Fundamentals: Ten Keys to Reality

Book Preface

I
This is a book about fundamental lessons we can learn from the study of the physical world. I’ve met many people who are curious about the physical world and eager to learn what modern physics says about it. They might be lawyers, doctors, artists, students, teachers, parents, or simply curious people. They have intelligence, but not knowledge. Here I’ve tried to convey the central messages of modern physics as simply as possible, while not compromising accuracy. I’ve kept my curious friends and their questions constantly in mind while writing the book.
To me, those fundamental lessons include much more than bare facts about how the physical world works. Those facts are both powerful and strangely beautiful, to be sure. But the style of thought that allowed us to discover them is a great achievement, too. And it’s important to consider what those fundamentals suggest about how we humans fit into the big picture.
II
I’ve selected ten broad principles as my fundamentals. Each forms the theme of one chapter. In the body of each chapter, I explain and document that chapter’s theme from different perspectives, and then make some informed guesses about its future development. Those informed guesses were fun to create, and I hope they’re exciting to read. They are meant to convey another fundamental message: that our understanding of the physical world is still growing and changing. It is a living thing.

I’ve been careful to separate speculations from facts and, for the facts, to indicate the nature of the observations and experiments that establish them. For perhaps the most fundamental message of all is that we do understand many aspects of the physical world very deeply. As Albert Einstein put it, “The fact that [the universe] is comprehensible is a miracle.” That, too, was a hard-won discovery.
Precisely because it is so surprising, the comprehensibility of the physical universe must be demonstrated, not assumed. The most convincing proof is that our understanding, though incomplete, has let us accomplish great and amazing things.
In my research, I try to fill gaps in our understanding and to design new experiments to push the frontiers of possibility. It’s been a joy for me, in writing this book, to step back and reflect, wonderstruck, on some highlights of what generations of scientists and engineers, cooperating across time and space, have already accomplished.
III
Fundamentals is meant, as well, to offer an alternative to traditional religious fundamentalism. It takes up some of the same basic questions, but addresses them by consulting physical reality, rather than texts or traditions.
Many of my scientific heroes—Galileo Galilei, Johannes Kepler, Isaac Newton, Michael Faraday, James Clerk Maxwell—were devout Christians.(In this they were representative of their times and surroundings.) They thought that they could approach and honor God by studying His work. Einstein, though he was not religious in a conventional sense, had a similar attitude. He often referred to God (or “the Old One”), as he did in one of his most famous quotations: “Subtle is the lord, but malicious he is not.”
The spirit of their enterprise, and mine here, transcends specific dogmas, whether religious or antireligious. I like to state it this way: In studying how the world works, we are studying how God works, and thereby learning what God is. In that spirit, we can interpret the search for knowledge as a form of worship, and our discoveries as revelations.

IV

Writing this book changed my perception of the world. Fundamentals began as an exposition but grew into a contemplation. As I reflected on the material, two overarching themes emerged unexpectedly. Their clarity and depth have astonished me.
The first of those themes is abundance. The world is large. Of course, a good look at the sky on a clear night is enough to show you that there’s lots of space “out there.” When, after more careful study, we put numbers to that size, our minds are properly boggled. But the largeness of space is only one aspect of Nature’s abundance, and it is not the one most central to human experience.
For one thing, as Richard Feynman put it, “there’s plenty of room at the bottom.” Each of our human bodies contains far more atoms than there are stars in the visible universe, and our brains contain about as many neurons as there are stars in our galaxy. The universe within is a worthy complement to the universe beyond.
As for space, so also for time. Cosmic time is abundant. The quantity of time reaching back to the big bang dwarfs a human lifetime. And yet, as we’ll discuss, a full human lifetime contains far more moments of consciousness than universal history contains human lifespans. We are gifted with an abundance of inner time.
The physical world is abundant, as well, in hitherto untapped resources for creation and perception. Science reveals that the nearby world contains, in known and accessible forms, far more energy and usable material than humans presently exploit. This realization empowers us and should whet our ambitions.
Our unaided perception brings in only a few slivers of the reality that scientific investigation reveals. Consider, for example, vision. Our sense of vision is our widest and most important portal to the external world. But it leaves so much unseen! Telescopes and microscopes reveal vast treasure troves of information, encoded in light, that ordinarily come to our eyes unrecognized. Moreover, our vision is limited to one octave—the span of visible light—from an infinite keyboard of electromagnetic radiation, which runs from radio waves to microwaves to infrared on one side, and from ultraviolet to x-rays and gamma rays on the other. And even within our one octave, our color vision is blurry. While our senses fail to perceive many aspects of reality, our minds allow us to transcend our natural limits. It is a great, continuing adventure to widen the doors of perception.
V
The second theme is that to appreciate the physical universe properly one must be “born again.”
As I was fleshing out the text of this book, my grandson Luke was born. During the drafting, I got to observe the first few months of his life. I saw how he studied his own hands, wide-eyed, and began to realize that he controlled them. I saw the joy with which he learned to reach out and grasp objects in the external world. I watched him experiment with objects, dropping them and searching for them, and repeating himself (and repeating himself . . .), as if not quite certain of the result, but laughing in joy when he found them.
In these and many other ways, I could see that Luke was constructing a model of the world. He approached it with insatiable curiosity and few preconceptions. By interacting with the world, he learned the things that nearly all human adults take for granted, such as that the world divides into self and not-self, that thoughts can control movements of self but not of not-self, and that we can look at bodies without changing their properties.
Babies are like little scientists, making experiments and drawing conclusions. But the experiments they do are, by the standards of modern science, quite crude. Babies work without telescopes, microscopes, spectroscopes, magnetometers, particle accelerators, atomic clocks, or any other of the instruments we use to construct our truest, most accurate world-models. Their experience is limited to a small range of temperatures; they are immersed in an atmosphere with a very special chemical composition and pressure; Earth’s gravity pulls them (and everything in their environment) down, while Earth’s surface supports them . . . and so forth.
Babies construct a world-model that accounts for what they experience within the bounds of their perception and environment. For practical purposes, that’s the right plan. To cope with the everyday world, it is efficient, and reasonable, when we are children, to take lessons from the everyday world.

But modern science reveals a physical world very different from the model we construct as babies. If we once again open ourselves up to the world, curious and without preconceptions— if we allow ourselves to be born again—we come to understand the world differently.
Some things, we must learn. The world is built from a few basic
building blocks, which follow strict but strange and unfamiliar rules.
Some things, we must unlearn.
Quantum mechanics reveals that you cannot observe something without changing it, after all. Each person receives unique messages from the external world. Imagine that you and a friend sit together in a very dark room, observing a dim light. Make the light very, very dim, say, by covering it with layers of cloth. Eventually, both you and your friend will see only intermittent flashes. But you will see flashes at different times. The light has broken up into individual quanta, and quanta cannot be shared. At this fundamental level, we experience separate worlds.
Psychophysics reveals that consciousness does not direct most actions, but instead processes reports of them, from unconscious units that do the work. Using a technique known as transcranial magnetic stimulation
(TMS), it is possible to stimulate the left or right brain motor centers in a subject’s brain, at the experimenter’s discretion. A properly sculpted TMS signal to the right motor center will cause a twitch of the left wrist, while a properly sculpted TMS signal to the left motor center will cause a twitch of the right wrist. Alvaro Pascual-Leone used this technique ingeniously in a simple experiment that has profound implications. He asked subjects, upon receiving a cue, to decide whether they wanted to twitch their right or their left wrist. Then they were instructed to act out their intention upon receiving an additional cue. The subjects were in a brain scanner, so the experimenter could watch their motor areas preparing the twitch. If they had decided to twitch their right wrist, their left motor area was active; if they decided to twitch their left wrist, their right motor area was active. It was possible, in this way, to predict what choice had been made before any motion occurred.
Now comes a revealing twist. Occasionally Pascual-Leone would apply a TMS signal to contradict (and, it turns out, override) the subject’s choice. The subject’s twitch would then be the one that TMS imposed, rather than the one he or she originally chose. The remarkable thing is how the subjects explained what had happened. They did not report that some external force had possessed them. Rather, they said, “I changed my mind.”
Detailed study of matter reveals that our body and our brain—the physical platform of our “self”—is, against all intuition, built from the same stuff as “not-self,” and appears to be continuous with it.
In our rush to make sense of things, as infants, we learn to misunderstand the world, and ourselves. There’s a lot to unlearn, as well as a lot to learn, on the voyage to deep understanding.
VI
The process of being born again can be disorienting. But, like a roller-coaster ride, it can also be exhilarating. And it brings this gift: To those who are born again, in the way of science, the world comes to seem fresh, lucid, and wonderfully abundant. They come to live out William Blake’s vision: