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Quantum fluctuations or "noise" are ubiquitous. Though treated as random in statistical approaches, fluctuations
often arise from dynamical correlations between the underlying degrees of freedom of the physical system. In some
situations noise complicates obtaining the information of interest from an experiment or a numerical simulation. In
others, the physics one is interested in is contained in the noise itself (in the words of Rolf Landauer "the noise is the
signal" [1]). In either case understanding and characterization the properties of the noise is crucial.
Although in systems with large numbers of particles fluctuations of macroscopic physical quantities usually obey a
gaussian distribution, in many circumstances interesting physical phenomena correspond to atypical, rare fluctuations
that do not follow a normal distribution.
Non-gaussian fluctuations occur as mesoscopic (sample to sample) static fluctuations caused by quenched randomness
and temporal fluctuations of physical observables in a given system. Both static and dynamic fluctuations are
accessible in experiments with mesoscopic solids, trapped cold atoms, and ensembles of photons in quantum optics
settings. Remarkably, problems raised in the interpretation of such experiments are very similar to the problems in
assessing the results of Monte Carlo simulations of quantum many-body systems, especially of simulations in nuclear
and particle physics. There has been much recent and ongoing work in all of these fields. Despite the common issue
- strong quantum fluctuations, researchers working in these areas customarily use different tools. The purpose of the
program was to bring the practitioners of these areas together, facilitate exchange of expertise and scientific ideas
between the rather disparate communities of condensed matter and nuclear physicists, and explore to what extent
non-gaussian statistics observed in physical systems and their theoretical treatment share universal properties and
common features.
The workshop was attended by over thirty participants. The program was subdivided into several overlapping
periods according to the following themes: noise in quantum Monte Carlo simulations and the fermion sign problem,
quantum fluctuations in cold atomic gases, and noise and quantum coherence effects in electron condensed matter
systems. Most of the talks combined an introductory overview for non-experts with presentations of recent results and
summary of outstanding problems. The format of the workshop provided ample time for discussions, both scheduled
and spontaneous. This format worked very well. It helped to initiate many fruitful contacts between the participants,
generate ideas for future research projects, and ferment new collaborations.
[1] R. Landauer, "Condensed-matter physics: The noise is the signal", Nature 392, 658( 1998).
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