From No-signaling to Spontaneous Localization Theories

Valia Allori

Published Jan 1, 2019• 0 citations

Abstract

GianCarlo Ghirardi passed away on June 1st, 201. He would have turned 83 on October 28, 2018. He was without any doubt one of the most prominent theoretical physicists working on the foundation and the philosophy of quantum mechanics. In this paper I review some of his achievements and underline how his research influenced the philosophy of physics community.

Related papers

The Quantum Universe

Stephen L Adler, Angelo Bassi, Fay Dürr

This special issue of Journal of Physics A: Mathematical and Theoretical entitled 'The Quantum Universe' is dedicated to Professor Giancarlo Ghirardi on the occasion of his 70th birthday. Giancarlo Ghirardi has made many important contributions to the foundations of quantum mechanics including the celebrated Ghirardi–Rimini–Weber (GRW) model of spontaneous wavefunction collapse. However, although Professor Ghirardi's birthday is the inspiration for this issue, it has a much broader scope than the area traditionally known as Foundations of Quantum Mechanics. All invited authors are experts in areas of physics in which quantum theory is fundamental: non relativistic quantum mechanics, quantum computation and information, quantum field theory, quantum gravity, quantum cosmology and philosophy of science. The issue was conceived as an opportunity for workers in these diverse areas to share with the widest possible readership their views on quantum theory. Authors were encouraged to give their personal assessment of the role of quantum theory in their work particularly as it pertains to a vision of the global aims of their research. The articles are accessible to any physicist with a solid knowledge of quantum mechanics, and many contain an emphasis on conceptual developments, both those achieved and those hoped for. One theme that runs throughout Giancarlo Ghirardi's contributions to science is the unity of physics: the development of the GRW model itself was motivated by the conviction that the same physics should govern microscopic and macroscopic systems. However, readers of this special issue will clearly see that there is no unity as yet in the views of workers on fundamental quantum theories. Indeed the diversity of the articles, ranging from technical developments in well defined approaches, to new proposals for interpretations of quantum mechanics, indicates the state of fundamental physics: healthily active and yet lacking the consensus we seek in science. Much work clearly remains and this volume has the potential to be a lasting reference recording the achievements of, and crucial further challenges for, our quantum community.

Journal of Physics A Mathematical and TheoreticalMar 7, 20070 citations

GianCarlo Ghirardi and the interpretation of quantum physics

Bernard d’Espagnat

This paper comprises a few notes illustrating the impact of GianCarlo Ghirardi's achievements, even on the thinking of a 'non-realist'.

Journal of Physics A Mathematical and TheoreticalMar 7, 20072 citations

Why are we philosophers interested in quantum field theory?

Tian Yu Cao

This two-tier conference signals a new phase of philosophers' interest in quantum field theory, which has been growing noticeably in the last few years. However, some prominent physicists have shown their deep suspicions against ignorant philosophers' intrusion into their profession, and have expressed their hostility quite openly. In the philosophy community, some prominent philosophers of physics have also expressed their suspicions against the rationale of moving away from the profound foundational problems raised by Einstein and Bohr, Bohm and Bell, such as those concerning the nature of space-time and measurement, possibility and implications of hidden variables and nonlocality, and stepping into the technical complexity of quantum field theory, which is only an application of quantum mechanics in general without intrinsically distinct philosophical questions to be explored. In order to dispel these suspicions, it is desirable to highlight certain aspects of quantum field theory which require philosophical reflections and deserve further investigations. This discussion intends to suggest that philosophers can learn many important lessons from quantum field theory, and may be of some help in clarifying its conceptual foundations. At this stage of crisis that quantum field theory is experiencing now, the clarification may contribute to the radical transformation of our basic concepts in theoretical physics, which is necessary for a happy resolution of the crisis and the emergence of a new promising fundamental physical theory. Generally speaking, philosophers are interested in the metaphysical assumptions adopted by science and the world picture suggested by science.

Cambridge University Press eBooksFeb 18, 199916 citations

My life with GianCarlo Ghirardi, a great friend, a great teacher and a great physicist

de Stefano, Francesco

In these shorts notes I want to remembermy relationship with GianCarlo Ghirardi, who was my supervisor in my Master Degree in Physics at the University of Trieste and then he became a very deep and close friend. I don't want to describe in details his scientific steps in the world of modern Physics: many others will make better than me. I want only to share which was my relationship with him as a teacher, a man, and expecially as a deep friend, for more than 40 years.

arXiv:1808.01651Jun 6, 20180 citations

Collapse of the Wave Function

Dorje C. Brody, Lane P. Hughston

This is the first single volume about the collapse theories of quantum mechanics, which is becoming a very active field of research in both physics and philosophy. In standard quantum mechanics, it is postulated that when the wave function of a quantum system is measured, it no longer follows the Schrödinger equation, but instantaneously and randomly collapses to one of the wave functions that correspond to definite measurement results. However, why and how a definite measurement result appears is unknown. A promising solution to this problem are collapse theories in which the collapse of the wave function is spontaneous and dynamical. Chapters written by distinguished physicists and philosophers of physics discuss the origin and implications of wave-function collapse, the controversies around collapse models and their ontologies, and new arguments for the reality of wave function collapse. This is an invaluable resource for students and researchers interested in the philosophy of physics and foundations of quantum mechanics.

Cambridge University Press eBooksApr 20, 201812 citations

Philosophy of Physics: Quantum Theory

Tim Maudlin

In this book, Tim Maudlin, one of the worlds leading philosophers of physics, offers a sophisticated, original introduction to the philosophy of quantum mechanics. The briefest, clearest, and most refined account of his influential approach to the subject, the book will be invaluable to all students of philosophy and physics. Quantum mechanics holds a unique place in the history of physics. It has produced the most accurate predictions of any scientific theory, but, more astonishing, there has never been any agreement about what the theory implies about physical reality. Maudlin argues that the very term quantum theory is a misnomer. A proper physical theory should clearly describe what is there and what it doesyet standard textbooks present quantum mechanics as a predictive recipe in search of a physical theory. In contrast, Maudlin explores three proper theories that recover the quantum predictions: the indeterministic wavefunction collapse theory of Ghirardi, Rimini, and Weber; the deterministic particle theory of deBroglie and Bohm; and the conceptually challenging Many Worlds theory of Everett. Each offers a radically different proposal for the nature of physical reality, but Maudlin shows that none of them are what they are generally taken to be.

Mar 19, 201950 citations