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Cambridge University Press eBooks

Quantum Theory at the Crossroads

Guido Bacciagaluppi, Antony Valentini

Published Oct 22, 2009• 425 citations
Publisher

Abstract

The 1927 Solvay conference was perhaps the most important in the history of quantum theory. Contrary to popular belief, questions of interpretation were not settled at this conference. Instead, a range of sharply conflicting views were extensively discussed, including de Broglie's pilot-wave theory (which de Broglie presented for a many-body system), Born and Heisenberg's 'quantum mechanics' (which apparently lacked wave function collapse or fundamental time evolution), and Schrödinger's wave mechanics. Today, there is no longer a dominant interpretation of quantum theory, so it is important to re-evaluate the historical sources and keep the debate open. This book contains a complete translation of the original proceedings, with essays on the three main interpretations presented, and a detailed analysis of the lectures and discussions in the light of current research. This book will be of interest to graduate students and researchers in physics and in the history and philosophy of quantum theory.

DOI
10.1017/cbo9781139194983

Related papers

Quantum Theory at the Crossroads: Reconsidering the 1927 Solvay Conference

Guido Bacciagaluppi, Antony Valentini

We reconsider the crucial 1927 Solvay conference in the context of current research in the foundations of quantum theory. Contrary to folklore, the interpretation question was not settled at this conference and no consensus was reached; instead, a range of sharply conflicting views were presented and extensively discussed. Today, there is no longer an established or dominant interpretation of quantum theory, so it is important to re-evaluate the historical sources and keep the interpretation debate open. In this spirit, we provide a complete English translation of the original proceedings (lectures and discussions), and give background essays on the three main interpretations presented: de Broglie's pilot-wave theory, Born and Heisenberg's quantum mechanics, and Schroedinger's wave mechanics. We provide an extensive analysis of the lectures and discussions that took place, in the light of current debates about the meaning of quantum theory. The proceedings contain much unexpected material, including extensive discussions of de Broglie's pilot-wave theory (which de Broglie presented for a many-body system), and a "quantum mechanics" apparently lacking in wave function collapse or fundamental time evolution. We hope that the book will contribute to the ongoing revival of research in quantum foundations, as well as stimulate a reconsideration of the historical development of quantum physics. A more detailed description of the book may be found in the Preface. (Copyright by Cambridge University Press (ISBN: 9780521814218).)

arXiv:quant-ph/0609184•Sep 24, 2006•355 citations

The “completion of quantum mechanics” —the fifth Solvay Conference on Physics, October 1927

Robert Golub, S. K. Lamoreaux

Abstract This conference was lauded by Heisenberg as, “officially, the completion of the quantum theory,” while Langevin remarked it was, “where the confusion of ideas reached its peak.” The conference was held just as the theory had reached maturity, only two years after Heisenberg’s matrix mechanics was invented. De Broglie argued for his pilot wave theory, which was shot down by Pauli using an incorrect argument and in later years was re-introduced as the de Broglie–Bohm theory. Heisenberg and Dirac debated the meaning of superposition and the “collapse” of the wave function. Bohr and Einstein engaged in their legendary debate. In the conference proceedings, we see the main contributors to the new theory attempt to come to terms with its enigmas.

•Feb 28, 2023•0 citations

Beyond the Quantum

Antony Valentini

At the 1927 Solvay conference, three different theories of quantum mechanics were presented; however, the physicists present failed to reach a consensus. Today, many fundamental questions about quantum physics remain unanswered. One of the theories presented at the conference was Louis de Broglie's pilot-wave dynamics. This work was subsequently neglected in historical accounts; however, recent studies of de Broglie's original idea have rediscovered a powerful and original theory. In de Broglie's theory, quantum theory emerges as a special subset of a wider physics, which allows non-local signals and violation of the uncertainty principle. Experimental evidence for this new physics might be found in the cosmological-microwave-background anisotropies and with the detection of relic particles with exotic new properties predicted by the theory.

•Jan 15, 2010•5 citations

Beyond the Quantum

Antony Valentini

At the 1927 Solvay conference, three different theories of quantum mechanics were presented; however, the physicists present failed to reach a consensus. Today, many fundamental questions about quantum physics remain unanswered. One of the theories presented at the conference was Louis de Broglie's pilot-wave dynamics. This work was subsequently neglected in historical accounts; however, recent studies of de Broglie's original idea have rediscovered a powerful and original theory. In de Broglie's theory, quantum theory emerges as a special subset of a wider physics, which allows non-local signals and violation of the uncertainty principle. Experimental evidence for this new physics might be found in the cosmological-microwave-background anisotropies and with the detection of relic particles with exotic new properties predicted by the theory.

arXiv:1001.2758•Jan 15, 2010•0 citations

History Lessons from the 5th Solvay Meeting, 1927

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.

Journal of High Energy Physics Gravitation and Cosmology•Jan 1, 2023•1 citation

History Lessons from the 5th Solvay Meeting, 1927

Andrew Walcott Beckwith

Largely drawn from “Quantum Theory at the Crossroads : Reconsideringthe1927 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.

•Aug 1, 2017•0 citations
The 1927 Solvay conference was perhaps the most important in the history of quantum theory. Contrary to popular belief, questions of interpretation were not settled at this conference. Instead, a range of sharply conflicting views were extensively discussed, including de Broglie's pilot-wave theory (which de Broglie presented for a many-body system), Born and Heisenberg's 'quantum mechanics' (which apparently lacked wave function collapse or fundamental time evolution), and Schrödinger's wave mechanics. Today, there is no longer a dominant interpretation of quantum theory, so it is important to re-evaluate the historical sources and keep the debate open. This book contains a complete translation of the original proceedings, with essays on the three main interpretations presented, and a detailed analysis of the lectures and discussions in the light of current research. This book will be of interest to graduate students and researchers in physics and in the history and philosophy of quantum theory.
We reconsider the crucial 1927 Solvay conference in the context of current research in the foundations of quantum theory. Contrary to folklore, the interpretation question was not settled at this conference and no consensus was reached; instead, a range of sharply conflicting views were presented and extensively discussed. Today, there is no longer an established or dominant interpretation of quantum theory, so it is important to re-evaluate the historical sources and keep the interpretation debate open. In this spirit, we provide a complete English translation of the original proceedings (lectures and discussions), and give background essays on the three main interpretations presented: de Broglie's pilot-wave theory, Born and Heisenberg's quantum mechanics, and Schroedinger's wave mechanics. We provide an extensive analysis of the lectures and discussions that took place, in the light of current debates about the meaning of quantum theory. The proceedings contain much unexpected material, including extensive discussions of de Broglie's pilot-wave theory (which de Broglie presented for a many-body system), and a "quantum mechanics" apparently lacking in wave function collapse or fundamental time evolution. We hope that the book will contribute to the ongoing revival of research in quantum foundations, as well as stimulate a reconsideration of the historical development of quantum physics. A more detailed description of the book may be found in the Preface. (Copyright by Cambridge University Press (ISBN: 9780521814218).)
Abstract This conference was lauded by Heisenberg as, “officially, the completion of the quantum theory,” while Langevin remarked it was, “where the confusion of ideas reached its peak.” The conference was held just as the theory had reached maturity, only two years after Heisenberg’s matrix mechanics was invented. De Broglie argued for his pilot wave theory, which was shot down by Pauli using an incorrect argument and in later years was re-introduced as the de Broglie–Bohm theory. Heisenberg and Dirac debated the meaning of superposition and the “collapse” of the wave function. Bohr and Einstein engaged in their legendary debate. In the conference proceedings, we see the main contributors to the new theory attempt to come to terms with its enigmas.
At the 1927 Solvay conference, three different theories of quantum mechanics were presented; however, the physicists present failed to reach a consensus. Today, many fundamental questions about quantum physics remain unanswered. One of the theories presented at the conference was Louis de Broglie's pilot-wave dynamics. This work was subsequently neglected in historical accounts; however, recent studies of de Broglie's original idea have rediscovered a powerful and original theory. In de Broglie's theory, quantum theory emerges as a special subset of a wider physics, which allows non-local signals and violation of the uncertainty principle. Experimental evidence for this new physics might be found in the cosmological-microwave-background anisotropies and with the detection of relic particles with exotic new properties predicted by the theory.
At the 1927 Solvay conference, three different theories of quantum mechanics were presented; however, the physicists present failed to reach a consensus. Today, many fundamental questions about quantum physics remain unanswered. One of the theories presented at the conference was Louis de Broglie's pilot-wave dynamics. This work was subsequently neglected in historical accounts; however, recent studies of de Broglie's original idea have rediscovered a powerful and original theory. In de Broglie's theory, quantum theory emerges as a special subset of a wider physics, which allows non-local signals and violation of the uncertainty principle. Experimental evidence for this new physics might be found in the cosmological-microwave-background anisotropies and with the detection of relic particles with exotic new properties predicted by the theory.
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.
Largely drawn from “Quantum Theory at the Crossroads : Reconsideringthe1927 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.