The Solvay Meetings and the Development of Quantum Physics

Niels Henrik David Bohr

David J. Gross, Marc Henneaux A, Alexander Sevrin

Antony Valentini

D.H. Delphenich

Alessio Rocci, Franklin Lambert

The meeting patronized by Ernest Solvay in 1911, the first Solvay Council, marked the beginning of what can be called the first quantum revolution. Maurice de Broglie was one of the secretaries of the Council. He participated in the two following conferences and contributed to the third Council with his work. Louis de Broglie collaborated and discussed with his elder brother. Departing from Maurice's achievements, Louis developed his approach to the wave-particle duality of light and extended it to other particles. He presented it at the fifth meeting in 1927. This paper investigates the connection between the two scientists and the Solvay Councils, arguing that this link was essential in developing the first quantum revolution, a process that ended, according to Werner Heisenberg, at the fifth Solvay Physics Council.

Andrew Walcott Beckwith

Largely drawn from “Quantum Theory at the Crossroads: Reconsidering the 1927 Solvay Conference” by Guido Bacciagaluppi and Antony Valentini, but also from several books by Pais (“Inward Bound” and “Subtle is the Lord”), plus other sources, we examine some of the very contemporary themes as to quantum measurement which were debated in the 5th Solvay meeting. In addition, we also discuss some issues given by Roland Omnes in “Understanding Quantum Mechanics” as to the problem of classical and quantum properties, which is at the forefront of the Quantum Gravity issues of how to reconcile semi classical physics with the presumed bridge between Planckian physics (presumably quantum in nature) with the rest of cosmology. The issues argued in part by the Solvay meeting as to Quantum measurements and the competing Pilot theory, as brought up by De Broglie, and how that plays out as to the later Hidden Variables and the alleged determinism foundations of an embedding structure for Quantum physics, still are with us, and make the Solvay meeting, 1927 a stellar event, still worth revisiting 90 years later.