First conference

Hendrik Lorentz was chairman of the first Solvay Conference on Physics, held in Brussels from 30 October to 3 November 1911.^[2] The subject was Radiation and the Quanta. This conference looked at the problems of having two approaches, namely classical physics and quantum theory. Albert Einstein was the second youngest physicist present (the youngest one was Lindemann). Other members of the Solvay Congress were experts including Marie Curie, Ernest Rutherford and Henri Poincaré (see image for attendee list).

Third conference

The third Solvay Conference on Physics was held in April 1921, soon after World War I. Most German scientists were barred from attending. In protest at this action, Albert Einstein, although he had renounced German citizenship in 1901 and become a Swiss citizen (in 1896, he renounced his German citizenship, and remained officially stateless before becoming a Swiss citizen in 1901),^[3][4] declined his invitation to attend the conference and publicly renounced any German citizenship again. Because anti-Semitism had been on the rise, Einstein accepted the invitation by Dr. Chaim Weizmann, the president of the World Zionist Organization, for a trip to the United States to raise money.^[5][6]

Fourth conference

The fourth Solvay Conference on Physics was held in 1924. These conferences, supported by the King of Belgium, had become the leading international gathering for the discussion of the very latest developments in physics. The subject was "The electrical conductivity of metals and related topics". Scientists based in Germany and Austria were not invited to this Solvay meeting due to the tensions still prevailing after the First World War. So there was no Planck, Einstein, Sommerfeld or Born.^[7]

Fifth conference

Perhaps the most famous conference was the fifth Solvay Conference on Physics, which was held from 24 to 29 October 1927. The subject was Electrons and Photons and the world's most notable physicists met to discuss the newly formulated quantum theory. The leading figures were Albert Einstein and Niels Bohr. Seventeen of the 29 attendees were or became Nobel Prize winners, including Marie Curie who, alone among them, had won Nobel Prizes in two separate scientific disciplines.^[8] The anti-German prejudice that had prevented Einstein and others from attending the Solvay conferences held after the First World War had melted away. Essentially all of those names who had contributed to the recent development of the quantum theory were at this Solvay Conference, including Bohr, Born, de Broglie, Dirac, Heisenberg, Pauli and Schrodinger. Heisenberg commented:^[9]

"Through the possibility of exchange between the representatives of different lines of research, this conference has contributed extraordinarily to the clarification of the physical foundations of the quantum theory. It forms, so to speak, the outward completion of the quantum theory."

A. Piccard, E. Henriot, P. Ehrenfest, E. Herzen, Th. De Donder, E. Schrödinger, J.E. Verschaffelt, W. Pauli, W. Heisenberg, R.H. Fowler, L. Brillouin;
P. Debye, M. Knudsen, W.L. Bragg, H.A. Kramers, P.A.M. Dirac, A.H. Compton, L. de Broglie, M. Born, N. Bohr;
I. Langmuir, M. Planck, M. Curie, H.A. Lorentz, A. Einstein, P. Langevin, Ch. E. Guye, C.T.R. Wilson, O.W. Richardson

Fifth conference participants, 1927. Institut International de Physique Solvay in Leopold Park.
Image

Participants per year

The following list of participants is extracted from the proceedings of the Solvay Conferences in Physics stored in the Solvay archives ^[11]

1948: (scientific committee - present) Sir Lawrence Bragg, Niels Bohr, Théophile de Donder, Sir Owen W. Richardson, Emile Verschaffelt, Hendrik Kramers (scientific committee - absent) Peter Debye, Abram Fedorovich Ioffé, Albert Einstein, Frédéric Joliot (speakers) C. F. Powell, P. Auger, Felix Bloch, Patrick Blackett, S. Bhabha, Marie-Antoinette Tonnelat on behalf of Louis de Broglie, Rudolf Peierls, Walter Heitler, Edward Teller, R. Serber, Léon Rosenfeld (additional participants) H. Casimir, J. Cockroft, P. Dee, Paul Dirac, Ferretti, O. Frisch, Oskar Klein, Leprince-Ringuet, Lise Meitner, Christian Moeller, Francis Perrin, Robert Oppenheimer, Wolfgang Pauli, P. Scherrer, Erwin Schroedinger (auditeurs) J. Timmermans, G. Balasse, J. Errera, O. Goche, P. Kipfer, L. Flamache, M. Occhialini, Marc de Hemptinne (secrétaires) E. Stahel, J. Géhéniau, Miss Dilworth, Ilya Prigogine, L. Groven, Léon Van Hove, Yves Goldschmidt, MM Van Styvendael, Demeur, Van Isacker (administrative commission) Jules Bordet, Ernest-John Solvay, Dr F. Héger-Gilbert, E. Henriot, F. van den Dungen.

Conferences on physics gallery

• 
  First Conference, 1911
• 
  Second Conference, 1913
• 
  Third Conference, 1921
• 
  Fourth Conference, 1924
• 
  Fifth Conference, 1927. 1st row : Langmuir, Planck, Madame Curie, Lorentz, Einstein, Langevin, Guye, Wilson, Richardson. 2nd row : Debye, Knudsen, W. L. Bragg, Kramers, Dirac, Compton, de Broglie, Born, Bohr. 3rd row : Piccard, Henriot, Ehrenfest, Herzen, de Donder, Schrodinger, Verschaffelt, Pauli, Heisenberg, Fowler, Brillouin.
• 
  Sixth Conference, 1930. 1st row: Th. de Donder, P. Zeeman, P. Weiss, A. Sommerfeld, M. Curie, P. Langevin, A. Einstein, O. Richardson, B. Cabrera, N. Bohr, W. J. De Haas; 2nd row: E. Herzen, E. Henriot, J. Verschaffelt, C. Manneback, A. Cotton, J. Errera, O. Stern, A. Piccard, W. Gerlach, C. Darwin, P. A. M. Dirac, H. Bauer, P. Kapitsa, L. Brillouin, H. A. Kramers, P. Debye, W. Pauli, J. Dorfman (ru), J. H. Van Vleck, E. Fermi, W. Heisenberg^[12]
• 
  Seventh Conference, 1933
• 
  Eighth Conference, 1948
• 
  Ninth Conference, 1951
• 
  Tenth Conference, 1954

Conferences on chemistry gallery

• 
  First Conference, 1922

1902-1910

H. A. Lorentz (1902), P. Zeeman (1902) - M. Curie (1903), S. Arrhenius (1903) - Lord Rayleigh (1904) - J. J. Thomson (1906) - A. A. Michelson (1907) - E. Rutherford (1908) - J. D. van der Waals (1910)

1911-1920

W. Wien (1911) - V. Grignard (1912) - H. Kamerlingh Onnes (1913) - M. von Laue (1914) - W. H. Bragg (1915), W. L. Bragg (1915) - C. G. Barkla (1917) - M. Planck (1918) - J. Stark (1919) - W. Nernst (1920)

1921-1930

A. Einstein (1921), F. Soddy (1921) - N. Bohr (1922), F. W. Aston (1922) - K. M. Siegbahn (1924) - J. Franck (1925), G. Hertz (1925) - J. Perrin (1926) - A. H. Compton (1927), C. T. R. Wilson (1927), H. Wieland (1927) - O. Richardson (1928) - L. de Broglie (1929)

1931-1940

W. Heisenberg (1932), I. Langmuir (1932) - P. A. M. Dirac (1933), E. Schrödinger (1933) - J. Chadwick (1935), F. Joliot-Curie (1935), I. Curie (1935) - W. Debije (1936) - E. Fermi (1938), R. Kuhn (1938) - E. Lawrence (1939), L. Ruzicka (1939)

1941-1950

G. de Hevesy (1943) - W. Pauli (1945) - P. Bridgman (1946) - P. Blackett (1948)

1951-1954

J. D. Cockcroft (1951), E. T. Walton (1951) - M. Born (1954), W. Bothe (1954).