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Heinz von Foerster 100
Organizing Institutions:
Heinz von Foerster Gesellschaft / Wien
ASC – American Society for Cybernetics
WISDOM – Wiener Institut für
  sozialwissenschaftliche Dokumentation und Methodik

Institut für Zeitgeschichte | Universität Wien
AINS – Austrian Institute for Nonlinear Studies
Lee Smolin

A real ensemble interpretation of quantum mechanics

Perimeter Institute
Ontario, Canada

A new ensemble interpretation of quantum mechanics is proposed according to which the ensemble associated to a quantum state really exists: it is the ensemble of all the systems in the same quantum state in the universe. Individual systems within the ensemble have microscopic states, described by beables. The probabilities of quantum theory turn out to be just ordinary relative frequencies probabilities in these ensembles. Laws for the evolution of the beables of individual systems are given such that their ensemble relative frequencies evolve in a way that reproduces the predictions of quantum mechanics.

These laws are highly non-local and involve a new kind of interaction between the members of an ensemble that define a quantum state. These include a stochastic process by which individual systems copy the beables of other systems in the ensembles of which they are a member. The probabilities for these copy processes do not depend on where the systems are in space, but do depend on the distribution of beables in the ensemble.

Macroscopic systems then are distinguished by being large and complex enough that they have no copies in the universe. They then cannot evolve by the copy law, and hence do not evolve stochastically according to quantum dynamics. This implies novel departures from quantum mechanics for systems in quantum states that can be expected to have few copies in the universe. At the same time, we are able to argue that the centre of masses of large macroscopic systems do satisfy Newton's laws.


Brief Biography:

Lee Smolin was born in New York City in 1955 and raised there and in Cincinnati.
After leaving high school early, he attended Hampshire College and the University
of Cincinnati, graduating from Hampshire in 1975 with a degree in Physics and Philosophy.
He attended Harvard University for graduate school receiving a Ph.D. in theoretical physics
in 1979. He held postdoctoral positions at the Institute for Advanced Study in Princeton,
The Institute for Theoretical Physics (now KITP) in Santa Barbara and the Enrico Fermi
Institute at the University of Chicago. This was followed by faculty positions at Yale,
Syracuse and Penn State Universities, where he helped to found the Center for Gravitational
Physics and Geometry. He also held visiting positions at varioous times at Cambridge and
Oxford Universities and at SISSA and the Universities of Rome and Trento in Italy.
He was a Visiting Professor at Imperial College from 1999 to 2001. In September of 2001
he moved to Canada to be a founding member of the Perimeter Institute for Theoretical Physics,
where he has been ever since.

Lee's main contributions to research are so far to the field of quantum gravity. He was, with
Abhay Ashtekar and Carlo Rovelli, a founder of the approach known as loop quantum gravity, but
he has contributed to other approaches including string theory and causal dynamical triangulations.
He is also known for proposing the notion of the landscape of theories, based on his application
of Darwinian methods to Cosmology. He has contributed also to the foundations of quantum mechanics,
elementary particle phyiscs and theoretical biology. He also has a strong interest in philosophy
and his three books, Life of the Cosmos, Three Roads to Quantum Gravity and The Trouble with Physics
are in part philosophical explorations of issues raised by contemporary physics.