Apparently this picture is already popular all over the Internet, but I saw it for the first time a couple of weeks ago in my brother’s college physics text book. Anyways I decided to share it, the more the merrier!

Solvay conference 1927: The Greatest Minds of The Twentieth Century

Update [October 14 2014]: Found a colorized version of this image too!

The caption under the picture says the following:

“The “architects” of modern physics. This unique photograph shows many eminent scientists who participated in the Fifth International Congress of Physics held in 1927 by the Solvay Institute in Brussels. At this and similar conferences, held regularly from 1911 on, scientists were able to discuss and share the many dramatic developments in atomic and nuclear physics. This elite company of scientists includes fifteen Nobel prize winners in physics and three chemistry. (Photograph courtesy of AIP Neil Bohr Library)”

I also found a video of the event:

I will try to briefly summarize these scientist’s major contributions, just enough to appear smart in front of your friends but not all that geeky.

The scientists from left to right. Scientists with an asterisk beside there names are Nobel laureates:

Top row

1. Auguste Piccard (1884-1962): Is a Swiss physicist, inventor, and explorer. He had an avid interest in balloons and curious about the upper atmosphere of our earth. This led him to create a spherical, pressurized aluminum gandola that enabled him to reach very high altitudes. He broke the altitude record multiple times, stopping at 23,000 m. He then shifted his interest to the ocean when he realized that his techniques could be used to delve deep into the ocean. He and his son built the Bathyscaphe Trieste, which descended deep down the Mariana trench (10,900 m) near Guam in 1960. This achievement was never repeated, and currently no manned or unmanned craft exists capable of matching this record.

2. Émile Henriot (1885-1961): Is a French chemist that showed Potassium and Rubidium are naturally radioactive. Also, his work on angular velocities was later used to create ultracentrifuges. He obtained his DSc in physics from the Sorbonne under Marie Currie.

3. Paul Ehrenfest(1880-1933): Is an Austrian physicist and mathematician. His major contributions include the theory of adiabatic invariant. He also had major contributions in quantum physics including the theory of phase transitions and the Ehrenfest theorem. The Ehrenfest Paradox is also named after him. Ehrenfest was a close friend to Albert Einstein and Niels Bohr and their visits to each other and debates are well documented. Ehrenfest committed suicide in 1933 after a long fight with depression. (I know that was way too geeky, even for me, but what can I do? He was probably as geeky as they come !)

4. E. Herzen: Nothing much comes up in Google about Herzen, most results are about this picture. If you know anything about him, please do tell.

5. Théophile de Donder (1872-1957): Is a Belgian thermodynamicist, mathematician, and physicist. He is considered to be the father of thermodynamics of irreversible process. His works was later developed by Nobel prize winner Illya Prigogin. de Donder was a friend and associate of Albert Einstein.

6. Erwin Schrödinger (1887-1961): Is an Austrian physicist, who proposed the Schrödinger Equation which propelled him to fame. This equation plays an important part in nanoscopic particles analogous to Newton’s second law in classical mechanics. The paper proposing this equation is celebrated as one of the greatest achievements in the 20th century. His works later helped in discovering DNA structure and how genetic information may be stored in molecules. Schrödinger has a huge crater on the far side of the moon named after him posthumously.

7. Jules-Émile Verschaffelt (1870-1955): Is a Belgian physicist, he published almost 300 papers on topics of thermodynamics, capillarity, thermochemistry and irreversibility.

8. Wolflfgang Pauli (1900-1958): Is an Austrian theoretical physicist who is known for his work on theory of spin and the exclusion principle which explains the structure of matter. This principle explains a wide range of physical phenomena, such as rigidness or stiffness of matter.

9. Werner Karl Heisenberg (1901-1976): Is a German physicist and a Nobel laureate and considered one of the founding fathers of quantum mechanics and acknowledged as one o the most important physicists in the twentieth century. Heisenberg’s career was marred with controversy and debate because of his position as the head of the German nuclear program under the Nazi regime. Did he have a moral dilemma with with the nuclear program? Did he purposely try to hinder the advancement of the program? Or did he just make overestimation errors? Did he attempt to paint the “moral qualms” picture of the war? Are all questions that are debated up to today. He and Bohr developed the uncertainty principle which tries to answer the question: How does one measure the location of an electron around a nucleus? Their principle was furiously challenged by Einstein and debated.

10. Sir Ralph Fowler (1889-1944): Is a British physicist and astronomer. He wrote with Arthur Milne seminal work on stellar spectra, temperatures and pressures. He was made a fellow member of the Royal Society in 1925. Fowler supervised 15 fellows of the Royal society and 3 Nobel Laureates, most notably Paul Dirac.

11. Leon Brilloun (1889-1969): Is a French physicist who is considered to be the founder of modern solid state physics of which he contributed with the discovery of the Brilloun zones among other things. Brilloun coined the concept of negentropy (negative entropy) which was introduced by Schrödinger.

Middle Row

12. Peter Debye (1884-1966): Is a Dutch physical chemist, his major achievements include: application of the concept of dipole moment to the charge distribution in asymmetric molecules in 1912, the extension of Einstein’s theory of specific heat, the extension of Bohr’s atomic structure theory, and worked on dipole moments and X-ray diffraction which awarded him the Nobel prize in chemistry.

13. Martin Knudsen (1871-1949): Is a Danish physicist who is primarily known for his work molecular gas flow. He was renown for his work on kinetic-molecular theory. Knudsen gas, Knudsen number, and Knudsen cell are all named after him. Knudsen also was interested in oceanography and studying the properties of saltwater.

14. William Lawrence Bragg (1890-1971): Is an Australian physicist. Bragg is most famous for “Bragg’s Law”, which makes it possible to calculate the positions of the atoms within a crystal from the way in which an X-ray beam is diffracted by the crystal lattice. Along with his fatherSir William Henry Bragg, this law helped father and son determine the molecular structure of NaCl, ZnS, and diamond, which consequently lead to awarding them the Nobel prize. His X-ray method helped Francis Crick and James Watson discover the structure of DNA. William Bragg is the youngest person to win the Nobel prize, at the young age of only 25!

15. Hendrik Kramers (1894-1952): Is a Dutch physicist. He worked under Bohr, where he did most of his dissertation on intensities of atomic transition. However, his formal PhD was obtained in Leiden. Hendrik was one of the founders of the National Research Institute for Mathematics and Computer Science in Holland. The Kramer’s crater on the moon is named after him.

16. Paul Dirac (1902-1984): Is a British theoretical physicist. He is considered a founder of quantum mechanics and quantum electromechanics. His “ Principles of Quantum Mechanics” which was published in 1930, is considered a landmark in science, and was quickly adopted by textbooks about the subject up to this day. in 1933, he was awarded the Nobel prize along with Schrödinger for the discovery of “new productive forms of atomic theory.” Dirac is considered by many physicist as the greatest physicist in the 20th century, even more than Albert Einstein!

17. Aurthur Holly Compton (1892-1962): Is an American physicist who is known for his discovery of the “Compton Effect” which earned Compton the Nobel prize. The discovery of the Compton effect later helped in lots of different fields such as radiobiology, radiation therapy, and astrophysics. In 1941, Compton helped take over the then stagnant American atomic program and appointed Robert Oppenheimer (the father of the atomic bomb) as the committee’s top theorist. Throughout the war, Compton was an important scientific adviser and administrator.

18. Louis de Broglie (1892-1987): is a French physicist. He introduced the de Broglie hypothesis, which states that any moving particle or object has an associated wave. Thus creating a new field in physics called wave mechanics. For this he won the Nobel prize for physics in 1929. One very important application of his hypothesis is the electron megascope.

19. Max Born (1882-1970): Max Born is a German physicist. He is considered one of the founders of quantum mechanics. He formulated the now standard probability density function in which he received a Nobel 30 years later in 1954. He was also nominated by Einstein for another Nobel prize in 1928 for his work with Heisenberg and Jordan for their works on “for the creation of quantum mechanics, the application of which has, inter alia, led to the discovery of the allotropic forms of hydrogen”, however the Nobel prize went to Heisenberg alone, with no credit to Born or Jordan which caused somewhat of a controversy. Max Born also the grandfather of Australian singer Olivia Newton John.

20. Niels Bohr (1885-1962): This scientist is my favorite for more than one reason. Bohr is a Danish physicist who’s work gives us the basic understanding we have today about atoms and how they work. He introduced the theory of electrons orbiting around a nucleus, and that the chemical properties of elements depended on the number of electrons. He also introduced the idea of electrons dropping from higher energy orbits to lower ones, emitting photons. This is the basis of quantum theory. For this, Bohr received the Nobel prize in 1922, his son, Aage, also won the Nobel prize in 1975. Niels worked in the Manhattan Project, but believed that the atomic secrets of that project should be shared with Russia and the international community. However Churchill disagreed with Bohr and later wrote in a letter “It seems to me Bohr ought to be confined or at any rate made to see that he is very near the edge of mortal crimes.” Finally, Niels was passionate football (soccer) player, who played as a goalkeeper in 1905 for the Danish club Akademisk Boldklub. In one instance playing against a German club, a German player shot a long ball towards the Danish goal, Niels was leaning against the goalpost, but he didn’t move a muscle and conceded a goal! Later Niels confessed that he was thinking about a mathematical problem that interested him much more than the dull game being played on the pitch! Now you know why I love this guy??

Bottom Row

21. Irving Langmuir (1881-1957): Is an American physicist and chemist from Brooklyn, New York. He invented the incandescent lamp, and won the Nobel prize for his work on surface chemistry. Langmuir coined the name “plasma” for ionized gas, because it reminded him of blood plasma. He also worked on improving sonar for submarine detection and later developed effective smoke screens and techniques de-icing of aircraft wings. 22. Max Planck (1858-1947): Is a German physicist who is considered to be THE father of quantum theory. In 1900 he proposed that the “electromagnetic energy could be emitted only in quantized form” or E=hv, where h is Planck’s constant. This is regarded as the birth of quantum physics and the greatest achievement of Planck. This achievement was recognized when Planck won the Nobel prize in 1918.

23. Marie Curie (1867-1934): Is a Polish physicist and chemist. With her husband Pierre Curie she studied radioactive material leading to the discover of polonium, which she named in honor of her native country, and radium. She was awarded the Nobel prize in physics in 1903 for “in recognition of the extraordinary services they have rendered by their [Henri Becquerel and Pierre Curie] joint researches on the radiation phenomena discovered by Professor Henri Becquerel.” She was awarded the prize in chemistry 8 years later “in recognition of her services to the advancement of chemistry by the discovery of the elements radium and polonium, by the isolation of radium and the study of the nature and compounds of this remarkable element”. She was the first woman to win this prestigious prize, she also remains the only woman to win the prize twice, and the only person to win the prize twice in two difference sciences!!

24. Hendrik Lorentz (1853-1928): Is a Dutch physicist who won the Nobel prize in 1902 for his work with Pieter Zeeman for the discovery of the Zeeman effect. Lorentz developed tools that are central to the theory of special relativity, that Einstein developed later. Lorentz was the chairman of the first Solvay conference in 1911. He never fully accepted quantum theory, and always hoped that it could be incorprated back into classical physics.

25. Albert Einstein (1879-1955): So you think you got this fella all figured out? E= mc^2 right? Wrong! Think again! Although this equation is one of Einstein’s main contribution, he has many many other theories, equations and discoveries. In fact Einstein won the Nobel prize in 1921 mainly for the discovery of the law of photoelectric effect. While many scientists contributed to understanding this effect, Einstein’s discovery laid the final building block to fully understand it. The understanding of this effect helped us in many applications, such as solar cells, night vision devices, and electroscopes. Albert Einstein has more than 50 papers and book. Einstein was named by Times magazine as the “Person of the Century” in 1999. Other contributions of Einstein include the special and general relativity theories, statistical mechanics and their application to quantum theory, an explanation of the Brownian movement of molecules,and atomic transition probabilities among others.

26. Paul Langevin (1872-1946): Is a French physicist who studied under Marie Currie and got his PhD from her in the Sorbonne. He is known for his work paramagnetism and diamagnetism. He also worked on methods for ultrasound for submarine detection, however WWI was over already when he had a fully operational system. It is reported that he had an affair with Marie Curie after her husband’s death (I know you like the dirty juice). Langevin was a staunch Nazi opposer which caused his job during the Nazi occupation of France.

27. C.E Guye: Amazingly I also couldn’t find anything about this guy (or perhaps just shoddy research work). If anybody knows anything about him, please let me know.

28. Charles Thomson Wilson (1869-1959): Is a Scottish physicist who had a special interest in meteorology. He observed cloud formations and tried to reproduce this effect on a smaller scale in a chamber. He then experimented in creation of cloud trails in his chamber caused by ions and radiation. He received a Nobel prize in 1927 for creating the [cloud chamber](http://en.wikipedia.org/wiki/Cloud_chamber “Cloud chamber”). The Wilson crater is co-named after him.

29. Owen Willans Richardson (1879-1959): Is a British physicist and a professor in Princeton University. He won the Nobel prize for physics in year in 1928 “for his work on the thermionic phenomenon and especially for the discovery of the law named after him”.

Whoa! You went through all that? Or you just feeling “scroll” happy today? Scroll back up and learn a thing or two!

Finally I would like to thank my little brother (33t) for showing me this picture and scanning it for me. And of course Wikipedia which made my research easier by the tenfold. Do the right thing DONATE!!