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ESCAPE FROM THE JUNGLE OF NO IMAGINATION

Into blinding darkness enter

Those who worship ignorance

Into as if still greater darkness

Enter those who delight in knowledge

—THE UPANISHADS

We physicists have determined that over 95 percent of the matter and energy in the universe is invisible. We have branded this enigmatic stuff dark matter and dark energy; their discovery raised puzzles that shook the foundations of physical law. The gravitational effects of dark matter are observed in large halos surrounding galaxies and are critical to our current conception of how the large-scale arrangement of visible matter in the universe came to be. Likewise, so far, with dark energy, which was discovered with telescopes by measuring the accelerated expansion of the universe, it too has been the province of cosmologists, who have written about it only in reference to extraterrestrial matters and the overall shape and destiny of the universe. This is a mistake. This dark stuff turns out to play a hidden role in the visible world, including in our understanding of life itself. Dark energy resides in all empty space, not just outer space, and permeates all existence. Its quantum effects are present even in the spaces between the very atoms in our bodies. The time has come for a new Newton, to reunite the physics of the extraterrestrial with the physics of the terrestrial. Such an integration might facilitate our understanding of dark matter and dark energy, enabling a better understanding of who we are and of the cosmos in which we live.

Just as the discoveries of dark matter and dark energy shook the foundations of physics, our continued inability to unearth the identity and nature of most of the universe continues to shake them, and, consequently, it limits our understanding of our place in the universe. We still do not know much about the dark sector except that it exists; yet researchers often ascribe properties to dark matter based on presumptions that mimic known physics and are not intrepid enough. It seems to me that methodologies that might enable us to ask new questions, and find new properties or new roles for the dark in our universe, generate fear. Do we dread the dark so much that we project our fears onto the very phenomena about which we are scientifically ignorant?

Dark matter and dark energy are not the only anomalies our current physics doesn’t handle. A handful of other deviations from our accepted theories of physics generate speculations that likewise trouble physics. The resolution of these anomalies may shake the foundation of what we presume to be true.

Such anomalies raise a related set of questions, one more apropos for the social sciences than the natural sciences: How does science respond to ideas that might violate our scientific norms and expectations? Does the scientific community fear embracing “dark” ideas from outsiders, especially if the ideas may not be in a form that the community is comfortable with, if they do not fit seamlessly into our theories and expected practices?

At the turn of the last century, the discovery of black-body radiation found in most objects that appeared to not emit light was a theoretical “catastrophe” for classical physics, giving nonsensical predictions that are not seen in experiments. But when German physicist Max Planck embraced the reality of the black body, he turned electromagnetic theory on its head, and the quantum revolution was born. Is it possible that the theoretical anomalies we now confront will yield a comparable scientific revolution? If so, who is likely to motivate it?

Regardless of our ability to create the most abstract mathematics and come to know truths beyond our five senses, as humans we are limited by our social and psychological conditioning. In this book, we will go beyond the current conceptual and scientific-sociological paradigm into uncharted and sometimes risky conceptual territories. What lurks beyond the black hole singularity in our galaxy and before time existed at the big bang? How did cosmic structure emerge from a chaotic and featureless evolving early universe? What is the role of dark energy and dark matter in the universe? Is there a hidden link between the emergence of life and the laws of physics? These are questions on the boundary of what we know; answering them may call into question the theories that constitute our knowledge. If we are to answer them, we must ask whether the scientific community is able to incorporate into its activities nontraditional members, outsiders more likely to see beyond our current theoretical horizon; further, is the scientific community, as it is now structured, able to empower these outsiders to break new ground?

I want to bring you with me as I try to take on some of these questions. To do this effectively, I will provide both the necessary background and the conceptual tools needed to understand a bit of established physics. My discussion is based on three fundamental principles that underlie all known physics; a grasp of them will enable us to understand some of the problems at the borders of what physicists think they know and understand. I will be frank, sometimes controversial, and deliberately engage in some of my own wild speculations. This is not just a book about what we know in physics, but a book that explicates the frontiers of physics, a book about how physics is done.

Much that is taught and written about physics expresses what we know already. This book presumes that the process of doing physics is different than the process of learning the physics we know already. The first explores what we do not yet know, while the second transmits what others have learned previously. Here, while some of the latter is necessary—there are certain things that must be shared—our focus is on how we might think about what we do not yet know.

Crucial is a simple insight: a responsibility of physicists is to apply what we know already in new areas of inquiry, to transform and extend our knowledge. Great teaching in physics helps us to do physics, not simply learn the physics we know already. This means learning physics has to enable us to work at the boundary of what we know or, in rare cases, to go beyond those boundaries, or even reconstruct the very framework of our knowledge. If this book is successful, it will help you understand what it means to be creative in theoretical physics.

Often when I am stuck on a problem—of the physics variety or the personal one—I make a pilgrimage to the northern coast of my birthplace, Trinidad and Tobago. There is something that feels unspeakably out of body about trekking through the lush sixty-mile stretch of the deep green mountain range overlooking Las Cuevas Bay. I hike up the winding paths to the top of a hill overlooking the ocean, the tropical jungle sounds looming behind me and the rhythmic crashing of the crystalline emerald crescent waves sounding below. Surrounded by nature, beautiful and primordial, I am often surprised to find new insights into my problems.

One day not so long ago, I found myself getting nowhere on a research problem. I headed back to the jungle to look at the sea. While I was there it dawned on me—not the solution to the research problem, but the realization that during two decades of scientific research, I had been unconsciously dodging my original reason for becoming a physicist: to make a meaningful scientific discovery. I realized I feared failure and the professional risk failure entailed. The ability to maintain a scientific career is driven by, among other factors, your reputation among your peers and familiarity with your work. Penalties await those who are perceived as a “crackpot” or who speculate too much. I knew that some of the ideas that interested me, such as the connection between consciousness and quantum mechanics, would make me vulnerable to stigma and potentially stump my career.

In theoretical physics research, there is a sense of dissatisfaction, a belief that we have not been able to break new ground in the same way that led to the quantum and relativity revolutions early last century. It’s not to say that people aren’t trying to address their dissatisfactions; a handful of papers are posted every day on an online global archive of physics research called the Archives, and oftentimes these papers offer new approaches to unsolved mysteries. Despite this, there’s not much feeling of progress. Why is this? Is it because these problems are too hard for us? Or is it that in the search for the truth, some scientists are afraid to look at uncharted or forbidden territories, afraid because there may be penalties, reputational and professional, for stepping outside accepted paradigms? I think that it’s the latter. In this book, I will provide my thoughts and reflections; I will take some risks, hoping that we learn something significant along the way, whether I am right or wrong.

As a Black physicist, this potential strength—that I am brimming with ideas, my capacity to generate speculative thinking—can be an impediment. Black persons in scientific circles are often met with skepticism about their intellectual capabilities, their ability to “think like a physicist.” Consequently, my exploratory, personal style of theorizing, when coupled with my race, often creates situations where my white colleagues become suspicious and devalue my speculations. I have navigated a career in physics in spite of these racial and sociological prejudices, and, given both my personality and my predilections, I continue to march ahead, sharing my conjectures, which, at least sometimes, are theoretically fruitful. This book will be no exception.

During my time of self-reckoning in Trinidad, I decided to devote the majority of my research efforts to working on some of the big mysteries in physics. To do so effectively, I would have to bring my entire being to how I do physics, which meant engaging in improvisational and wild speculations. When you meet me in person, it is clear that I am volcanic with ideas, most of which turn out to be wrong, while some, even among those that are “wrong,” are fruitful and worth pursuing. Underlying these ideas is a latent foundation, the theoretical and technical tools of my trade.

Physics is a social activity, and like all social activities it is regulated by norms. Practitioners are expected to conform to these normative expectations, and they are sanctioned negatively when they violate them. Too often the expectations of what it means to do “good science” become confused with specific theoretical orientations, which means that practitioners in subdisciplines are expected to uphold specific theoretical arguments. This is desirable insofar as it rules out ideas like flat-earthism and others that make no sense scientifically. Sometimes, however, this expectation of conformity stifles innovation and progress. Some scientists are reluctant to explore ideas outside the expected paradigm because they will be punished if they do so, which means that paradigm-shattering theories can be inhibited from emerging.

We need to distinguish clearly between the values and norms that regulate scientific activity and those that demand conformity to a particular body of theory, a particular paradigm, within a scientific community. Both are constituted socially, but the latter obligations can restrict our creativity, our ability to constitute new theoretical orientations. It is crucial, however, to recognize that our theoretical arguments must be regulated within and evaluated through the application of scientific values, the values of cognitive rationality. Very simply, this means that our theoretical arguments must be logically coherent and empirically warrantable. Not every “creative idea” may be turned into viable physical theory. In fact, the likelihood that any one of us will create a new paradigm because we have violated the norms regulating activity within the standard paradigm is very slim. No one can do so, however, without violating these norms.

I want this book to serve as a source of inspiration and encouragement for individuals who feel disenfranchised and unwelcome in our scientific communities, people who are sometimes, or often, made to feel that they are not valued as contributors to the scientific endeavor. So as much as this is a book about my reflections on the state of physics, as theory, I also reflect on and analyze both the sociology of science and my own experiences to argue for the efficacy of outsiders’ presence and perspectives in scientific communities and inquiry. The path to becoming a scientist poses challenges for everyone. In shedding new light on the social dynamics of science, and simply sharing our stories, we can see how some of the challenges outsiders face can inspire them to make significant scientific contributions. I hope to convince my readers that diversity in science is not simply a social justice concern, but that it enhances the quality of the science we accomplish.

Many of the theoretical physicists of my generation were inspired by the golden era in the first half of the twentieth century, when the likes of Albert Einstein, Richard Feynman, Paul Dirac, Emmy Noether, and Wolfgang Pauli, to name only a few of our idols, gave birth to quantum field theory and general relativity. These theories have been spectacularly confirmed, and they are responsible for most of our modern technology.

One of the essential tools that Einstein and Erwin Schrödinger employed in discovering the equations and fundamental laws of relativity and quantum physics was “thought experiments”: mental visualizations, or imaginations of physical happenings that are impossible to carry out in terrestrial settings or with current experimental techniques. Some of the famous ones include Schrödinger’s cat and Einstein’s vision of riding on a beam of light. These visualizations, when articulated as mathematical equations, led to solutions that predict the behavior of the semiconductor devices that drive powerful computers, including the smartphones that are part of our everyday lives.

When I first learned how the greats managed to make these discoveries, it seemed as if some mental wizardry were at work, a wizardry that has been overlooked by my generation and our teachers. Theoretical physics has grown to become extremely mathematical, and while mathematics is a necessary and powerful tool, I realized that if I were to have a shot at making an important discovery, I would have to find my way to acquire a bit of that wizardry, the intuitions leading to the theoretical insights that lead to mathematical equations (intuitions not derivative from those equations).

As a young student taking introductory courses in physics, I had the impression that physics was a jungle of countless equations and intricate theories. The task, or so it seemed, was to digest and apply them. Even decades later, as a researcher in theoretical physics, it dawned on me that my colleagues and I were lost in that same jungle. The mentality required to work through problem sets made the handful of problems in cosmology and particle physics that seemed important also seem insurmountable. We did not even know the right questions to ask.

At Las Cuevas Bay, after gazing at the waves for some time, I had an epiphany: Who better to help us address our questions than Einstein himself? What if we had a bird’s-eye view of the jungle of physics from which we could see the origins of the theories and the interconnections between the laws that give rise to (and constrain) them? Would this perspective facilitate our attempts at reworking these theories to better address our contemporary questions? Could we turn from calculating, boring physicists to brave adventurers, imagining worlds no one else had seen before?

During my time as a postdoctoral researcher in theoretical physics at the Stanford Linear Accelerator Center (SLAC), I received a surprising letter from the National Geographic Society. I wondered if I owed them a payment. Instead, the letter congratulated me on being selected as a National Geographic Emerging Explorer. I was both elated and confused. I had never applied to be an explorer, nor did I think of myself as one. When it turned out that it was not, in fact, a mistake, I was deeply honored and did not say no to the monetary prize and subsequent trips to National Geographic headquarters to meet other explorers I admired. For example, I had always wanted to meet ethnobotanist Wade Davis, whose book was the basis for one of my favorite horror movies, The Serpent and the Rainbow.

All explorers were invited to a fundraiser and to celebrate the seventieth birthday of the Society’s president at the time, Gil Grosvenor. There were many impressive people there, and I quickly started to feel a little out of place. Among the newly elected explorers was an underwater cave diver who could contort his body to fit into intricate caves for hours, hundreds of feet under the ocean. There was a woman who lived among lions in the Serengeti, and a man who explored and lived in Antarctica for extended periods. At the fundraiser, each explorer was placed at a dinner table with a group of potential donors, to entertain them. After we introduced ourselves, one disappointed donor said to me, “You don’t hang out in the jungle? You don’t fly airplanes? Why did they make a theoretical physicist an explorer?!”

I didn’t want the donor to feel duped. So as a good spokesperson for National Geographic, I responded with conviction: “I explore the cosmos with my mind.” I went on to explain how the worlds that cosmologists explore are even more extreme than explorers on Earth, so extreme that we are forced to explore them in our imaginations. I went on to explain that Einstein explored the nature of space-time, and this led to the ultimate prediction and discovery of a supermassive black hole at the center of our galaxy. Try exploring that physically! Some donors were interested, but others wanted to hang out with a “real” explorer.

Despite the drama, that night got me thinking about the similarities between physical and mental exploration, about the extreme places theoretical physicists must explore to make progress. These mental explorations are the fuel for discovering and clarifying physical theories; they are the domain of Einstein’s notion of principle theories.

In 1914, soon after his revolutionary discoveries in quantum mechanics and relativity, Einstein gave an address to the Prussian Academy of Sciences in which he discussed his strategy for discovery in theoretical physics. “The theorist’s method involves his using as his foundation general principles from which he can deduce conclusions,” Einstein said. “His work thus falls into two parts. He must first discover his principles and then draw the conclusions which follow from them.”

Einstein could perceive a hidden reality, where time and space could slow down, speed up, bend, and even cease to exist, a reality that transcends the limits of our daily perceptions, a reality that makes no sense to us when we are thinking commonsensically. Surely there are still new levels of reality that are hidden, and like Einstein we ought to be curious to know what lies beyond our current (commonsensical) understanding in physics.

As a student, I had mistakenly thought that physics was driven mostly by mathematics and logical reasoning. Einstein’s conviction was that principles are the driving force behind new discoveries, while mathematics is necessary to make physics precise, to inform the clarification of the principles, to explain and clarify our characterizations of how we conceptualize phenomena, and to make predictions. In short, math is not enough; it is a tool. The important question is how does one come up with new principles? Einstein answers: “Here there is no method capable of being learned and systematically applied so that it leads to a new [principle]. The scientist has to worm these principles out of nature by perceiving in comprehensive complexes of empirical facts certain general features which permit of precise formulation.”

He was saying that a scientist should make connections and see patterns across a range of experimental outcomes, which may not be related to each other in an obvious way. Once the scientist ekes out these patterns, she makes a judgment call as to whether a new principle of nature is necessary. But this is misleading. Facts are statements about phenomena, but they don’t exist on their own; they are always conceptualized, which means that they are, if only implicitly, constructed theoretically. Experiments allow us to answer theoretically constructed questions. Theory tells us what “facts” to look for.

As an adolescent Einstein was free to play in his father’s electrical company in Pavia, Italy. This play fertilized his imagination; it enabled him to envisage what he would experience if he could catch up to a light wave. His process of “worming” out these principles entails visualizing phenomena that are not directly accessible to our senses or current experiments. It eventually enabled him to formulate theories that told us what we would find and helped us to understand where we might look to find it.

How did Einstein know when to postulate his theory of relativity? How, aside from his natural-born genius, was he able to arrive at his principles? I found part of the answer in a lecture he gave at Oxford University in 1933. “[The discovery of principles] are free inventions of the human intellect, which cannot be justified either by the nature of that intellect or in any other fashion a priori,” he said. But what does Einstein mean by this? Sometimes to get around a scientific problem, one must consider possibilities that defy the rules of the game. If you don’t enable your mind to freely create sometimes strange and uncomfortable new ideas, no matter how absurd they seem, no matter how others view your arguments or punish you for making them, you may miss the solution to the problem. Of course, to do this successfully, it is important to have the necessary technical tools to turn the strange idea into a determinate theory.

When I told the donors at National Geographic that I explored the cosmos with my mind, I wasn’t jiving. Those theoretical physicists who explored with their intellect, making “free inventions,” sounded to me like masters of improvisation. Einstein gave me the hall pass to continue my free inventions. But, like Einstein did, we must first look to the fundamental principles underlying modern physics and use them to explore some of the big mysteries physicists face. In the pages that follow, we will engage in free inventions, trying to cook up some new physics while journeying through some of the biggest mysteries at the frontiers of cosmology and fundamental physics. While some of the ideas presented in this book are debatable and speculative, I hope that it nonetheless provides not only insight into how a theoretical physicist dreams up new ideas and sharpens them into a consistent framework but also, perhaps, the inspiration to think of your own big ideas.