid was no longer sustainable, and that the future would have to involve universal suffrage and greater opportunities for all. The change in South Africa was wrought by a simple but undeniable idea: justice — the principle of fairness, equity, and human rights that protects us all. Justice is a cause shared across races, cultures, and religions; it is powerful enough to win many people’s lifetime commitment and, for some, commitment of their lives. If you had to point to the driver of change in South Africa, it would be this one simple notion that prevailed over all the privilege, wealth, and weaponry that the apartheid regime amassed.
My parents were right. A good idea can change the world.
TODAY, WE LIVE IN a worried world that seems short of good ideas. We are confronted by challenges that can feel overwhelming: financial instability, overconsumption and pollution, energy and resource shortages, climate change, and growing inequality. All of these problems were created by humans, and they are all solvable. Yet we seem to be locked in a culture of short-term thinking, of the quick fix and the fast buck. Whereas what each of these problems really needs for its solution is consistent, principled, far-sighted actions extending over many years.
We’re reaching the limits of existing technologies and natural resources. We are in danger of losing our sense of optimism. Can we find smarter ways to manage our planet? Can we make the discoveries that will open up a bright future? Who are we, after all? Are we just the product of a process of random mutation and natural selection, now reaching its terminus? Or are we potentially the initiators of a new evolutionary stage, in which life may rise to a whole new level?
In these chapters, I want to talk about our ability to make sense of reality and to conceive of the universe within our minds. This ability has been a continuous source of powerful ideas, describing everything from the tiniest subatomic particle up to the entire visible cosmos. It has spawned every modern technology, from cellphones to satellites. It is by far and away our most precious possession, and yet it is also completely free to share. If history is anything to go by, the Universe Within us will be the key to our future.
It is not accidental that revolutions take place when they do. The greatest advances have occurred as a result of growing contradictions in our picture of reality that could not be resolved by any small change. Instead, it was necessary to step back, to look at the bigger picture and find a different way of describing the world and understanding its potential. Every time this happened, a whole new paradigm emerged, taking us forward to frontiers we had never previously imagined. Physics has changed the world, and human society, again and again.
The human mind holds these ideas in the balance: how we live together, who we are, and how we place ourselves within reality. Our conceptions greatly exceed any immediate need. It is almost as if the evolutionary process has an anticipatory element to it. Why did we evolve the capacity to understand things so remote from our experience, when they are seemingly useless to our survival? And where will these abilities take us in the future?
How did we first imagine the Higgs boson, and build a microscope — the Large Hadron Collider, capable of resolving distances a billionth the size of an atom — to find it? How did we discover the laws governing the cosmos, and how did we build satellites and telescopes that can see ten trillion times farther than the edge of the solar system, to confirm those laws in detail? I believe society can draw great optimism from physics’ phenomenal success. Likewise, physics can and should draw a greater sense of purpose from understanding its own origins, history, and connections to the interests of society.
What is coming is likely to be even more significant than any past transformation. We have already seen how mobile communications and the World Wide Web are opening up global society, providing information and education on a scale vastly larger than ever before. And this is only the beginning of how our new technologies will change us. So far, our scientific progress has been founded on, but also limited by, our own physical nature. We are only able to comprehend the world in a classical picture. This has been an essential stepping stone in our development, but one that we need to move beyond. As our technological capabilities grow, they will drastically extend our abilities, our experience of the world, and, in time, who we are.
The internet is only a harbinger. Quantum technologies may change entirely the way in which we process information. In time, they may do much more, allowing us to gain a heightened awareness of reality and of the ways the physical world works. As the depth of our knowledge grows, our representations of the universe will achieve much higher fidelity. Our new knowledge will enable technologies that will vastly supercede current limits. They may change our very nature and bring us closer to realizing the full potential of our existence.
As we look ahead our goal should be to experience, to understand, and to be a part of the universe’s development. We are not merely its accidental byproducts; we are the leading edge of its evolution. Our ability to explain the world is fundamental to who we are, and to our future. Science and society’s mission should be one and the same.
Engraved on Karl Marx’s tombstone are these famous words: “The philosophers have only interpreted the world, in various ways. The point, however, is to change it.” Riffing on a quote attributed to Gandhi, I would say, “The point, however, is to be the change.”
· · ·
I HAVE BEEN FORTUNATE to spend some of my life in Africa, the cradle of humanity. One of my most memorable experiences was visiting the Ngorongoro Crater, the Serengeti, and the Olduvai Gorge, which early human ancestors inhabited nearly two million years ago. There is an abundance of wild animals — lions, hyenas, elephants, water buffalo. Even the baboons are dangerous: a large male weighs nearly a hundred pounds and has enormous incisors. Nevertheless, they are all afraid of humans. If you are camping there and a big baboon tries to steal your food, all you have to do is raise your arm with a stone in your hand, and it will scurry away.
As puny as human beings are, our ancestors acquired dominance over the rest of the animal kingdom. With their new modes of behaviour, standing up and throwing stones, using tools, making fires, and building settlements, they outsmarted and out-psyched all the other creatures. I have seen elephants and water buffalo move away at merely the scent of a lone Maasai approaching, strolling unconcernedly through the bush with his hand-held spear, as if he were the king of it all. Our mastery of nature began with our ancestors in Africa, and they deserve our utmost respect.
From the invention of tools and then agriculture, the next great leap forward in technology may have been the development of mathematics: counting, geometry, and other ways of understanding regularities in the world around us. Many of the oldest mathematical artifacts are African. The oldest is a baboon’s leg bone, from a cave in Swaziland, dated to 35,000 B.C. It has twenty-nine notches on it, perhaps marking the days of a lunar cycle. The second oldest is another baboon’s leg bone found in the eastern Congo and dating from around 20,000 B.C. It is covered in marks grouped in a manner suggestive of simple arithmetic. The oldest known astronomical observatory is a stone circle at Nabta Playa, in southern Egypt near the border with Sudan, built around 4000 B.C. Then, of course, there are the great pyramids built in Egypt, from around 3000 B.C. onwards. Mathematics allowed people to reliably model the world, to make plans, and to predict outcomes.
As far as we know (no written records survive), the idea that mathematics could reveal powerful truths about the universe originated with Pythagoras and his followers in ancient Greece in the sixth century B.C. They invented the word “mathematics” (the Pythagoreans were called the mathematici) and the notion of a mathematical “proof”: a set of logical arguments so compelling as to make the result unquestionable. The Pythagorean theorem — that th
e area of a square drawn on the long side of a right-angled triangle equals the combined area of the squares drawn on the two shorter sides — is the most famous such proof. (However, the fact it proves was known much earlier: for example, it is referred to on tablets used for surveyors’ calculations dating from around 1800 B.C. in ancient Babylon, near modern Baghdad.)
The Pythagoreans formed a religious cult, based near Croton, in southern Italy, with a focus on mathematics’ mystical power. One of their accomplishments was to understand the mathematical nature of music. Dividing a plucked string into halves produced an octave, into thirds a fifth above that octave, and into quarters another fourth above that. If mathematics could so neatly account for musical harmonies, they reasoned, it might explain many other aspects of order in the universe. Building on earlier ideas of Anaximander, who some consider to have been the first scientist and was, perhaps, Pythagoras’s teacher, the Pythagoreans attempted to “construct the whole heavens out of numbers.”2 This insight, two millennia before Newton, was to become the foundation for all of physics.
The Pythagoreans apparently gave good advice to Croton’s rulers — for example, on introducing a constitution — which helped the town’s economy prosper. But they were also perceived as elitist and obsessively secretive. In the words of one historian, “Their assumption of superiority and esoteric knowledge must at times have been hard to bear.”3 This probably contributed to the Pythagoreans’ tragic downfall, in which, according to some versions, Pythagoras was killed. The Pythagoreans’ untimely demise was an early signal of the dangers of the separation of scientists from everyday society.
The division has reappeared, again and again. For example, in medieval Europe, the university bachelor’s curriculum was dominated by Latin, logic, and rhetoric (the trivium), the skills which were needed for diplomacy, government, and public presentation. Those who continued to their master’s would take arithmetic, music, geometry, and astronomy (the quadrivium). The separation between non-scientists and scientists was inevitable, as human knowledge expanded and expertise became more and more specialized. It led to a division between the sciences and the arts and humanities, which the English physicist and author C. P. Snow famously referred to as the “Two Cultures.” This seems to me unfortunate. Isn’t science also an art? And shouldn’t scientists also have humanity?