ERC FUNDED PROJECTS

A major part of the physical and chemical processes occurring in the atmosphere involves the turbulent transport of tiny particles. Current studies and models use a formulation in terms of mean fields, where the strong variations in the dynamical and statistical properties of the particles are neglected and where the underlying fluctuations of the fluid flow velocity are oversimplified. Devising an accurate understanding of the influence of air turbulence and of the extreme fluctuations that it generates in the dispersed phase remains a challenging issue. This project aims at coordinating and integrating theoretical, numerical, experimental, and observational efforts to develop a new statistical understanding of the role of fluctuations in atmospheric transport processes. The proposed work will cover individual as well as collective behaviors and will provide a systematic and unified description of targeted specific processes involving suspended drops or particles: the dispersion of pollutants from a source, the growth by condensation and coagulation of droplets and ice crystals in clouds, the scavenging, settling and re-suspension of aerosols, and the radiative and climatic effects of particles. The proposed approach is based on the use of tools borrowed from statistical physics and field theory, and from the theory of large deviations and of random dynamical systems in order to design new observables that will be simultaneously tractable analytically in simplified models and of relevance for the quantitative handling of such physical mechanisms. One of the outcomes will be to provide a new framework for improving and refining the methods used in meteorology and atmospheric sciences and to answer the long-standing question of the effects of suspended particles onto climate.

1 200 000 €

Start date: 2009-11-01, End date: 2014-10-31

A contact structure on an odd dimensional manifold in a maximally non integrable hyperplane field. It is the odd dimensional counterpart of a symplectic structure. Contact and symplectic topology is a recent and very active area that studies intrinsic questions about existence, (non) uniqueness and rigidity of contact and symplectic structures. It is intimately related to many other important disciplines, such as dynamical systems, singularity theory, knot theory, Morse theory, complex analysis, ... Legendrian submanifolds are a distinguished class of submanifolds in a contact manifold, which are tangent to the contact distribution. These manifolds are of a particular interest in contact topology. Important classes of Legendrian submanifolds can be described using generating families, and this description can be used to define Legendrian invariants via Morse theory. Other the other hand, Legendrian contact homology is an invariant for Legendrian submanifolds, based on holomorphic curves. The goal of this research proposal is to study the relationship between these two approaches. More precisely, we plan to show that the generating family homology and the linearized Legendrian contact homology can be defined for the same class of Legendrian submanifolds, and are isomorphic. This correspondence should be established using a parametrized version of symplectic homology, being developed by the Principal Investigator in collaboration with Oancea. Such a result would give an entirely new type of information about holomorphic curves invariants. Moreover, it can be used to obtain more general structural results on linearized Legendrian contact homology, to extend recent results on existence of Reeb chords, and to gain a much better understanding of the geography of Legendrian submanifolds.

710 000 €

Start date: 2009-11-01, End date: 2014-10-31

The main objective of this proposal is to design and implement a novel scheme for efficient, deterministic, lossless photon-photon interactions, and to exploit it to achieve logical processing and quantum measurements on optical light beams. For that purpose, we will create, study and exploit a new transparent medium, based on the transient excitation of Rydberg polaritons, where the optical non-linearities are so large that they can act at the single photon level. These techniques will be applied to perform quantum measurements and manipulations of light beams. This will include the deterministic generation of single photons and optical Schrödinger's cat states, the implementation of quantum non-demolition (QND) measurements for the photon number and the parity operators, and the demonstration of controlled-phase and controlled-not quantum gates. These operations will be implemented in the optical domain, where they can be combined with efficient propagation in free space or in optical fibers, and with high efficiency detectors already available, in order to open an avenue towards a fully deterministic quantum engineering of light.

2 496 000 €

Start date: 2010-01-01, End date: 2014-12-31

In spite of considerable work in artificial intelligence, machine learning, and pattern recognition in the past 50 years, we have no machine capable of adapting to the physical and social environment with the flexibility, robustness and versatility of a 6-months old human child. Instead of trying to simulate directly the adult s intelligence, EXPLORERS proposes to focus on the developmental principles that give rise to intelligence in infants by re-implementing them in machines. Framed in the developmental/epigenetic robotics research agenda, and grounded in research in developmental psychology, its main target is to build robotic machines capable of autonomously learning and re-using a variety of skills and know-how that were not specified at design time, and with initially limited knowledge of the body and of the environment in which it will operate. This implies several fundamental issues: How can a robot discover its body and its relationships with the physical and social environment? How can it learn new skills without the intervention of an engineer? What internal motivations shall guide its exploration of vast spaces of skills? Can it learn through natural social interactions with humans? How to represent the learnt skills and how can they be re-used? EXPLORERS attacks directly those questions by proposing a series of fundamental scientific and technological advances, including computational intrinsic motivation systems for learning basic sensorimotor skills reused for grounded acquisition of the meaning of new words. This project not only addresses fundamental scientific questions, but also relates to important societal issues: personal home robots are bound to become part of everyday life in the 21st century, in particular as helpful social companions in an aging society. EXPLORERS objectives converge to the challenges implied by this vision: robots will have to be able to adapt and learn new skills in the unknown homes of users who are not engineers.

1 572 215 €

Start date: 2009-12-01, End date: 2015-05-31