by Dan Ariely
Myhrvold has a favorite riddle: “If you have two steaks, one that’s an inch thick, one that’s two inches thick, how much longer does the thicker one need to cook?”
If you said the thicker steak takes twice as long, you’re making the same mistake most cooks do. “It’s four times as long. It goes roughly like the square,” Myhrvold says. “How come cookbooks don’t tell you that?” he asks, nearly bursting with indignation. The fundamental laws of heat, he figures, are the fundamental laws of cooking. “The physics of heat is diffusion,” Myhrvold says. “So that’s also the physics of drying things or of marination. They’re all about diffusing things. The physics of heating things is also the physics of cooling things. It’s the same basics over and over.”
Then there’s water. “Three things about water affect almost all of cooking,” Myhrvold says. “First are the hydrogen bonds, which is why it has an incredibly high boiling point. Another is that it’s a polar molecule, so that it dissolves a lot of things, and there are things that won’t mix with it. And then there’s how much energy it takes to heat water. That’s why steaming food works; that’s why pressure cookers work.”
This isn’t like most writing about food science. McGee’s science-minded On Food and Cooking is a de facto reference in every professional kitchen—and many amateur ones. McGee says he’s a fan of Myhrvold’s work; the two men are friends, in fact. “I’m much more interested in the chemistry of flavor than Nathan is,” McGee says. “That has to do with the diversity of compounds that you find in nature, how they get there, and how we detect them.”
It’s a polite sort of turf-carving, and Myhrvold is in just as much of a rush to establish his own. “In terms of broadly looking at food science and chemistry, and trying to explain it to a lay audience, Harold led the way,” Myhrvold says. “But we have a physics-oriented book.” Most cooks focus on the difference between filet mignon and rib eye. Myhrvold and his team want you to comprehend the whole cow. “If all you want to do is follow recipes, you don’t need insights,” he says. “If you want to do new things, you have to understand what the hell you’re doing.”
The ambition, the sheer bigness of Modernist Cuisine, does trigger the oh-come-on meter just a bit. Saying cooks need to understand the physics of diffusion is a little bit like saying a home woodworker needs to understand quantum mechanics. Sure, Planck’s constant helps explain how nails go through maple, but calculating the one doesn’t help you hammer the other.
Ironically, Modernist Cuisine will start tormenting UPS drivers with its bulk at the same time that the movement it celebrates—avant-garde, science-driven cooking—is waning. Ferran Adrià is closing El Bulli this year. Achatz is opening a new restaurant this spring that won’t emphasize the techniques he helped popularize. “I think the book will have long-lasting importance in gastronomy,” Achatz says. “But the particular style of cooking that it highlights might not. It’s clear that the tide is turning. I don’t think many chefs will continue to take the wholehearted scientific approach.”
The tools and techniques that chefs like Adrià and Achatz popularized are trickling down. Flip on Top Chef and you’re likely to see someone mucking about with liquid nitrogen and vacuum sealers. But the artistic part, the creativity of avant-garde chefs that Myhrvold finds so inspiring, seems to be shrinking. If that’s so, Modernist Cuisine isn’t the Principia of the kitchen but its Consolation of Philosophy, the book that collects and summarizes all the knowledge in a field at the moment the field implodes. It’s a eulogy.
Myhrvold has certainly considered that possibility. To get this book out, he spent hundreds of thousands, maybe even millions, hiring staff, building a lab, setting up a separate company to self-publish it. And while he might be relatively immune to financial pressures, there’s another judgment that the market will make. “One of the names for small-volume personal publishing is vanity publishing,” Myhrvold says. “So is this useful to people, or is it entirely vanity? That’s a fascinating question. If no one wants it, you have to ask yourself, what am I doing it for?”
It’s almost impossible to comprehend all of Modernist Cuisine. It seeks to be the first and last word in its field, to settle every argument, to capture all of human knowledge about cooking. And, ultimately, it’s a book that utterly reflects Myhrvold. “We had a focus on physics. We had a focus on computer modeling. We had a focus on photography,” Myhrvold says. “Those are all things that I’m completely into. We had a focus on the history and the philosophy of this kind of cuisine. Again, that’s totally what I’m into.” That’s why the criticisms won’t matter too much to Myhrvold. In the end, Modernist Cuisine is more than a cookbook. It’s an autobiography—the world’s most oblique memoir, so accurate a reflection of its creator that he might be the only person in the world who fully understands it.
RIVKA GALCHEN
Dream Machine
FROM The New Yorker
ON THE OUTSKIRTS of Oxford lives a brilliant and distressingly thin physicist named David Deutsch, who believes in multiple universes and has conceived of an as yet unbuildable computer to test their existence. His books have titles of colossal confidence (The Fabric of Reality, The Beginning of Infinity). He rarely leaves his house. Many of his close colleagues haven’t seen him for years, except at occasional conferences via Skype.
Deutsch, who has never held a job, is essentially the founding father of quantum computing, a field that devises distinctly powerful computers based on the branch of physics known as quantum mechanics. With one-millionth of the hardware of an ordinary laptop, a quantum computer could store as many bits of information as there are particles in the universe. It could break previously unbreakable codes. It could answer questions about quantum mechanics that are currently far too complicated for a regular computer to handle. None of which is to say that anyone yet knows what we would really do with one. Ask a physicist what, practically, a quantum computer would be “good for,” and he might tell the story of the nineteenth-century English scientist Michael Faraday, a seminal figure in the field of electromagnetism, who, when asked how an electromagnetic effect could be useful, answered that he didn’t know, but he was sure that one day it could be taxed by the queen.
In a stairwell of Oxford’s Clarendon Physics Laboratory there is a photo poster from the late 1990s commemorating the Oxford Center for Quantum Computation. The photograph shows a well-groomed crowd of physicists gathered on the lawn. Photoshopped into a far corner, with the shadows all wrong, is the head of David Deutsch, looking like a time traveler teleported in for the day. It is tempting to interpret Deutsch’s representation in the photograph as a collegial joke, because of Deutsch’s belief that if a quantum computer were built it would constitute near-irrefutable evidence of what is known as the Many Worlds Interpretation of quantum mechanics, a theory that proposes pretty much what one would imagine it does. A number of respected thinkers in physics besides Deutsch support the Many Worlds Interpretation, though they are a minority, and primarily educated in England, where the intense interest in quantum computing has at times been termed the Oxford flu.
But the infection of Deutsch’s thinking has mutated and gone pandemic. Other scientists, although generally indifferent to the truth or falsehood of Many Worlds as a description of the universe, are now working to build these dreamed-up quantum-computing machines. Researchers at centers in Singapore, Canada, and New Haven, in collaboration with groups such as Google and NASA, may soon build machines that will make today’s computers look like pocket calculators. But Deutsch complements the indifference of his colleagues to Many Worlds with one of his own—a professional indifference to the actual building of a quantum computer.
Physics advances by accepting absurdities. Its history is one of unbelievable ideas proving to be true. Aristotle quite reasonably thought that an object in motion, left alone, would eventually come to rest; Newton discovered that this wasn’t true, and from there worked out the foundation of what we now call classical mechanics. S
imilarly, physics surprised us with the facts that Earth revolves around the sun, time is curved, and the universe if viewed from the outside is beige.
“Our imagination is stretched to the utmost,” the Nobel Prize–winning physicist Richard Feynman noted, “not, as in fiction, to imagine things which are not really there, but just to comprehend those things which are there.” Physics is strange, and the people who spend their life devoted to its study are more accustomed to its strangeness than the rest of us. But even to physicists, quantum mechanics—the basis of a quantum computer—is almost intolerably odd.
Quantum mechanics describes the natural history of matter and energy making their way through space and time. Classical mechanics does much the same, but while classical mechanics is very accurate when describing most of what we see (sand, baseballs, planets), its descriptions of matter at a smaller scale are simply wrong. At a fine enough resolution, all those reliable rules about balls on inclined planes start to fail.
Quantum mechanics states that particles can be in two places at once, a quality called superposition; that two particles can be related, or “entangled,” such that they can instantly coordinate their properties, regardless of their distance apart in space and time; and that when we look at particles we unavoidably alter them. Also, in quantum mechanics the universe, at its most elemental level, is random, an idea that tends to upset people. Confess your confusion about quantum mechanics to a physicist and you will be told not to feel bad, because physicists find it confusing, too. If classical mechanics is George Eliot, quantum mechanics is Kafka.
All the oddness would be easier to tolerate if quantum mechanics merely described marginal bits of matter or energy. But it is the physics of everything. Even Einstein, who felt at ease with the idea of wormholes through time, was so bothered by the whole business that in 1935 he coauthored a paper titled “Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?” He pointed out some of quantum mechanics’ strange implications, and then answered his question, essentially, in the negative. Einstein found entanglement particularly troubling, denigrating it as “spooky action at a distance,” a telling phrase, which consciously echoed the seventeenth-century disparagement of gravity.
The Danish physicist Niels Bohr took issue with Einstein. He argued that in quantum mechanics, physics had run up against the limit of what science could hope to know. What seemed like nonsense was nonsense, and we needed to realize that science, though wonderfully good at predicting the outcomes of individual experiments, could not tell us about reality itself, which would remain forever behind a veil. Science merely revealed what reality looked like to us.
Bohr’s stance prevailed over Einstein’s. “Of course, both sides of that dispute were wrong,” Deutsch observed, “but Bohr was trying to obfuscate, whereas Einstein was actually trying to solve the problem.” As Deutsch notes in The Fabric of Reality, “To say that prediction is the purpose of a scientific theory is to confuse means with ends. It is like saying that the purpose of a spaceship is to burn fuel.” After Bohr, a “shut up and calculate” philosophy took over physics for decades. To delve into quantum mechanics as if its equations told the story of reality itself was considered sadly misguided, like those earnest inquiries people mail to 221B Baker Street, addressed to Sherlock Holmes.
I met David Deutsch at his home, at four o’clock on a wintry Thursday afternoon. Deutsch grew up in the London area, took his undergraduate degree at Cambridge, stayed there for a master’s in math—which he claims he’s no good at—and went on to Oxford for a doctorate in physics. Though affiliated with the university, he is not on staff and has never taught a course. “I love to give talks,” he told me. “I just don’t like giving talks that people don’t want to hear. It’s wrong to set up the educational system that way. But that’s not why I don’t teach. I don’t teach for visceral reasons—I just dislike it. If I were a biologist, I would be a theoretical biologist, because I don’t like the idea of cutting up frogs. Not for moral reasons but because it’s disgusting. Similarly, talking to a group of people who don’t want to be there is disgusting.” Instead, Deutsch has made money from lectures, grants, prizes, and his books.
In the half-light of the winter sun, Deutsch’s house looked a little shabby. The yard was full of what appeared to be English ivy, and near the entrance was something twiggy and bushlike that was either dormant or dead. A handwritten sign on the door said that deliveries should “knock hard.” Deutsch answered the door. “I’m very much in a rush,” he told me, before I’d even stepped inside. “In a rush about so many things.” His thinness contributed to an oscillation of his apparent age between nineteen and a hundred and nineteen. (He’s fifty-seven.) His eyes, behind thick glasses, appeared outsized, like those of an appealing anime character. His vestibule was cluttered with old phone books, cardboard boxes, and piles of papers. “Which isn’t to say that I don’t have time to talk to you,” he continued. “It’s just that—that’s why the house is in such disarray, because I’m so rushed.”
More than one of Deutsch’s colleagues told me about a Japanese documentary film crew that had wanted to interview Deutsch at his house. The crew asked if they could clean up the house a bit. Deutsch didn’t like the idea, so the film crew promised that after filming they would reconstruct the mess as it was before. They took extensive photographs, like investigators at a crime scene, and then cleaned up. After the interview, the crew carefully reconstructed the former “disorder.” Deutsch said he could still find things, which was what he had been worried about.
Taped onto the walls of Deutsch’s living room were a map of the world, a periodic table, a hand-drawn cartoon of Karl Popper, a poster of the signing of the Declaration of Independence, a taxonomy of animals, a taxonomy of the characters in The Simpsons, color printouts of pictures of McCain and Obama, with handwritten labels reading “this one” and “that one,” and two color prints of an actor who looked to me a bit like Hugh Grant. There were also old VHS tapes, an unused fireplace, a stationary exercise bike, and a large flat-screen television whose newness had no visible companion. Deutsch offered me tea and biscuits. I asked him about the Hugh Grant look-alike.
“You obviously don’t watch much television,” he replied. The man in the photographs was Hugh Laurie, a British actor known for his role in the American medical show House. Deutsch described House to me as “a great program about epistemology, which, apart from fundamental physics, is really my core interest. It’s a program about the myriad ways that knowledge can grow or can fail to grow.” Dr. House is based on Sherlock Holmes, Deutsch informed me. “And House has a friend, Wilson, who is based on Watson. Like Holmes, House is an arch-rationalist. Everything’s got to have a reason, and if he doesn’t know the reason it’s because he doesn’t know it, not because there isn’t one. That’s an essential attitude in fundamental science.” One imagines the ghost of Bohr would disagree.
Deutsch’s reputation as a cloistered genius stems in large part from his foundational work in quantum computing. Since the 1930s, the field of computer science has held on to the idea of a universal computer, a notion first worked out by the field’s modern founder, the British polymath Alan Turing. A universal computer would be capable of comporting itself like any other computer, just as a synthesizer can make the sounds made by any other musical instrument. In a 1985 paper, Deutsch pointed out that because Turing was working with classical physics, his universal computer could imitate only a subset of possible computers. Turing’s theory needed to account for quantum mechanics if its logic was to hold. Deutsch proposed a universal computer based on quantum physics, which would have calculating powers that Turing’s computer (even in theory) could not simulate.
According to Deutsch, the insight for that paper came from a conversation in the early eighties with the physicist Charles Bennett of IBM about computational-complexity theory, at the time a sexy new field that investigated the difficulty of a computational task. Deutsch questioned whet
her computational complexity was a fundamental or a relative property. Mass, for instance, is a fundamental property, because it remains the same in any setting; weight is a relative property, because an object’s weight depends on the strength of gravity acting on it. Identical baseballs on Earth and on the moon have equivalent masses but different weights. If computational complexity was like mass—if it was a fundamental property—then complexity was quite profound; if not, then not.
“I was just sounding off,” Deutsch said. “I said they make too much of this”—meaning complexity theory—“because there’s no standard computer with respect to which you should be calculating the complexity of the task.” Just as an object’s weight depends on the force of gravity in which it’s measured, the degree of computational complexity depended on the computer on which it was measured. One could find out how complex a task was to perform on a particular computer, but that didn’t say how complex a task was fundamentally, in reference to the universe. Unless there really was such a thing as a universal computer, there was no way a description of complexity could be fundamental. Complexity theorists, Deutsch reasoned, were wasting their time.
Deutsch continued, “Then Charlie said, quietly, ‘Well, the thing is, there is a fundamental computer. The fundamental computer is physics itself.’” That impressed Deutsch. Computational complexity was a fundamental property; its value referenced how complicated a computation was on that most universal computer, that of the physics of the world. “I realized that Charlie was right about that,” Deutsch said. “Then I thought, But these guys are using the wrong physics. They realized that complexity theory was a statement about physics, but they didn’t realize that it mattered whether you used the true laws of physics, or some approximation, i.e., classical physics.” Deutsch began rewriting Turing’s universal-computer work using quantum physics. “Some of the differences are very large,” he said. Thus, at least in Deutsch’s mind, the quantum universal computer was born.