In 1999, Albert Einstein was named TIME’s Person of the Century. The father of special and general relativity, Einstein’s theories introduced concepts that would help make dozens of modern technologies possible. “I have no special talents,” Einstein once said, “I am only passionately curious.” Here are some facts about the physicist who gave us wild hair and E=MC^2.
1. When Albert Einstein was born, his misshapen head terrified the room.
On March 14, 1879, baby Einstein emerged with a “swollen, misshapen head and a grossly overweight body,” according to Denis Brian’s book, Einstein: A Life. When she got a look at him later, his grandmother was terrified of the chunky child. She screamed, “Much too fat! Much too fat!” Thankfully, Albert would eventually grow into his body. (However, he did have trouble developing in other arenas: He supposedly didn’t start speaking until the age of 2.)
2. As a child, he was the king of throwing temper tantrums.
The young genius had a habit of throwing objects whenever he was displeased; once, a frustrated Einstein even threw a chair at his teacher. The 5-year-old enjoyed bombarding his tutors and family members: His sister Maja, who was often conked in the head by Einstein’s fusillades, later quipped, “It takes a sound skull to be the sister of an intellectual.”
3. Einstein did not struggle in school.
The idea that Einstein had trouble in school is a myth. During summers, a pre-teen Einstein would study mathematics and physics for fun, eventually mastering differential and integral calculus by age 15. But that’s not to say he was a perfect student. Einstein hated rote learning and refused to study subjects that didn’t interest him. So, naturally, when the obstinate number-lover took the entrance exam to the polytechnic school in Zurich, he flunked the language, zoology, and botany sections.
4. Nobody knows Einstein’s IQ.
Einstein’s IQ was never tested, though that hasn’t stopped people from guessing. Lots of websites claim the physicist’s IQ was 160, but there’s simply no way of verifying that claim. “One fundamental problem with the estimates I’ve seen is that they tend to conflate intellectual ability with domain-specific achievement,” Dean Keith Simonton, professor emeritus of psychology at the University of California, Davis told Biography. For all we know, Einstein’s aptitude in arenas outside of physics might have rivaled that of an average Joe.
5. He refreshed his brain by playing the violin.
Whenever Einstein needed to relax, he turned to music. He started violin lessons at age 5 and, at around 17, impressed his teachers at cantonal school with his playing during a music exam. Around 1914, when Einstein lived in Berlin, he played sonatas with his friend and fellow theoretical physicist, Max Planck. And after he became famous, Einstein would play a handful of benefit concerts alongside greats like Fritz Kreisler. “Music helps him when he is thinking about his theories,” his second wife, Elsa, said. “He goes to his study, comes back, strikes a few chords on the piano, jots something down, returns to his study.”
6. Fashion was not Einstein’s strong suit.
Einstein hated wearing socks and was immensely proud of the fact that he didn’t have to wear them while giving lectures at Oxford in the 1930s. His antipathy apparently stemmed from a childhood realization: “When I was young I found out that the big toe always ends up making a hole in a sock,” Einstein reportedly said. “So I stopped wearing socks.” As an adult, he typically wore an undershirt, baggy trousers held by rope, and a pair of (occasionally women’s) sandals.
7. He loved sailing (and was absolutely terrible at it).
While an undergraduate in Zurich, Einstein fell in love with sailing—a passion that would persist throughout his life. There was just one problem: He was a horrible sailor. He regularly tipped his boat over and required rescue dozens of times. (His sailboat was named Tinef, Yiddish for “worthless.”) In 1935, The New York Times reported on Einstein’s sailing misadventures with the punny headline: “Relative Tide and Sand Bars Trap Einstein.”
8. Fatherhood gave Einstein his iconic hair.
As a young man, Einstein sported a well-maintained head of dark hair—that is, until his son Hans was born in 1904. Like many new parents, Einstein discovered that having a new mouth to feed changed everything: The patent clerk was so busy trying to support his family that he stopped combing his hair and visiting the barber. Slowly, an iconic look was born.
Einstein would spurn barbers for the rest of his life. His wife Elsa would cut his mop whenever it became disheveled.
9. He had a habit of mindlessly gorging on food.
When Einstein was a patent clerk, he formed a book club with two friends and called it the “Olympia Academy.” The trio usually dined on sausages, Gruyère cheese, fruit, and tea. But on Einstein’s birthday, his friends brought expensive caviar as a surprise. Einstein, who had a knack for mindlessly eating when talking about something he was passionate about, began stuffing his face while discussing Galileo’s principle of inertia—totally unaware of what he was eating. He later offered this excuse: “Well, if you offer gourmet foods to peasants like me, you know they won’t appreciate it.”
10. He had a bawdy sense of humor.
Einstein enjoyed the occasional dirty joke. When he accepted his first job as a professor, he said, “[N]ow I too am an official member of the guild of whores.” And when a member of his book club gave him a nameplate that said “Albert, Knight of the Backside,” Einstein proudly kept it tacked on his apartment door. Later in life, he’d tell jokes to his pet parrot, Bibo. (Einstein believed the bird was depressed and needed a laugh.)
11. He loved the famous tongue photo.
On his 72nd birthday, Einstein was leaving an event held in his honor. As he was getting into his car, photographers asked him to smile for the camera. Einstein, however, was sick and tired of grinning for a photograph—he’d been doing it all evening—so he popped his tongue out instead. Einstein liked the photo so much, he put it on his greeting cards.
12. He was an inventor.
Having spent seven years working in the Swiss patent office, Einstein was naturally curious about inventing and secured approximately 50 patents during his lifetime. He enjoyed tinkering with electronics and eventually patented a self-adjusting camera, a refrigerator that could last 100 years, and even a blouse.
13. When it came to love, Einstein was no genius.
Einstein, who married twice, had multiple extramarital affairs—including one dalliance with a possible Russian spy. His first marriage with Mileva Marić, a physicist he met at the Swiss Polytechnic School, soured after the birth of their third child. As their marriage crumbled, Einstein imposed a list of brusque—if not cruel—demands which included: “You will obey the following points in your relations with me: 1. You will not expect intimacy from me … 2. You will stop talking to me if I request it.” Unsurprisingly, they divorced. Later, Einstein married his cousin, Elsa Löwenthal.
14. A letter Einstein signed helped spark the Manhattan Project.
Einstein was not part of the Manhattan Project, but he was instrumental in getting it started. In the late 1930s, German scientists discovered nuclear fission of uranium, a major step toward the development of the atomic bomb. Much of the world’s uranium was held in the Congo—then a colony of Belgium—so two Hungarian-American physicists named Leo Szilard and Eugene Wigner decided to get Einstein to write a letter to his friend, the queen of Belgium. Einstein suggested a letter to a Belgian minister instead, but an encounter with an economist who knew President Franklin D. Roosevelt resulted in a change in direction and a letter that prompted America to start its own experiments.
15. He loved answering fan mail from children.
Einstein received countless letters from the public, but he always tried to answer mail sent by children. (In one letter, a young girl complained about her troubles with math. The professor supposedly wrote back, “Do not worry about your difficulty in mathematics. I can assure you mine are still greater.”) Einstein’s many correspondences with children—filled with charm and encouragement—are compiled in a book by Alice Calaprice called Dear Professor Einstein.
16. He turned down the presidency of Israel.
After the first president of the state of Israel, Chaim Weizmann, died in 1952, the prime minister asked Einstein to step into the (mostly ceremonial) role. The physicist declined, writing: “I am deeply moved by the offer from our state of Israel, and at once saddened and ashamed that I cannot accept it. All my life I have dealt with objective matters, hence I lack both the natural aptitude and the experience to deal properly with people and to exercise official functions.”
17. Einstein was an outspoken advocate for racial justice.
Having abandoned Germany in 1933 to avoid Nazi persecution, Einstein was sensitive to the racial discrimination he saw in the United States. He championed the rights of Black Americans and was a member of the NAACP. When the famed Black singer Marian Anderson came to perform at Princeton in 1937 and was denied a hotel room, Einstein invited her to stay in his home. He was also pen pals with W.E.B. Du Bois and, when Du Bois became the target of the Red Scare, Einstein effectively saved him by offering to be his character witness. In a 1946 speech he delivered at Pennsylvania’s Lincoln University, he called segregation “a disease of white people,” vowing, “I do not intend be quiet about it.”
18. He was the inspiration for Yoda.
Yoda’s face was partly modeled after Einstein’s. According to Star Wars special-effects artist Nick Maley, “a picture of Einstein ended up on the wall behind the Yoda sculptures and the wrinkles around Einstein’s eyes somehow got worked into the Yoda design. Over the course of this evolutionary process Yoda slowly changed from a comparatively spritely, tall, skinny, grasshopper kind of character into the old wise spirited gnome that we all know today.”
19. Einstein’s theories are more relevant than you might think.
It’s easy to assume that Einstein’s theories of relativity are purely theoretical, but they really do affect your everyday life. For instance, the theory of general relativity states that gravity affects time: Time moves by faster for objects in space than objects here on Earth. And that has profound implications for many space-based technologies, especially the accuracy of your GPS. His theories also explain how electromagnets work and are foundational to nuclear technology.