INTRODUCTION

Old Man Gets More Befuddled

It was the fall of 2019, the pre-plague era, when my friend Robert Hutchinson asked me and my son Mac to trek with him through Namibia’s Fish River Canyon. Robert, a noble beast of a man, had been diagnosed with liver cancer, and he wanted to embark on one last adventure before it was too late. We planned to go the following spring, after my semester ended. The coronavirus dashed our plans, and so on May 17, 2020, I finished posting final grades for my three classes in a foul mood, cursing fate and wondering what to do on my summer break. I needed a project, something to distract me from the pandemic and the horror show of American politics.

Glancing at Facebook, I noticed that Sabine Hossenfelder, an iconoclastic physicist I’d recently brought to my school to give a talk, had released a video on quantum mechanics. She promised that in ten minutes, with a little “simple” math, she would explain the difference between superposition and entanglement. Great, I thought, these quintessential quantum concepts have always puzzled me. But when I watched Sabine’s video, I didn’t get the math or technical terms. I felt dumb, as always when I try to grasp quantum mechanics.

Sabine Hossenfelder and me in Hoboken, New Jersey, in 2018. This book is kind of her fault.

Although I live and teach in Hoboken, New Jersey, I happened to be in New York City at the apartment of my girlfriend. I’ll call her Emily. Sensing my sour mood, she urged me to read a book she’d just finished: Big Magic: Creative Living Beyond Fear, by Elizabeth Gilbert. Normally, I shun self-help books. But Emily had just complained about my tendency to dismiss her advice, so I grudgingly opened Big Magic. To my surprise, the book absorbed me. Gilbert, a bestselling author, struggles like the rest of us. Curiosity is her most reliable means of overcoming fear and pain. She is happiest when curiosity transports her outside herself, and she becomes absorbed in learning something new.

Yeah, I thought, that’s what I need, to learn something new, something hard. But what? Immediately the answer came: I should learn quantum mechanics, really learn it, the way physicists learn it, with the math. The more I thought about this possibility, the more excited I got. Imagine how cool it would be to watch Sabine’s videos and know what she’s talking about! And hey, maybe I can get a book out of this!

I decided to run my idea by Emily. She is a veteran of the book-publishing racket, and she’s a hard-ass. She rejects most of my book ideas as non-commercial and dumb, which to her amount to the same thing. I felt nervous as I entered her bedroom, where she was lying on the bed studying a book on herbal remedies. As I explained my idea to her, emphasizing that it had been inspired by Big Magic, Emily nodded. This sounded like a fun pandemic project, and books in this genre—old guy learns Greek or guitar or some other new trick—can do well. [1]

Thrilled by her positive response, I began excitedly chattering about superposition, entanglement and other topics I hoped to master. Emily asked if she would have to listen to me blathering about physics for the next year; she hoped not (in vain, as it turned out). As she resumed reading her book, I thanked her for her encouragement and returned to the living room. I opened a notebook and began jotting down a plan of action for what I came to call my quantum experiment. This book covers the experiment’s first 18 months.

Why Quantum Mechanics?

Quantum mechanics is a contradiction, an embarrassment, really, lurking at the heart of modern knowledge. It is, on the one hand, a fantastically successful mathematical model of matter in motion. Since its inception in the early 20th century, quantum mechanics has evolved into a clade of theories describing events at the smallest and biggest scales, from the swerve of an electron to the outrush of the cosmos. These advances emboldened physicists to seek a unified theory, also called a final theory or theory of everything, that tells us how the universe, and hence we, came to be.

Quantum physics has supercharged chemistry and material science, and it has spawned gadgets that have transformed our lives, from hydrogen bombs to computer chips. Governments and companies are now funneling billions of dollars into quantum computing, which seeks to harness superposition and entanglement—those same confounding effects that Sabine Hossenfelder promised to teach me in ten minutes—to produce machines with unprecedented power.

And yet quantum mechanics makes no sense. It upends our basic assumptions about what is real and what is knowable. It challenges science’s axiomatic premise, that through meticulous investigations we can arrive at an objective understanding of nature. Experts keep trying to interpret the theory, to say what it means, but their conclusions are wildly divergent. Meanwhile, quantum quacks claim the theory corroborates their pseudo-scientific, pseudo-medical, pseudo-mystical claims. “Quantum” has become a pop-culture meme, a marketing cliché, which connotes something that seems like magic but is super-scientific and beyond your comprehension.

In my decades as a science writer, I have often reported on physics, and especially on the search for a unified theory, which thrilled me when I first learned about it. By the mid-1990s, I’d decided that unified theories are just science fiction with equations, because they cannot be experimentally tested. And all unified theories are quantum theories, which pose the same paradoxes as plain old quantum mechanics. Physicists’ quest for a final revelation, which solves the riddle of reality, is a dead end. So I argued in my book The End of Science.

Although I hated admitting it, I often felt uneasy about being so judgmental. Who the hell am I to have opinions on physics? I majored in literature before going to graduate school in journalism. I rely on experts to translate their technical knowledge into terms I can understand. I occasionally toyed with the idea of studying real physics, with the math, but never seriously. That would be too hard and take too long, and I had too many deadlines to meet, not to mention my duties as a husband and father. Those were my excuses when I was a full-time science writer.

In 2005 I got a job teaching humanities courses (including science writing) at Stevens Institute of Technology in Hoboken. This gig pays the bills and leaves me with plenty of time to indulge my obsessions. I’m also divorced, my children grown and on their own. Emily and I, who met in 2009 after my marriage collapsed, keep separate apartments and value our time apart. The illness of my friend Robert, not to mention the Covid pandemic, also had me dwelling on life’s ephemerality. All of this is to say that the time was right in May 2020 for me to learn quantum mechanics—or to try, before it was too late.

A note on nomenclature: Although I might say quantum physics or quantum theory now and then, I prefer quantum mechanics for two reasons. First, that phrase refers to the theory invented in the last century to account for experiments on matter and electromagnetism. That original, bare-bones theory, which excludes the effects of relativity, is my focus; but all the later, fancier quantum theories—including candidates for a theory of everything--share its puzzling features.

Second, I like the oxymoronic ring of quantum mechanics. Mechanics sounds clunky, old fashioned, steam-punky, evoking pistons, sprockets, gears, a rigid determinism; whereas quantum is futuristic, esoteric, ethereal. Jam quantum and mechanics together and you embody the ironies of quantum mechanics.

About Doubt

The day after I watched Sabine Hossenfelder’s video on superposition and entanglement, I reached out to her and other experts for guidance on what I should learn. I spent the summer of 2020 studying physics textbooks and doing exercises in calculus and linear algebra. In the fall of 2020, I took PEP553: Quantum Mechanics and Engineering Applications, a course offered at Stevens Institute. Two classmates, Dean and Luis, became my study buddies.

A sample of what my girlfriend calls my “scary Unabomber writing.” In this notebook entry, dated February 6, 2021, I wonder whether investigations of quantum mechanics will lead to an infinite regress of what physicist Terry Rudolph calls “mist” (explained in Chapter Eleven). EOS stands for “End of Science.”

In 2021, I crossed paths with Terry Rudolph, the grandson of Erwin Schrodinger, of the equation and cat. My encounter with Rudolph marked a turning point in my project. Rescuing me from a bout of gloom, when my experiment was on the verge of collapse, Rudolph taught me quantum mechanics by teaching me quantum computing, a field in which he is deeply involved. Meanwhile, I filled a half dozen 8-by-11-inch notebooks with what Emily describes as my “scary Unabomber handwriting.” This book is based on these notebooks, which record my thoughts, second thoughts and Nth thoughts on my studies.

When my experiment began, I had a few basic questions in mind: Could an oldster like me, starting more or less from scratch, learn the mathematical principles underpinning superposition and other quantum puzzles? If so, would that knowledge alter my views of quantum mechanics and related theories? Would it make me reconsider my bleak take on physics’ future? The answer to these questions turned out to be yes.

I’ve learned a lot about quantum mechanics. When I re-watch Hossenfelder’s video on superposition and entanglement now, I get it. That is, I recognize the terms she utters and even the equations she displays. She no longer loses me when she says that the wave function, symbolized by Ψ, “is a complex valued function and from its absolute square you calculate the probability of a measurement outcome.”

I can explain—and will explain, later in this book--how superposition and entanglement are linked. Readers will become familiar with other concepts: imaginary and complex numbers; matrices and vectors; Euler’s identity, the three-body problem and Bayesian probability. I’ll tell you about conservation of information, otherwise known as the minus first law; and the principle of least action, which I call the law of laziness. I’ll delve into qubits, the fuzzy chunks of information that make quantum computing possible.

When my experiment began, Sabine Hossenfelder predicted that someday an interpretation of quantum mechanics would be named after me. She was kidding, but I decided to take her seriously. Toward the end of this book, I present my very own interpretation of quantum mechanics.

But this book, I must warn you, isn’t about quantum mechanics, per se, so much as it is about my efforts to understand the theory. Most physics authors present their conclusions as glossy finished products, omitting their struggles and doubts. This book is about struggle and doubt. I tell the story of my quantum experiment as a memoir, in the present tense, with all the emotional ups and downs.

My buddy Robert Hutchinson. We never did make it to Namibia. Photo: Ruth Hutchinson.

I riff on connections between physics and happenings in my personal life and the wider world. In the first year of my project, my father died. Covid-19 swept across the planet, killing millions of people. A contentious Presidential election wracked my country. A white policeman killed a black man in Minneapolis, triggering protests nation-wide. The cancer of my friend Robert surged and ebbed. Winding sinusoidally through all of this was my relationship with Emily.

I began my experiment hoping to get away from politics, the pandemic, the cacophonous human shit show. Not to mention the hassle of love and friendship. I wanted to retreat into the austere realm of physics, where impersonal forces push particles back and forth. But my project kept dragging me back into the messy human world. Quantum mechanics forces us to ask, What is real? Life kept reminding me that suffering is real, our yearning for justice and freedom is real, love is real, even though these things are hard to find in physicists’ formulas.

I obsess, especially, over death. Several friends, when I disclosed this theme, asked, How is death related to quantum mechanics? They seemed genuinely puzzled. Their puzzlement puzzles me, because death, to my mind, is so self-evidently related to everything. Whether or not we consciously brood over it, death is always there; it is the backdrop for all our ventures, including our attempts to comprehend and control nature. And I’ve been brooding over death quite consciously lately. Death and Quantum Mechanics could serve as a title for this book.

I could cite quantum interpretations to justify my subjective narrative style. QBism (pronounced like the art movement) says quantum mechanics isn’t about reality; it is about our beliefs about reality. Agential realism insists that quantum mechanics must be understood within its cultural, political and ethical context. The relational interpretation says relations between things, and not things in themselves, underpin everything.

But well before I encountered these ideas (which I’ll tell you more about later), I had decided that when you try to interpret scientific theories, to say what they mean, you have left objectivity behind and entered the realm of analogy and metaphor, of art, where subjectivity reigns. In this realm, feelings matter. Our fears and desires can obscure the world, yes, they can mislead us, but they can also guide us toward truth. Feelings can even embody truth—or so I came to suspect during my quantum experiment.

Weirdness

While I have learned a lot during my experiment, I have also unlearned a lot. I’ve always been obsessed with the limits of knowledge, with what we can and can’t know. My struggle to understand quantum mechanics makes me wonder whether we understand anything. I’ve become acutely aware of how language, including mathematics, the language of numbers, conceals as it reveals. Another warning: This project has rekindled my youthful passion for poetry, which expresses the inexpressible.

Quantum mechanics is often described as “weird,” meaning strange, inexplicable, improbable. But Newton’s theory of gravity is pretty weird, too. Chunks of matter separated by vast spans of space tug on each other? Come on, tell me another one. And Einstein’s theory of gravity, which replaced Newton’s, renders space and time pliable. Totally weird. [2]

Sunrise as seen from my apartment in Hoboken. That is the Freedom Tower rising above the Hudson River and Manhattan skyline.

Far, far weirder are the things these theories describe. The universe, the Milky Way, the Sun, Earth and Moon. The Hudson River, which I can see outside my window when I’m home in Hoboken. The Freedom Tower, rising above the Manhattan skyline where the Twin Towers once stood. The ferries churning back and forth across the river. Weirdest of all are the creatures on those ferries--and that should not be surprising. We are, after all, made of quarks and electrons, weird quantum stuff.

Ikkyu, a 15th-century Zen sage, defined enlightenment as paying attention. The biggest barrier to paying attention is habituation. We get accustomed to the world. We plod through our lives like automatons, even when it comes to tasks that are meaningful to us. Finish grading this batch of freshman papers. Buy your girlfriend chocolate for Valentine’s Day. Email your friend to ask how his new chemo is going.

I’ve gone to great lengths to disrupt my habituation. I’ve chanted mantras on a Buddhist retreat, chewed peyote on a Navajo reservation, drunk ayahuasca on a cliff overlooking the Pacific. These interventions usually have fleeting effects. Studying quantum mechanics has disrupted my habituation in a way that feels permanent. The theory is riddled with contradictions; it mocks our confidence that we know anything about anything. If habituation is the problem, quantum mechanics is the solution, precisely because it defies solution.

My son Mac, who climbs rocks, says rock-climbers separate experiences into three categories:

1.     Fun when you’re doing it and fun to remember.

2.     Not much fun when you’re doing it but fun to remember.

3.     Not fun when you’re doing it and not fun to remember.

Type-3 experiences usually involve serious injury or death. Hard-core climbers, Mac informs me, think type-3 experiences are the most fun of all, if you define fun as profoundly meaningful. Compared to scaling El Capitan, which my son has done, or trekking through Namibia’s Fish River Canyon, my project has been humdrum. For the most part, I lie on my couch reading and writing. Weather permitting, I might take a collapsible chair into a park and study Quick Calculus as children cavort around me. Also, I have studied quantum mechanics in its most rudimentary form. Thousands of youngsters at my school and elsewhere learn the theory with little fuss year after year.

That red speck is my son Mac climbing El Capitan in 2018. Fail to learn quantum mechanics, you feel dumb. Fail to climb a mountain, you can end up dead. Photo: Tom Evans of El Cap Report.

My quantum experiment has nonetheless been one of my life’s great adventures. Now and then I felt too old, stupid and depressed to continue—for example, while trying to do homework for PEP553: Quantum Mechanics and Engineering Applications. Maybe those were type-2 experiences. But for the most part this project has been fun, and more. It has given me a sense of purpose when the world seemed to be falling apart.

More than a year after my experiment began, Bob Wright, a fellow seeker and writer, invited me onto his podcast, Meaningoflife.tv. Wright, author of the bestseller Why Buddhism Is True, has found his path. But he has always been curious about quantum mechanics, and he wanted to know if I’d reached any grand conclusions about it. I told Bob that the more I ponder quantum mechanics, the more befuddled I get, and not just about quantum mechanics. Wright, a canny fellow, said with a sly grin that “Old man gets more befuddled” doesn’t seem like a very happy ending for my project. Yeah, I replied, but that’s not a bad description of my experiment: Old man gets more befuddled. [3]

That’s not a bad description of my life, either, it occurs to me now. And if befuddlement isn’t a happy ending, that’s because it’s not an ending. Befuddlement keeps me going, it nudges me out of my torpor, it forces me to pay attention to this weird, weird world before it’s gone.

Notes

  1. A savvy agent, who tried to sell this book for me, advised me not to disclose that I began my quantum experiment with the goal of writing a book about it; readers would find that motive impure. But I am a writer, so my motives are always impure. Whatever I do, whatever happens to me, I’m thinking, Can I write about this? That’s why this chapter includes the exchange between me and Emily about whether my project might become a book.

  2. Spooky Action at a Distance, the 2015 book by physics writer George Musser, does a great job showing how Newtonian gravity and other pre-quantum theories anticipate the paradoxes of quantum mechanics, such as nonlocality.

  3. The savvy agent (see note 1) agreed with Bob Wright that “old man gets more befuddled” isn’t a great payoff for a book with commercial aspirations. Why would anyone want to read a book by an author who admits he is befuddled? Good question.

 

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