Beyond the Quantum

A centenary after Einstein’s annus mirabilis it is timely to reconsider the foundations
of physical theories. Quantum mechanics, our best theory, works wherever it has
been applied, in fields ranging from the solid state and quantum chemistry to high
energy physics and the early Universe. Its most modern application is Quantum
String Theory.
Despite all the success, there remains the old question: what is this theory actually stands for? On the foundational level, it has come hardly much further than
the Feynman quote “nobody understands quantum mechanics”. Up to this date,
quantum effects such as uncertainty, interference and entanglement have become
experimental facts, but their explanation remains puzzling. It was Einstein’s dream
that one day quantum theory would appear to arise from physics at a deeper level,
more precisely, as the statistics of such a world.
Indeed, none of the present theories is capable to describe, even in principle, individual measurements or individual events. Though it was long agreed that “such
questions should not be posed” their relevance is getting more and more acknowledged. In its July 2005 issue, the journal Science selects among the Top 25 questions
that face scientific inquiry over the next quarter-century: Do Deeper Principles Underlie Quantum Uncertainty and Nonlocality?, together with the probably related
questions What is the Universe Made of ? and Can the Laws of Physics be Unified?
During the last couple of years various new results have been reported supporting the possibility of an underlying more deterministic structure: Various arguments in favor of the statistical interpretation of quantum mechanics, deriving rather
than postulating the von Neumann collapse and the Born rule, loopholes in nonlocality arguments, quantum gravity approaches, demonstration of the compatibility
of quantum theory and contextual Kolmogorov probability theory, Bohmian mechanics, stochastic electrodynamics, collapse models, the Empiricist interpretation
of quantum mechanics, occurrence of entanglement in classical physics. Stochastic
optics has proposed a local and realistic explanation of entanglement for experiments with photons. Intriguing ideas have been published comparing over-extremal
Kerr-Newman solutions in electrogravity with charged, spinning elementary particles, which invites to consider topological features of these solutions.
Some of these questions may lead to tests in quantum optics, where entangled
Bell-pairs are routinely made.
July 23, 2007 12:0 WSPC – Proceedings Trim Size: 9.75in x 6.5in master
A workshop that would put together and compare these many different approaches was deemed very timely. Progress can be hoped for by combining the
insights from the communities of the quantum gravity and statistical/empirical interpretations of quantum mechanics with the communities from Stochastic Electrodynamics, Stochastic Optics, Stochastic Collapse and Bohm, to focus on questions
such as: Problems and paradoxes in ordinary quantum mechanics and quantum field
theory, including quantum state reduction in relativistic quantum theory; Is there
experimental evidence to go beyond the ordinary quantum theory? What have we
learned from quantum gravity and string theory for these problems? Such questions
were confronted to experimental, mathematical and philosophical insights, and these
proceedings are a written testimony of this confrontation.
In the opening address of the workshop it was stressed that individual measurements give individual outcomes. The statistics of the outcomes of measurements
is described by quantum theory. But since it is the task of theoretical physicists
to describe Nature, they have to find a theoretical description for the underlying
individual events.
To open the proceedings, we may recall the last opening words of the workshop