13 Facts About Physicist Niels Bohr

Baron/Getty Images
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.

Amazon's Best Black Friday Deals: Tech, Video Games, Kitchen Appliances, Clothing, and More

Amazon
Amazon

This article contains affiliate links to products selected by our editors. Mental Floss may receive a commission for purchases made through these links.

Black Friday is finally here, and Amazon is offering great deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40)

- Keurig K-Cafe Special Edition; $190 (save $30)

- Ninja OS301 Foodi 10-in-1 Pressure Cooker and Air Fryer; $125 (save $75)

- Nespresso Vertuo Next Coffee and Espresso Machine by Breville; $120 (save $60)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75)

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $80 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10)

- Longzon Silicone Stretch Lids - Set of 14; $16 (save $11)

- HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

- Oscillating Quiet Cooling Fan Tower; $59 (save $31)

- TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

- Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

- Ring Video Doorbell; $70 (save $30)

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- The Legend of Zelda: Link's Awakening; $40 (save $20)

- Hyrule Warriors: Age of Calamity; $50 (save $10)

- Marvel's Avengers; $25 (save $33)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

- BioShock: The Collection; $20 (save $30)

- The Sims 4; $24 (save $20)

- God of Warfor PlayStation 4; $10 (save $10)

- Days Gonefor PlayStation 4; $20 (save $6)

- Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250)

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Apple iPad Mini (64 GB); $335 (save $64)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $120 (save $79)

- Seneo Wireless Charger, 3 in 1 Wireless Charging Station; $16 (save $10)

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

- MACTREM LED Ring Light 6" with Tripod Stand; $16 (save $3)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

- DR. J Professional HI-04 Mini Projector; $93 (save $37)

Headphones and speakers

Beats/Amazon

- Beats Solo3 Wireless On-Ear Headphones; $120 (Save $80)

- Apple AirPods Pro; $169 (save $50)

- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Powerbeats Pro Wireless Earphones; $175 (save $75)

- JBL Boombox; $280 (save $120)

Movies and TV

HBO/Amazon

- Game of Thrones: The Complete Series; $115 (save $89)

- Jurassic World 5-Movie Set; $23 (save $37)

- Deadwood: The Complete Series; $42 (save $28)

- Back to the Future Trilogy; $15 (save $21)

Toys and Games

Amazon

- Awkward Family Photos Greatest Hits; $15 (save $10)

- Exploding Kittens Card Game; $10 (save $10)

- Cards Against Humanity: Hidden Gems Bundle; $14 (save $5)

- LOL Surprise OMG Remix Pop B.B. Fashion Doll; $29 (save $6)

- LEGO Ideas Ship in a Bottle 92177 Expert Building Kit; $56 (save $14)

Furniture

Casper/Amazon

- Casper Sleep Element Queen Mattress; $476 (save $119)

- ZINUS Alexis Deluxe Wood Platform Bed Frame; $135 (save $24)

- ROMOON Dresser Organizer with 5 Drawers; $59 (save $11) 

- AmazonBasics Room Darkening Blackout Window Curtains; $26 (save $5)

- Writing Desk by Caffoz; $119 (save $21)

- SPACE Seating Office Support Managers Chair; $112 (save $116)

- Rivet Globe Stick Table Lamp; $53 (save $17)

- Christopher Knight Home Merel Mid-Century Modern Club Chair; $188 (save $10)

- Walker Edison Furniture Industrial Rectangular Coffee Table; $121 (save $48)

Beauty

Haus/Amazon

- MySmile Teeth Whitening Kit with LED Light; $21 (save $12) 

- Cliganic USDA Organic Lip Balms Set of Six; $6 (save $4)

- HAUS LABORATORIES By Lady Gaga: LE RIOT LIP GLOSS; $7 (save $11)

- Native Deodorant for Men and Women Set of Three; $25 (save $11) 

- BAIMEI Rose Quartz Jade Roller & Gua Sha; $14 (save $3)

- Honest Beauty Clearing Night Serum with Pure Retinol and Salicylic Acid; $20 (save $8)

- WOW Apple Cider Vinegar Shampoo and Hair Conditioner Set; $30 (save $5) 

- La Roche-Posay Effaclar Purifying Foaming Gel Cleanser; $15 (save $5)

- wet n wild Bretman Rock Shadow Palette; $9 (save $6)

- EltaMD UV Daily Tinted Face Sunscreen Moisturizer with Hyaluronic Acid; $25 (save $6)

Clothes

Ganni/Amazon

- Ganni Women's Crispy Jacquard Dress; $200 (save $86) 

- The Drop Women's Maya Silky Slip Skirt; $36 (save $9)

- Steve Madden Women's Editor Boot; $80 (save $30)

- adidas Women's Roguera Cross Trainer; $40 (save $25)

- Line & Dot Women's Elizabeth Sweater; $74 (save $18)

- Levi's Men's Sherpa Trucker Jacket; $57 (save $41)

- Adidas Men's Essentials 3-Stripes Tapered Training Joggers Sweatpants; $28 (save $12)

- Timex Men's Weekender XL 43mm Watch; $32 (save $20)

- Ray-Ban Unisex-Adult Hexagonal Flat Lenses Sunglasses; $108 (save $46) 

- Reebok Men's Flashfilm Train Cross Trainer; $64 (save $16)

Sign Up Today: Get exclusive deals, product news, reviews, and more with the Mental Floss Smart Shopping newsletter!

How Much Is the Earth Worth?

The New York Public Library, Unsplash
The New York Public Library, Unsplash

Our home planet may be the most precious place we know, but it isn't priceless. The Earth's resources and the value it offers to humans add up to some unknown, tangible cost. The species may never have to worry about buying or selling the world, but thinking of it in terms of concrete numbers can help us better understand its value. Now, as Treehugger reports, one scientist has developed a special formula that allows us to do just that.

According to the calculations of Greg Laughlin, an assistant astronomy and astrophysics professor from the University of California, Santa Cruz, the Earth is worth roughly $5 quadrillion (or $5,000,000,000,000,000). He came up with that price after gauging the planet's mass, temperature, age, and other factors that directly correlate to its ability to sustain life.

To emphasize just how valuable the Earth is, Laughlin also estimated the worth of other planets in our solar system. Our nearest neighbor Mars costs about the same as a used car at $16,000. That's a fortune compared to Venus, which he appraised at the meager value of one cent.

Laughlin doesn't expect these numbers to have applications in the real world. Rather, he hopes they will inspire people to better appreciate the only home they know. He's not the first person to put a massive, hypothetical price tag on something just for fun. The cost of the Death Star from Star Wars has been calculated at $852 quadrillion—many times Laughlin's estimate for Earth.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.