Roland Omnès (18 February 1931 – 2 August 2022) was a French physicist and author of several books that aimed to give non-scientists the information required to understand
quantum mechanics
Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...
.
Biography
Omnès was Professor Emeritus of Theoretical Physics in the Faculté des Sciences at
Orsay
Orsay () is a Communes of France, commune in the Essonne Departments of France, department in Île-de-France in northern France. It is located in the southwestern suburbs of Paris, France, from the Kilometre Zero, centre of Paris.
A fortifie ...
, at the
Université Paris-Sud
Paris-Sud University (), also known as the University of Paris — XI (or as the Orsay Faculty of Sciences, University of Paris before 1971), was a French research university distributed among several campuses in the southern suburbs of Paris, ...
quantum decoherence
Quantum decoherence is the loss of quantum coherence. It involves generally a loss of information of a system to its environment. Quantum decoherence has been studied to understand how quantum systems convert to systems that can be expla ...
approaches in quantum mechanics. He received the Paul-Langevin Prize in 1959.
Omnès died in
Saint-Rémy-lès-Chevreuse
Saint-Rémy-lès-Chevreuse (, ) is a commune in the Yvelines department, in the Île-de-France region of north-central France.
Saint-Rémy-lès-Chevreuse station is the southwestern endpoint of the RER B line from Paris.Quantum Philosophy''), Omnès argues that:
# "Until modern times, intuitive, rational thought was sufficient to describe the world; mathematics remained an adjunct, simply helping to make our intuitive descriptions more precise."
# "In the late 19th and early 20th centuries, we arrived at a Fracture between common sense and our best descriptions of reality. Our formal description became the truest picture (most
consistent
In deductive logic, a consistent theory is one that does not lead to a logical contradiction. A theory T is consistent if there is no formula \varphi such that both \varphi and its negation \lnot\varphi are elements of the set of consequences ...
with how things are, experimentally) and common sense was left behind. Our best descriptions of reality are now incomprehensible to common sense alone, and our intuitions about how things are often negated by experiment and theory."
# "However it is, finally, possible to recover common sense from our formal, mathematical description of reality. We can now demonstrate that the laws of classical logic, classical probability, and classical dynamics (of common sense, in fact) apply at the macroscopic level, even in a world described by a single, unitary wavefunction. This follows from the fundamental principles of quantum mechanics, with no need for extra logical constructs such as wave function collapse."
"We will never", Omnès believed, "find a common sense interpretation of quantum law itself. Nevertheless, it is now possible to see that common sense and quantum reality are compatible with each other: we can enter the world at either starting point, and we will find that each leads to the other: experiment leads to theory, and the theory can now recover the common sense framework in which the experiment was conducted (and in which our lives are lived)."
The new 'Copenhagen Interpretation'?
Omnès's work is sometimes described as an update to the
Copenhagen interpretation
The Copenhagen interpretation is a collection of views about the meaning of quantum mechanics, stemming from the work of Niels Bohr, Werner Heisenberg, Max Born, and others. While "Copenhagen" refers to the Danish city, the use as an "interpretat ...
of quantum mechanics. This is somewhat misleading. The relationship between the two accounts is as follows:
The Copenhagen interpretation of quantum mechanics (argued for most centrally by
Niels Bohr
Niels Henrik David Bohr (, ; ; 7 October 1885 – 18 November 1962) was a Danish theoretical physicist who made foundational contributions to understanding atomic structure and old quantum theory, quantum theory, for which he received the No ...
) advises that physicists "shut up and calculate". It holds that some questions are unanswerable, and that there are inexplicable rules that reconcile the quantum description of reality (which is experimentally correct to at least 10 decimal places of accuracy) with human-observed reality (which seems self-evidently correct, and yet is apparently in contradiction with quantum law).
Omnès claimed that there is a self-consistent framework that enables recovering the principles of classical common sense—and knowing, precisely, their limits—starting from fundamental quantum law.
Bibliography
The work Omnès presents in his books was developed by Omnès himself,
Robert B. Griffiths
Robert B. Griffiths (February 25, 1937) is an American physicist at Carnegie Mellon University. He is the originator of the consistent histories approach to quantum mechanics, which has since been developed by himself, Roland Omnès, Murray Gel ...
,
Murray Gell-Mann
Murray Gell-Mann (; September 15, 1929 – May 24, 2019) was an American theoretical physicist who played a preeminent role in the development of the theory of elementary particles. Gell-Mann introduced the concept of quarks as the funda ...
,
James Hartle
James Burkett Hartle (August 17, 1939 – May 17, 2023) was an American theoretical physicist. He joined the faculty of the University of California, Santa Barbara in 1966, and was a member of the external faculty of the Santa Fe Institute. Hart ...
, and others.
* ''The Interpretation of Quantum Mechanics'' (Princeton University Press, 1994) – a technical exposition of Omnès's account, for physicists.
* ''Understanding Quantum Mechanics'' (Princeton University Press, 1999) – a somewhat less technical revision and updating of the above work, also intended for physicists.
* '' Quantum Philosophy: Understanding and Interpreting Contemporary Science'' (English Edition – Princeton University Press, 1999); (French Edition - Gallimard, 1994)
* ''Converging Realities: Toward a Common Philosophy of Physics and Mathematics'' (Princeton University Press, 2004) – Here Omnès presents, in detail, his position on the relationship between mathematics and reality which he started to develop in '' Quantum Philosophy''.A Physicist's Philosophy of Mathematics By Reuben Hersh (book review)