Richard Feynman

Based on Wikipedia: Richard Feynman

The Physicist Who Thought Like a Bum

When Richard Feynman gave his very first scientific seminar at Princeton University, the audience included three of the most brilliant minds of the twentieth century: Albert Einstein, Wolfgang Pauli, and John von Neumann. Feynman was twenty-three years old. He had not yet earned his doctorate. And he was about to present a theory so ambitious that Pauli would warn it might be impossible to develop mathematically, while Einstein would suggest it could revolutionize our understanding of gravity itself.

This was Feynman's style: show up, dazzle everyone, speak with a thick New York accent that made him sound like a street corner wise guy rather than a genius. His friends Wolfgang Pauli and Hans Bethe once remarked that Feynman spoke "like a bum." He took this as a compliment.

Feynman would go on to win the Nobel Prize in Physics, help build the atomic bomb, crack safes for fun at Los Alamos, play bongo drums at strip clubs, pioneer quantum computing before computers could compute much of anything, and become perhaps the most beloved explainer of science the world has ever known. A 1999 poll of physicists ranked him the seventh greatest physicist of all time, just behind names like Einstein and Newton.

But what made Feynman extraordinary wasn't just his intellect. It was his absolute refusal to accept any idea he couldn't understand from the ground up, his delight in puzzles of every kind, and his conviction that the universe was too interesting to approach with false reverence.

A Mind Built in Far Rockaway

Richard Phillips Feynman was born on May 11, 1918, in New York City. His father, Melville, had immigrated from Minsk in the Russian Empire as a five-year-old boy. His mother, Lucille, came from a family of Polish Jewish immigrants. Melville worked as a sales manager; Lucille had trained as a teacher but never practiced after marrying in 1917.

Richard was a late talker. He didn't speak until after his third birthday—a detail that might alarm modern parents but apparently caused little concern in the Feynman household. When he did finally start talking, he made up for lost time with an accent so pronounced, so unmistakably working-class New York, that people who met him as an adult sometimes thought he was putting it on.

His father shaped his mind. Melville Feynman had a simple educational philosophy: question everything, especially the things everyone else accepts without thinking. When young Richard asked why a ball in a wagon rolled backward when the wagon started moving forward, his father didn't just explain inertia—he explained that giving something a name doesn't mean you understand it. This became Feynman's lifelong obsession: the difference between knowing the name of something and actually knowing the thing itself.

His mother gave him something equally important: a sense of humor. Lucille Feynman had a gift for finding absurdity in everyday life, and Richard inherited it completely. Throughout his career, he would approach the deepest mysteries of physics with the same playful irreverence that his mother brought to household mishaps.

As a child, Richard was an inveterate tinkerer. He built a home laboratory, repaired radios for neighbors (probably his first paying job), and rigged a burglar alarm for his parents' house. What distinguished his radio repair work was his method: rather than just poking around until something worked, he would think through the problem theoretically, reason out what must be wrong, and then verify his hypothesis. He was doing physics before he knew what physics was.

The Sister Who Would Explain the Northern Lights

When Richard was five, his mother gave birth to a second son, Henry Phillips. The baby died at four weeks old. Four years later, Joan was born, and the family moved to Far Rockaway, a neighborhood in Queens that sits at the end of the A train line, where the city meets the Atlantic Ocean.

Joan and Richard were separated by nine years, but they were close in the way that matters: they shared an insatiable curiosity about how the world worked. Their mother, like many people of her generation, believed that women lacked the capacity for scientific thinking. Richard disagreed. He encouraged Joan's interest in astronomy, once waking her in the middle of the night to take her outside and watch the aurora borealis dance across the sky above Far Rockaway.

Joan became an astrophysicist. Among the phenomena she would help explain? The northern lights her brother had shown her as a child.

An IQ of 125 and a Perfect Score

Feynman attended Far Rockaway High School, which had a remarkable run of producing Nobel laureates—Burton Richter and Baruch Samuel Blumberg also walked its halls. Almost immediately, he was bumped up to a more advanced math class. The teachers couldn't keep up with him.

Here's a detail that Feynman loved to mention: when his high school administered an IQ test, he scored 125. This is a good score. It is not a genius score. His sister Joan scored 126. For the rest of their lives, Joan would tease him about being the smarter sibling.

Feynman later declined to join Mensa, the high-IQ society, claiming his IQ was too low for membership. This was a joke, but it also reflected his genuine contempt for the idea that intelligence could be reduced to a single number. The same mind that scored 125 on a standardized test would later achieve a perfect score on Princeton's graduate physics entrance exam—something no one had ever done before.

By fifteen, Feynman had taught himself trigonometry, advanced algebra, infinite series, analytic geometry, and both differential and integral calculus. He wasn't just learning mathematics; he was reinventing it. He created his own notation, designing special symbols for common functions because he thought the standard notation was confusing. Why, he wondered, should the sine function look like it's three variables multiplied together? Why should the derivative symbol tempt students into thinking they can cancel out the d's?

In his final year of high school, he won the New York University Math Championship. His direct, question-everything approach sometimes startled people. When taking a biology class that covered cat anatomy, he asked the instructor: "Do you have a map of the cat?"

Columbia's Loss, MIT's Gain

Feynman applied to Columbia University and was rejected. The reason had nothing to do with his abilities: Columbia maintained a quota limiting how many Jewish students it would admit. This was common practice at elite American universities in the 1930s, a casual antisemitism woven into the fabric of academic life.

Instead, Feynman went to the Massachusetts Institute of Technology, where he joined the Pi Lambda Phi fraternity and began the intellectual journey that would define his life. He started as a mathematics major but found it too abstract—math for math's sake left him cold. He switched to electrical engineering, then decided that was too practical. Physics, he concluded, was "somewhere in between." It was the sweet spot where abstract mathematical beauty met the concrete reality of how the universe actually works.

As an undergraduate, he published two papers in the Physical Review, one of the most prestigious physics journals in the world. One paper, on cosmic rays, was co-authored with his professor Manuel Vallarta. Following academic convention, Vallarta's name came first. Feynman got his revenge years later when the legendary physicist Werner Heisenberg concluded an entire book on cosmic rays with the phrase "such an effect is not to be expected according to Vallarta and Feynman."

When they next met, Feynman gleefully asked Vallarta if he'd seen Heisenberg's book.

Vallarta knew exactly why his former student was grinning. "Yes," he replied. "You're the last word in cosmic rays."

Princeton and the Question of Jewishness

In 1939, Feynman graduated from MIT as a Putnam Fellow—one of the highest honors in undergraduate mathematics—and applied to Princeton for graduate school. His performance on the entrance exams was extraordinary: perfect in physics, outstanding in mathematics. He bombed history and English.

But there was another concern. Henry D. Smyth, the head of Princeton's physics department, wrote a letter asking about Feynman: "Is Feynman Jewish? We have no definite rule against Jews but have to keep their proportion in our department reasonably small because of the difficulty of placing them."

Philip Morse, who had recommended Feynman, admitted that yes, Feynman was Jewish, but reassured Smyth that "his physiognomy and manner, however, show no trace of this characteristic." In other words: don't worry, he doesn't look or act Jewish.

It's worth pausing here. This is how one of the greatest scientific minds of the twentieth century nearly got excluded from one of the world's finest physics programs: through the genteel antisemitism of academics who liked to believe they weren't prejudiced while maintaining unwritten quotas and evaluating Jewish applicants by how well they could pass for gentile.

Feynman himself had a complicated relationship with his Jewish heritage. His family attended synagogue every Friday when he was young, but by his teenage years, he described himself as an "avowed atheist." Years later, when an author writing a book about Jewish Nobel Prize winners asked for his participation, Feynman declined with characteristic bluntness: "To select, for approbation the peculiar elements that come from some supposedly Jewish heredity is to open the door to all kinds of nonsense on racial theory."

He added that at thirteen, he had stopped believing "that the Jewish people are in any way 'the chosen people.'"

The Path Integral and Electrons Moving Backward Through Time

At Princeton, Feynman's thesis advisor was John Archibald Wheeler, a brilliant and creative physicist who would later coin the term "black hole." Together, they developed something called the Wheeler-Feynman absorber theory, an attempt to reimagine the fundamental equations of electromagnetism—the theory that describes how light, electricity, and magnetism all interrelate.

That first seminar, the one attended by Einstein, Pauli, and von Neumann, presented this work. The reactions were telling. Pauli, known for his devastating critiques, warned that the theory would be "extremely difficult to quantize"—meaning it would be hard to make compatible with quantum mechanics, the weird rules that govern atoms and subatomic particles. Einstein, ever thinking about gravity, suggested the approach might be useful for his general theory of relativity. Both predictions proved correct.

For his doctoral thesis, Feynman developed what would become his signature contribution to physics: the path integral formulation of quantum mechanics. To understand why this matters, you need to understand the problem it solved.

In classical physics—the physics of Newton and everyday experience—a ball thrown through the air follows a single path. You can calculate that path, predict where the ball will land. But quantum mechanics revealed that subatomic particles don't work this way. An electron doesn't follow a single path. It somehow explores all possible paths simultaneously, and what we observe is a kind of average over all these possibilities.

Feynman's insight was to take this literally. Instead of trying to figure out which path a particle "really" takes, calculate the contributions from every possible path the particle could take, weight them appropriately, and sum them all up. This "path integral" approach turned out to be mathematically equivalent to the standard quantum mechanical equations, but it offered a completely different way of thinking about what was happening.

Along the way, Feynman realized something remarkable: the mathematics worked out much more elegantly if you treated positrons—the antimatter version of electrons—as electrons traveling backward in time. This wasn't just a mathematical trick. It was a deep insight into the symmetry of physical laws, and it would prove essential for the work that later won him the Nobel Prize.

James Gleick, Feynman's biographer, described this period: "This was Richard Feynman nearing the crest of his powers. At twenty-three... there may now have been no physicist on earth who could match his exuberant command over the native materials of theoretical science."

Arline

Throughout his Princeton years, Feynman was in love with his high school sweetheart, Arline Greenbaum. There was a problem: one of the conditions of his graduate scholarship was that he could not be married.

There was a much bigger problem: Arline had tuberculosis. This was 1942. There were no antibiotics that could treat tuberculosis. The doctors gave her two years to live, at most.

Feynman married her anyway.

On June 29, 1942, they took the ferry to Staten Island and were married in the city clerk's office. No family attended. No friends. Two strangers served as witnesses. Because of her illness, Feynman could kiss Arline only on the cheek. After the ceremony, he took her to Deborah Hospital, where she would spend the rest of her short life.

He visited her on weekends. He was twenty-four years old, newly married, preparing to help build the most destructive weapon in human history, and spending his Saturdays watching the woman he loved slowly die of a disease that no one could cure.

Los Alamos

The summer before his marriage, with World War II raging in Europe but America not yet involved, Feynman had worked on ballistics problems at the Frankford Arsenal in Pennsylvania. After Pearl Harbor, Robert R. Wilson recruited him for a secret project to produce enriched uranium—the fuel for an atomic bomb.

Feynman had not yet finished his doctorate. He was assigned to work on a device called an isotron, which was supposed to separate the fissile uranium-235 from the more common uranium-238 using electromagnetic fields. On paper, the isotron was far more efficient than the alternative approach being developed at Berkeley. In practice, Feynman and his colleague Paul Olum couldn't figure out whether it would actually work. The project was eventually abandoned.

In early 1943, Robert Oppenheimer began assembling scientists at a secret laboratory on a mesa in New Mexico called Los Alamos. Wilson's entire Princeton team signed up to go. "Like a bunch of professional soldiers," Wilson recalled, "we signed up, en masse."

Oppenheimer made arrangements for Arline. He found a Presbyterian sanatorium in Albuquerque, about a hundred miles from Los Alamos, where she could receive care. Richard and Arline were among the first to leave for New Mexico, departing by train on March 28, 1943. The railroad provided Arline with a wheelchair; Richard paid extra for a private room. They spent their wedding anniversary on that train, traveling toward a desert mesa where physicists would attempt to harness the energy that powers the sun.

At Los Alamos, Feynman was assigned to the Theoretical Division under Hans Bethe. Bethe was so impressed that he made Feynman a group leader, despite his youth and junior status. Together, they developed the Bethe-Feynman formula for calculating the explosive yield of a fission bomb.

Feynman's official job was not central to the bomb design itself. He administered a computation group—not computers in the modern sense, but human beings (mostly women) who performed calculations by hand or with mechanical calculators. With Stanley Frankel and Nicholas Metropolis, he helped set up a system using IBM punched cards to speed up the calculations. This was computing before computers: feeding stacks of cards into machines, waiting for results, debugging the process when cards got bent or fed in wrong.

He also invented a new method for computing logarithms, which proved so efficient that decades later, he would use it again on the Connection Machine, one of the first massively parallel supercomputers.

And because he was Feynman, he figured out how to get the IBM card machines to click in musical rhythms. Even while helping build a weapon that would kill over a hundred thousand people in an instant, he couldn't resist turning computation into percussion.

The Safe-Cracker of Los Alamos

Los Alamos was a pressure cooker—hundreds of the world's most brilliant scientists crammed onto an isolated mesa, doing secret work that would determine the outcome of the war. People found different ways to cope. Feynman's way was to crack safes.

The laboratory was filled with filing cabinets containing classified documents, each protected by combination locks. Feynman made it his hobby to open them. Sometimes he did it through patient analysis—figuring out that most people chose combinations based on memorable numbers, or that the tolerances in the locks meant you only had to get within a couple of digits of the right combination. Sometimes he just watched people open their safes and memorized the combinations. Sometimes he found the factory default combinations still worked because nobody had bothered to change them.

The security officers were not amused. Here was a project so secret that scientists couldn't tell their own families what they were working on, and this kid from New York was wandering around opening locked cabinets for fun.

Feynman, characteristically, saw it as a public service. He was demonstrating that the security measures didn't actually work. If he could open those safes, so could a spy. The fact that this annoyed the security people just made it more entertaining.

The Final Problem

On July 16, 1945, the first atomic bomb was tested at Trinity Site in the New Mexico desert. Feynman was one of the few people to watch the explosion without protective goggles—he reasoned, correctly, that the windshield of a truck would filter out the harmful ultraviolet radiation while still letting him see the blast directly.

What he saw was a brilliant flash, brighter than anything he had ever experienced, followed by a growing fireball and then, long seconds later, the sound—a thunder that rolled across the desert and seemed to echo off the mountains.

The bomb worked. Within a month, two more would be dropped on Japan. Hundreds of thousands of people would die, many instantly, many slowly from radiation sickness and burns and cancers that would emerge years later.

Feynman never expressed the moral anguish about the bomb that tormented some of his colleagues. He had started the work because the Nazis were trying to build an atomic bomb, and the prospect of Hitler with nuclear weapons was genuinely terrifying. By the time Germany surrendered in May 1945, the project had its own momentum. Feynman kept working. He later said he simply didn't think about the implications—he was too focused on the physics problems.

But something did break in him that summer.

Arline died on June 16, 1945, exactly one month before the Trinity test. She was twenty-five years old. She and Richard had been married for three years, almost all of it spent with her in hospitals and sanatoriums while he worked on the bomb. He had visited every weekend he could manage, bringing her presents, reading to her, trying to make her laugh. When she died, he was holding her hand.

In the weeks after, Feynman did something strange: he kept going, kept working, felt almost nothing. It was months before the grief hit him. He was walking through New York, he later recounted, and he saw a pretty dress in a shop window and thought, "Arline would like that." And then he remembered. And then, finally, he broke down.

Years later, a letter was found among his papers. It was addressed to Arline, written more than a year after her death. "I adore you, sweetheart," it read. "I know how much you like to hear that—but I don't only write it because you like it—I write it because it makes me warm all over inside to write it to you." He wrote about his life, about missing her, about small things and large things. At the end, he added a postscript: "P.S. Please excuse my not mailing this—but I don't know your new address."

He kept the letter for the rest of his life.

Quantum Electrodynamics and the Diagrams That Changed Physics

After the war, Feynman suffered what he later described as a period of creative paralysis. He had done world-changing work in his early twenties; now, in his late twenties, he couldn't seem to make progress on anything. He accepted a position at Cornell University, taught classes, and worried that his best work was behind him.

It wasn't.

The problem that would revive his career was quantum electrodynamics, or QED—the theory describing how light and matter interact at the quantum level. Physicists had been working on QED for years, but the theory had a fatal flaw: the equations kept producing infinite answers. Ask how an electron would scatter off another electron, and the calculations gave you infinity. Obviously wrong. Something was broken.

Feynman, along with Julian Schwinger in the United States and Sin-Itiro Tomonaga in Japan, independently found ways to fix the problem. The technique was called renormalization: a systematic way to cancel out the infinities and extract finite, testable predictions.

But Feynman's approach was different from the others in a crucial way. Schwinger and Tomonaga used traditional mathematical methods—long, complicated equations that only experts could follow. Feynman invented a visual language.

Feynman diagrams look deceptively simple. Lines represent particles. Wavy lines represent photons (particles of light). Time flows from left to right. Where lines meet, particles interact. By drawing all possible diagrams for a process and computing a contribution from each one, you could calculate anything in quantum electrodynamics.

Older physicists were initially skeptical. This was physics? It looked like doodling. But the diagrams worked. They gave the same answers as the ponderous traditional methods, in a fraction of the time. More importantly, they provided intuition. You could look at a Feynman diagram and see what was happening—electrons bouncing photons back and forth, particles emerging from the vacuum and disappearing again, the whole quantum dance of matter and light made visible.

Today, Feynman diagrams are everywhere in physics. Every particle physicist learns to draw them. They've been extended far beyond their original application, used to calculate processes involving not just electrons and photons but quarks, gluons, neutrinos, and exotic particles that exist for only billionths of a billionth of a second.

In 1965, Feynman, Schwinger, and Tomonaga shared the Nobel Prize in Physics for their work on quantum electrodynamics. The predictions of QED have since been tested to extraordinary precision—some calculations match experiments to twelve decimal places, making QED the most accurately verified theory in the history of science.

The Challenger Investigation

By the 1980s, Feynman was sixty-something, a legendary figure in physics, a bestselling author thanks to the anecdote collections "Surely You're Joking, Mr. Feynman!" and "What Do You Care What Other People Think?" He had survived cancer, remarried happily (to Gweneth Howarth, with whom he had two children), and settled into his role as the elder statesman of American physics.

Then, on January 28, 1986, the Space Shuttle Challenger exploded seventy-three seconds after launch, killing all seven astronauts aboard.

President Reagan appointed a commission to investigate. William Rogers, a former Secretary of State, chaired it. Feynman was among the members—somewhat reluctantly, since he didn't enjoy Washington politics and was dealing with a recurrence of his cancer.

What Feynman found appalled him. The immediate cause of the disaster was the failure of rubber O-ring seals in one of the solid rocket boosters. Cold weather on the morning of the launch had stiffened the rubber, preventing it from sealing properly. Hot gases leaked through, eventually igniting the external fuel tank.

But the deeper problem was institutional. NASA engineers had known for years that the O-rings were problematic. They had raised concerns. Management had dismissed them. The night before the launch, engineers from Morton Thiokol, the company that made the boosters, had argued strenuously against launching in cold weather. They were overruled.

Feynman conducted his own investigation, talking to engineers rather than managers, asking simple questions, refusing to accept bureaucratic non-answers. He discovered a stunning disconnect: when he asked NASA management to estimate the probability of shuttle failure, they gave numbers like 1 in 100,000. When he asked engineers, they said more like 1 in 100. A thousand-fold difference between what the people building the rockets believed and what the people running the program claimed.

The most famous moment came during a televised hearing. Feynman had obtained a sample of the O-ring rubber. While commission members droned on, he quietly dropped the rubber into a glass of ice water. Then, when it was his turn to speak, he pulled it out and demonstrated that the cold rubber had lost its flexibility—it didn't spring back to shape the way it should.

The demonstration was devastating. In thirty seconds, Feynman had shown the American public what all the reports and testimony had failed to convey: the basic physics of why Challenger exploded.

His appendix to the commission's report contained a famous conclusion: "For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled."

The Feynman Lectures

Between 1961 and 1964, Feynman taught an introductory physics course at the California Institute of Technology. This was unusual—famous professors typically avoided teaching freshmen. But Feynman threw himself into it, reimagining the entire undergraduate physics curriculum from scratch.

The lectures were recorded and transcribed, eventually published as "The Feynman Lectures on Physics." They became one of the most influential physics textbooks ever written—not because they made physics easy (they didn't) but because they made physics beautiful. Feynman had a gift for finding the deep principle behind surface complexity, for showing how the same few ideas echoed through apparently unrelated phenomena.

He was also honest about what physics couldn't explain. In one famous passage, he addressed a perennial student question: why do objects obey the principle of least action, taking paths that minimize a certain mathematical quantity? "I don't know," Feynman said. Nobody knows. It's just how nature works. The principle was a description, not an explanation.

This willingness to say "I don't know" was central to Feynman's character. He was allergic to false certainty, to people who pretended to understand things they didn't. He thought science was fundamentally about acknowledging ignorance and working systematically to reduce it—not about claiming to have all the answers.

There's Plenty of Room at the Bottom

In 1959, Feynman gave an after-dinner talk at a physics conference. It was called "There's Plenty of Room at the Bottom," and it outlined a vision that would take decades to realize: nanotechnology.

What if, Feynman asked, we could manipulate individual atoms? Build machines at the molecular scale? Write the entire Encyclopedia Britannica on the head of a pin? None of this violated any physical law. It was just very, very hard.

He offered prizes—$1,000 for the first person to build a working electric motor no bigger than 1/64th of an inch on a side, and another $1,000 for the first person to shrink a page of text by a factor of 25,000 (small enough to fit a book page on something the size of a period). Both prizes were eventually claimed.

The talk is now considered the founding document of nanotechnology. Feynman didn't do the work himself—he was a theorist, not an experimentalist—but he saw the possibility before almost anyone else. Today, we have scanning tunneling microscopes that can image and move individual atoms. We have molecular machines, carbon nanotubes, mRNA vaccines that work by delivering instructions to cellular machinery. Feynman's vision wasn't science fiction. It was science, waiting for the engineering to catch up.

The Character of Physical Law

Feynman was not just a great physicist. He was a great explainer of physics, with an ability to make complex ideas accessible without dumbing them down. His popular lectures and books introduced millions of people to the strange beauty of the quantum world.

But he was also something rarer: a physicist who thought deeply about what science was and how it worked. In "The Character of Physical Law," based on lectures delivered at Cornell in 1964, he explored the nature of scientific knowledge. Why do the laws of physics take the mathematical forms they do? Why is the universe comprehensible at all? What does it mean to understand something?

He didn't claim to have final answers. But he had wonderful questions, and a way of articulating the strangeness of our situation—conscious beings made of atoms, trying to understand the rules that govern atoms, discovering that those rules are bizarre beyond anything common sense could have prepared us for.

The Final Years

Feynman was diagnosed with a rare form of abdominal cancer in 1978. He had surgery, recovered, and continued working for another decade. In 1987, the cancer returned. He had more surgery, more complications. By early 1988, his kidneys were failing.

He refused dialysis. The treatment would have extended his life, but the quality of that life would have been poor. He was ready to go.

Richard Feynman died on February 15, 1988, at the age of sixty-nine. His last words, reportedly, were: "I'd hate to die twice. It's so boring."

Even at the end, he couldn't resist the joke.

Legacy

Feynman left behind a transformed physics. His path integral formulation is now fundamental to quantum field theory, the framework underlying our best understanding of particle physics. His diagrams are the universal language of the field. His work on quantum electrodynamics showed that the strange rules of quantum mechanics could be tamed, calculated with, used to make predictions of staggering precision.

He also left behind something harder to quantify: an approach to science, and to life. Ask questions. Don't accept arguments from authority. If you can't explain something simply, you don't understand it well enough. Pay attention to what's actually there, not what you expect to be there. Treat the universe as a puzzle to be enjoyed, not a test to be passed.

And always, always, be willing to say: "I don't know. Let's find out."