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13 Facts About Physicist Niels Bohr

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Baron/Getty Images

Quantum physics might not be the most approachable topic, but there’s a good chance you’ve heard of some of its elemental parts, like atoms. In the early 20th century, Danish physicist Niels Bohr discovered the basic atomic structure—a positively charged nucleus surrounded by orbiting electrons—which laid the groundwork for how we understand atoms today. Here are 13 things you might not have known about Bohr.

1. HIS FATHER WAS NOMINATED FOR NOBEL PRIZES THREE TIMES IN TWO YEARS.

Niels Bohr, born in Copenhagen in 1885, was brought up in a family that valued science. His father Christian was a physiology professor at the University of Copenhagen, and he often hosted fellow scientists at his home for lively discussions. Young Niels and his two siblings often listened in, which likely inspired the young student’s future studies. Though he never won, Christian Bohr was nominated for the Nobel Prize by one colleague in 1907 and by two in 1908, all for his research on the physiology of respiration.

2. NIELS BOHR WAS A STELLAR STUDENT BUT A MEDIOCRE WRITER.

Bohr enrolled at the Gammelholm Latin School at age 7 and did well in all of his classes except for composition. According to the Niels Bohr Institute at the University of Copenhagen, he once turned in an essay that contained just two sentences: "A trip in the harbor: My brother and I went for a walk in the harbor. There we saw ships land and leave."

But by secondary school, he was correcting errors that he discovered in his physics textbooks. He excelled in the majority of his studies, and he graduated first in his class. Later in life, he penned a number of philosophical writings on physics, having overcome his youthful aversion to exposition.

3. HE SET OFF EXPLOSIONS IN HIS UNIVERSITY'S CHEMISTRY LAB.

Bohr began his university studies in 1903 at the same institution that employed his father, the University of Copenhagen. While he initially studied mathematics and philosophy, he won a physics competition sponsored by the Royal Danish Academy of Sciences, and he soon changed his major to physics. Bohr studied other fields, including inorganic chemistry, perhaps less successfully: He earned a reputation for causing explosions in the lab, and eventually broke a record amount of glass at the school. He would, however, go on to earn a master’s degree in 1909 and a doctorate in 1911 in physics.

4. BOHR DISAGREED WITH HIS PROFESSOR’S “PLUM PUDDING” THEORY.

After graduating, Bohr continued his studies at Cambridge University under J.J. Thomson, who had discovered the electron in 1897. Thomson had turned his attention to cathode rays, which were then believed to be part of the ether—a theoretical, weightless substance found everywhere in the universe. But he eventually determined that the rays were actually particles even smaller than the atom by showing that they could be deflected by electricity. This led Thomson to propose the “plum pudding” structure of atoms, in which negatively charged electrons are embedded in a sphere of positively charged matter, like raisins in a English pudding. Bohr would later contradict the “plum pudding” structure with his atomic model.

5. BOHR NAILED THE TRUE STRUCTURE OF AN ATOM IN 1913.

After finding his work at odds with Thomson’s, Bohr joined the Manchester University lab of Ernest Rutherford, who had also studied under Thomson. Rutherford had discovered the atomic nucleus through an experiment in which he shot alpha particles at a thin sheet of gold foil. Because some of the particles bounced back instead of going through the gold, he determined the majority of the atom’s mass must be within a small, central nucleus, with the electrons orbiting around it.

This became the foundation of his work with Bohr. The pair studied the structure of the atom, and Bohr determined Rutherford’s model must not be entirely correct. By the laws of physics, the orbiting electrons should eventually crash into the nucleus and destabilize the atom. Bohr eventually tweaked Rutherford’s model by explaining that the electrons orbiting a positively charged nucleus can jump between energy levels, which stabilizes the atoms.

6. HE FOUNDED COPENHAGEN’S INSTITUTE FOR THEORETICAL PHYSICS.

Based on his atomic research, the University of Copenhagen hired Bohr as a professor of theoretical physics in 1916 when he was just 31 years old. Soon after, he began pushing for a new institute for his field, which would allow researchers from all over the world to collaborate with Danish scientists at a state-of-the-art facility. He was granted approval, and the institute opened in 1921 with Bohr serving as director. (His mathematician brother Harald, a former Olympic soccer player, would go on to open the university’s mathematical institute next door nine years later.) In 1965 the university renamed the facility the Niels Bohr Institute, and today more than 1000 staff and students work and study there.

7. BOHR WON THE NOBEL PRIZE AT THE SAME TIME—AND IN THE SAME FIELD—AS ALBERT EINSTEIN.

Bohr and Einstein were not only contemporaries; they were good friends who partook in a series of conversations on physics over the course of decades, most notably at the 1927 Solvay Conferences now known as the Bohr–Einstein Debates. They argued two very different positions regarding the observations of electrons behaving as a particle in some experiments and a wave in others, even though an electron shouldn’t be able to be both. Bohr theorized the concept of complementarity to explain the phenomenon—that is, something can be two things at once, but we can only observe one of those things at a time. In establishing a fundamental principle of quantum mechanics, Bohr argued that the act of observation of particles brings them into existence, which is known as the Copenhagen Interpretation.

Einstein, on the other hand, argued that particles exist whether or not we actively observe them. (Imagine a very complex version of the “if a tree falls in the forest” question.) Even with their opposing theories, both were awarded the Nobel Prize in Physics in 1922: Bohr for his atomic model, and Einstein for his work on the photoelectric effect (instead of his then-controversial theory of relativity). So how did the two physicists receive prizes for the same thing in the same year? Einstein was actually awarded the 1921 prize a year late, due to a technicality.

8. THE CARLSBERG BREWERY GAVE BOHR UNLIMITED FREE BEER.

Danish beer giant Carlsberg, known for having its own laboratories to promote the study of natural sciences as they related to brewing, invited Bohr to live in its honorary residence, a house near its production facilities given to a deserving artist, scientist, or writer for life. It had a tap connected directly to the brewery for free beer. In 1932, Bohr and his family moved in, and stayed for the next 30 years.

The sweet real estate deal was not Carlsberg’s first interaction with the scientist. The brewery’s foundation helped Bohr pay for his research in England and funded the Institute for Theoretical Physics.

9. BOHR HELPED JEWISH SCIENTISTS ESCAPE THE NAZIS—UNTIL HE TOO HAD TO FLEE.

As the Nazis overran Europe at the height of World War II, Bohr helped scientists escaping the regime in Germany by providing them with funding, lab space, and temporary homes in Copenhagen. Bohr himself was forced to flee in 1943 after the Nazis overtook his country—Bohr’s mother was Jewish, and his entire family was persecuted. They fled Denmark on a fishing boat bound for Sweden, then Bohr and his son Aage were smuggled to England in the empty bay of a British Mosquito bomber plane. In London, he consulted with the Canadian and British governments’ ultra-classified program to develop nuclear weapons, code-named Tube Alloys.

10. HE USED THE ALIAS “NICHOLAS BAKER.”

In 1939, American officials had learned that Germany was attempting to build an atomic bomb. Five years later, the U.S. government invited Bohr to work on the Manhattan Project, its top-secret program to develop uranium- and plutonium-based nuclear bombs with the purpose of forcing the Axis nations to surrender. For two years, Bohr collaborated with American and British physicists at Los Alamos National Laboratory in New Mexico, using the name Nicholas Baker as a cover. In 1944, he wrote to British Prime Minister Winston Churchill with a progress report:

“What until a few years ago might be considered as a fantastic dream is at present being realized within great laboratories and huge production plants secretly erected in some of the most solitary regions of the United States. There a larger group of physicists than ever before collected for a single purpose, working hand in hand with a whole army of engineers and technicians, are preparing new materials capable of an immense energy release, and are developing ingenious devices for the most effective use of these materials. […]

“One cannot help comparing the situation with that of the alchemists of former days, groping in the dark in their vain efforts to make gold. Today physicists and engineers are, on the basis of firmly established knowledge, controlling and directing violent reactions by which new materials far more precious than gold are built up, atom by atom.”

11. BOHR WANTED NUCLEAR SCIENCE USED FOR PEACE.

He was a staunch believer in sharing the science behind nuclear weapons—a view not taken by U.S. and British leaders. Returning to Denmark after the war, Bohr directed his atomic research toward developing sustainable power rather than weapons. He and several colleagues established Risø, a research laboratory with a modern particle accelerator dedicated to developing nuclear energy for peaceful purposes, in the 1950s.

At the same time, Bohr co-founded the European Center for Nuclear Research (CERN), which held conferences and conducted research at Bohr’s Institute for Theoretical Physics for its first five years, prior to moving to Geneva, Switzerland, in 1957. The center now houses the Large Hadron Collider, the world’s largest particle accelerator, which generates electrical fields to speed up the movement of atomic particles and uses magnets to direct their flow. The collisions of the particles reveal information about their properties. Using the Large Hadron Collider, a team of researchers first observed a new type of particle, the Higgs boson, in 2012.

12. HIS SON AAGE ALSO WON A NOBEL PRIZE.

Bohr’s life wasn’t just focused on his work—he was a family man, too. He married Margrethe Nørlund in 1912, and they had six sons, four of whom survived into adulthood. His son Aage would follow closely in his father’s footsteps, becoming not only a physicist, but also the director of the Institute of Theoretical Physics (after his father passed away in 1962) and winner of the 1975 Nobel Prize in Physics for his research into the structure of atomic nuclei. The Bohrs are one of six father-son pairs to have each won a Nobel Prize (Niels Bohr’s professor J.J. Thomson and his son George Paget Thomson are another).

13. AN ELEMENT IS NAMED AFTER HIM.

Bohr still contributed to physics after his death—in a way. In 1981, German researchers succeeded in creating a single atom of Element 107, isotope 262, the result of bombarding bismuth atoms with chromium atoms. They named it Bohrium. The highly radioactive element does not occur in nature and, so far, only a few atoms of it have ever been created in a lab.

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'Lime Disease' Could Give You a Nasty Rash This Summer
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A cold Corona or virgin margarita is best enjoyed by the pool, but watch where you’re squeezing those limes. As Slate illustrates in a new video, there’s a lesser-known “lime disease,” and it can give you a nasty skin rash if you’re not careful.

When lime juice comes into contact with your skin and is then exposed to UV rays, it can cause a chemical reaction that results in phytophotodermatitis. It looks a little like a poison ivy reaction or sun poisoning, and some of the symptoms include redness, blistering, and inflammation. It’s the same reaction caused by a corrosive sap on the giant hogweed, an invasive weed that’s spreading throughout the U.S.

"Lime disease" may sound random, but it’s a lot more common than you might think. Dermatologist Barry D. Goldman tells Slate he sees cases of the skin condition almost daily in the summer. Some people have even reported receiving second-degree burns as a result of the citric acid from lime juice. According to the Mayo Clinic, the chemical that causes phytophotodermatitis can also be found in wild parsnip, wild dill, wild parsley, buttercups, and other citrus fruits.

To play it safe, keep your limes confined to the great indoors or wash your hands with soap after handling the fruit. You can learn more about phytophotodermatitis by checking out Slate’s video below.

[h/t Slate]

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Why Eating From a Smaller Plate Might Not Be an Effective Dieting Trick 
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It might be time to rewrite the diet books. Israeli psychologists have cast doubt on the widespread belief that eating from smaller plates helps you control food portions and feel fuller, Scientific American reports.

Past studies have shown that this mind trick, called the Delboeuf illusion, influences the amount of food that people eat. In one 2012 study, participants who were given larger bowls ended up eating more soup overall than those given smaller bowls.

However, researchers from Ben-Gurion University in Negev, Israel, concluded in a study published in the journal Appetite that the effectiveness of the illusion depends on how empty your stomach is. The team of scientists studied two groups of participants: one that ate three hours before the experiment, and another that ate one hour prior. When participants were shown images of pizzas on serving trays of varying sizes, the group that hadn’t eaten in several hours was more accurate in assessing the size of pizzas. In other words, the hungrier they were, the less likely they were to be fooled by the different trays.

However, both groups were equally tricked by the illusion when they were asked to estimate the size of non-food objects, such as black circles inside of white circles and hubcaps within tires. Researchers say this demonstrates that motivational factors, like appetite, affects how we perceive food. The findings also dovetail with the results of an earlier study, which concluded that overweight people are less likely to fall for the illusion than people of a normal weight.

So go ahead and get a large plate every now and then. At the very least, it may save you a second trip to the buffet table.

[h/t Scientific American]

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