Project acronym 2-3-AUT
Project Surfaces, 3-manifolds and automorphism groups
Researcher (PI) Nathalie Wahl
Host Institution (HI) KOBENHAVNS UNIVERSITET
Call Details Starting Grant (StG), PE1, ERC-2009-StG
Summary The scientific goal of the proposal is to answer central questions related to diffeomorphism groups of manifolds of dimension 2 and 3, and to their deformation invariant analogs, the mapping class groups. While the classification of surfaces has been known for more than a century, their automorphism groups have yet to be fully understood. Even less is known about diffeomorphisms of 3-manifolds despite much interest, and the objects here have only been classified recently, by the breakthrough work of Perelman on the Poincar\'e and geometrization conjectures. In dimension 2, I will focus on the relationship between mapping class groups and topological conformal field theories, with applications to Hochschild homology. In dimension 3, I propose to compute the stable homology of classifying spaces of diffeomorphism groups and mapping class groups, as well as study the homotopy type of the space of diffeomorphisms. I propose moreover to establish homological stability theorems in the wider context of automorphism groups and more general families of groups. The project combines breakthrough methods from homotopy theory with methods from differential and geometric topology. The research team will consist of 3 PhD students, and 4 postdocs, which I will lead.
Summary
The scientific goal of the proposal is to answer central questions related to diffeomorphism groups of manifolds of dimension 2 and 3, and to their deformation invariant analogs, the mapping class groups. While the classification of surfaces has been known for more than a century, their automorphism groups have yet to be fully understood. Even less is known about diffeomorphisms of 3-manifolds despite much interest, and the objects here have only been classified recently, by the breakthrough work of Perelman on the Poincar\'e and geometrization conjectures. In dimension 2, I will focus on the relationship between mapping class groups and topological conformal field theories, with applications to Hochschild homology. In dimension 3, I propose to compute the stable homology of classifying spaces of diffeomorphism groups and mapping class groups, as well as study the homotopy type of the space of diffeomorphisms. I propose moreover to establish homological stability theorems in the wider context of automorphism groups and more general families of groups. The project combines breakthrough methods from homotopy theory with methods from differential and geometric topology. The research team will consist of 3 PhD students, and 4 postdocs, which I will lead.
Max ERC Funding
724 992 €
Duration
Start date: 2009-11-01, End date: 2014-10-31
Project acronym 2F4BIODYN
Project Two-Field Nuclear Magnetic Resonance Spectroscopy for the Exploration of Biomolecular Dynamics
Researcher (PI) Fabien Ferrage
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2011-StG_20101014
Summary The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Summary
The paradigm of the structure-function relationship in proteins is outdated. Biological macromolecules and supramolecular assemblies are highly dynamic objects. Evidence that their motions are of utmost importance to their functions is regularly identified. The understanding of the physical chemistry of biological processes at an atomic level has to rely not only on the description of structure but also on the characterization of molecular motions.
The investigation of protein motions will be undertaken with a very innovative methodological approach in nuclear magnetic resonance relaxation. In order to widen the ranges of frequencies at which local motions in proteins are probed, we will first use and develop new techniques for a prototype shuttle system for the measurement of relaxation at low fields on a high-field NMR spectrometer. Second, we will develop a novel system: a set of low-field NMR spectrometers designed as accessories for high-field spectrometers. Used in conjunction with the shuttle, this system will offer (i) the sensitivity and resolution (i.e. atomic level information) of a high-field spectrometer (ii) the access to low fields of a relaxometer and (iii) the ability to measure a wide variety of relaxation rates with high accuracy. This system will benefit from the latest technology in homogeneous permanent magnet development to allow a control of spin systems identical to that of a high-resolution probe. This new apparatus will open the way to the use of NMR relaxation at low fields for the refinement of protein motions at an atomic scale.
Applications of this novel approach will focus on the bright side of protein dynamics: (i) the largely unexplored dynamics of intrinsically disordered proteins, and (ii) domain motions in large proteins. In both cases, we will investigate a series of diverse protein systems with implications in development, cancer and immunity.
Max ERC Funding
1 462 080 €
Duration
Start date: 2012-01-01, End date: 2017-12-31
Project acronym A-LIFE
Project The asymmetry of life: towards a unified view of the emergence of biological homochirality
Researcher (PI) Cornelia MEINERT
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2018-STG
Summary What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Summary
What is responsible for the emergence of homochirality, the almost exclusive use of one enantiomer over its mirror image? And what led to the evolution of life’s homochiral biopolymers, DNA/RNA, proteins and lipids, where all the constituent monomers exhibit the same handedness?
Based on in-situ observations and laboratory studies, we propose that this handedness occurs when chiral biomolecules are synthesized asymmetrically through interaction with circularly polarized photons in interstellar space. The ultimate goal of this project will be to demonstrate how the diverse set of heterogeneous enantioenriched molecules, available from meteoritic impact, assembles into homochiral pre-biopolymers, by simulating the evolutionary stages on early Earth. My recent research has shown that the central chiral unit of RNA, ribose, forms readily under simulated comet conditions and this has provided valuable new insights into the accessibility of precursors of genetic material in interstellar environments. The significance of this project arises due to the current lack of experimental demonstration that amino acids, sugars and lipids can simultaneously and asymmetrically be synthesized by a universal physical selection process.
A synergistic methodology will be developed to build a unified theory for the origin of all chiral biological building blocks and their assembly into homochiral supramolecular entities. For the first time, advanced analyses of astrophysical-relevant samples, asymmetric photochemistry triggered by circularly polarized synchrotron and laser sources, and chiral amplification due to polymerization processes will be combined. Intermediates and autocatalytic reaction kinetics will be monitored and supported by quantum calculations to understand the underlying processes. A unified theory on the asymmetric formation and self-assembly of life’s biopolymers is groundbreaking and will impact the whole conceptual foundation of the origin of life.
Max ERC Funding
1 500 000 €
Duration
Start date: 2019-04-01, End date: 2024-03-31
Project acronym A2C2
Project Atmospheric flow Analogues and Climate Change
Researcher (PI) Pascal Yiou
Host Institution (HI) COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
Call Details Advanced Grant (AdG), PE10, ERC-2013-ADG
Summary "The A2C2 project treats two major challenges in climate and atmospheric research: the time dependence of the climate attractor to external forcings (solar, volcanic eruptions and anthropogenic), and the attribution of extreme climate events occurring in the northern extra-tropics. The main difficulties are the limited climate information, the computer cost of model simulations, and mathematical assumptions that are hardly verified and often overlooked in the literature.
A2C2 proposes a practical framework to overcome those three difficulties, linking the theory of dynamical systems and statistics. We will generalize the methodology of flow analogues to multiple databases in order to obtain probabilistic descriptions of analogue decompositions.
The project is divided into three workpackages (WP). WP1 embeds the analogue method in the theory of dynamical systems in order to provide a metric of an attractor deformation in time. The important methodological step is to detect trends or persisting outliers in the dates and scores of analogues when the system yields time-varying forcings. This is done from idealized models and full size climate models in which the forcings (anthropogenic and natural) are known.
A2C2 creates an open source toolkit to compute flow analogues from a wide array of databases (WP2). WP3 treats the two scientific challenges with the analogue method and multiple model ensembles, hence allowing uncertainty estimates under realistic mathematical hypotheses. The flow analogue methodology allows a systematic and quasi real-time analysis of extreme events, which is currently out of the reach of conventional climate modeling approaches.
The major breakthrough of A2C2 is to bridge the gap between operational needs (the immediate analysis of climate events) and the understanding long-term climate changes. A2C2 opens new research horizons for the exploitation of ensembles of simulations and reliable estimates of uncertainty."
Summary
"The A2C2 project treats two major challenges in climate and atmospheric research: the time dependence of the climate attractor to external forcings (solar, volcanic eruptions and anthropogenic), and the attribution of extreme climate events occurring in the northern extra-tropics. The main difficulties are the limited climate information, the computer cost of model simulations, and mathematical assumptions that are hardly verified and often overlooked in the literature.
A2C2 proposes a practical framework to overcome those three difficulties, linking the theory of dynamical systems and statistics. We will generalize the methodology of flow analogues to multiple databases in order to obtain probabilistic descriptions of analogue decompositions.
The project is divided into three workpackages (WP). WP1 embeds the analogue method in the theory of dynamical systems in order to provide a metric of an attractor deformation in time. The important methodological step is to detect trends or persisting outliers in the dates and scores of analogues when the system yields time-varying forcings. This is done from idealized models and full size climate models in which the forcings (anthropogenic and natural) are known.
A2C2 creates an open source toolkit to compute flow analogues from a wide array of databases (WP2). WP3 treats the two scientific challenges with the analogue method and multiple model ensembles, hence allowing uncertainty estimates under realistic mathematical hypotheses. The flow analogue methodology allows a systematic and quasi real-time analysis of extreme events, which is currently out of the reach of conventional climate modeling approaches.
The major breakthrough of A2C2 is to bridge the gap between operational needs (the immediate analysis of climate events) and the understanding long-term climate changes. A2C2 opens new research horizons for the exploitation of ensembles of simulations and reliable estimates of uncertainty."
Max ERC Funding
1 491 457 €
Duration
Start date: 2014-03-01, End date: 2019-02-28
Project acronym AAMOT
Project Arithmetic of automorphic motives
Researcher (PI) Michael Harris
Host Institution (HI) INSTITUT DES HAUTES ETUDES SCIENTIFIQUES
Call Details Advanced Grant (AdG), PE1, ERC-2011-ADG_20110209
Summary The primary purpose of this project is to build on recent spectacular progress in the Langlands program to study the arithmetic properties of automorphic motives constructed in the cohomology of Shimura varieties. Because automorphic methods are available to study the L-functions of these motives, which include elliptic curves and certain families of Calabi-Yau varieties over totally real fields (possibly after base change), they represent the most accessible class of varieties for which one can hope to verify fundamental conjectures on special values of L-functions, including Deligne's conjecture and the Main Conjecture of Iwasawa theory. Immediate goals include the proof of irreducibility of automorphic Galois representations; the establishment of period relations for automorphic and potentially automorphic realizations of motives in the cohomology of distinct Shimura varieties; the construction of p-adic L-functions for these and related motives, notably adjoint and tensor product L-functions in p-adic families; and the geometrization of the p-adic and mod p Langlands program. All four goals, as well as the others mentioned in the body of the proposal, are interconnected; the final goal provides a bridge to related work in geometric representation theory, algebraic geometry, and mathematical physics.
Summary
The primary purpose of this project is to build on recent spectacular progress in the Langlands program to study the arithmetic properties of automorphic motives constructed in the cohomology of Shimura varieties. Because automorphic methods are available to study the L-functions of these motives, which include elliptic curves and certain families of Calabi-Yau varieties over totally real fields (possibly after base change), they represent the most accessible class of varieties for which one can hope to verify fundamental conjectures on special values of L-functions, including Deligne's conjecture and the Main Conjecture of Iwasawa theory. Immediate goals include the proof of irreducibility of automorphic Galois representations; the establishment of period relations for automorphic and potentially automorphic realizations of motives in the cohomology of distinct Shimura varieties; the construction of p-adic L-functions for these and related motives, notably adjoint and tensor product L-functions in p-adic families; and the geometrization of the p-adic and mod p Langlands program. All four goals, as well as the others mentioned in the body of the proposal, are interconnected; the final goal provides a bridge to related work in geometric representation theory, algebraic geometry, and mathematical physics.
Max ERC Funding
1 491 348 €
Duration
Start date: 2012-06-01, End date: 2018-05-31
Project acronym ABIOS
Project ABIOtic Synthesis of RNA: an investigation on how life started before biology existed
Researcher (PI) Guillaume STIRNEMANN
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Starting Grant (StG), PE4, ERC-2017-STG
Summary The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Summary
The emergence of life is one of the most fascinating and yet largely unsolved questions in the natural sciences, and thus a significant challenge for scientists from many disciplines. There is growing evidence that ribonucleic acid (RNA) polymers, which are capable of genetic information storage and self-catalysis, were involved in the early forms of life. But despite recent progress, RNA synthesis without biological machineries is very challenging. The current project aims at understanding how to synthesize RNA in abiotic conditions. I will solve problems associated with three critical aspects of RNA formation that I will rationalize at a molecular level: (i) accumulation of precursors, (ii) formation of a chemical bond between RNA monomers, and (iii) tolerance for alternative backbone sugars or linkages. Because I will study problems ranging from the formation of chemical bonds up to the stability of large biopolymers, I propose an original computational multi-scale approach combining techniques that range from quantum calculations to large-scale all-atom simulations, employed together with efficient enhanced-sampling algorithms, forcefield improvement, cutting-edge analysis methods and model development.
My objectives are the following:
1 • To explain why the poorly-understood thermally-driven process of thermophoresis can contribute to the accumulation of dilute precursors.
2 • To understand why linking RNA monomers with phosphoester bonds is so difficult, to understand the molecular mechanism of possible catalysts and to suggest key improvements.
3 • To rationalize the molecular basis for RNA tolerance for alternative backbone sugars or linkages that have probably been incorporated in abiotic conditions.
This unique in-silico laboratory setup should significantly impact our comprehension of life’s origin by overcoming major obstacles to RNA abiotic formation, and in addition will reveal significant orthogonal outcomes for (bio)technological applications.
Max ERC Funding
1 497 031 €
Duration
Start date: 2018-02-01, End date: 2023-01-31
Project acronym ACAP
Project Acency Costs and Asset Pricing
Researcher (PI) Thomas Mariotti
Host Institution (HI) FONDATION JEAN-JACQUES LAFFONT,TOULOUSE SCIENCES ECONOMIQUES
Call Details Starting Grant (StG), SH1, ERC-2007-StG
Summary The main objective of this research project is to contribute at bridging the gap between the two main branches of financial theory, namely corporate finance and asset pricing. It is motivated by the conviction that these two aspects of financial activity should and can be analyzed within a unified framework. This research will borrow from these two approaches in order to construct theoretical models that allow one to analyze the design and issuance of financial securities, as well as the dynamics of their valuations. Unlike asset pricing, which takes as given the price of the fundamentals, the goal is to derive security price processes from a precise description of firm’s operations and internal frictions. Regarding the latter, and in line with traditional corporate finance theory, the analysis will emphasize the role of agency costs within the firm for the design of its securities. But the analysis will be pushed one step further by studying the impact of these agency costs on key financial variables such as stock and bond prices, leverage, book-to-market ratios, default risk, or the holding of liquidities by firms. One of the contributions of this research project is to show how these variables are interrelated when firms and investors agree upon optimal financial arrangements. The final objective is to derive a rich set of testable asset pricing implications that would eventually be brought to the data.
Summary
The main objective of this research project is to contribute at bridging the gap between the two main branches of financial theory, namely corporate finance and asset pricing. It is motivated by the conviction that these two aspects of financial activity should and can be analyzed within a unified framework. This research will borrow from these two approaches in order to construct theoretical models that allow one to analyze the design and issuance of financial securities, as well as the dynamics of their valuations. Unlike asset pricing, which takes as given the price of the fundamentals, the goal is to derive security price processes from a precise description of firm’s operations and internal frictions. Regarding the latter, and in line with traditional corporate finance theory, the analysis will emphasize the role of agency costs within the firm for the design of its securities. But the analysis will be pushed one step further by studying the impact of these agency costs on key financial variables such as stock and bond prices, leverage, book-to-market ratios, default risk, or the holding of liquidities by firms. One of the contributions of this research project is to show how these variables are interrelated when firms and investors agree upon optimal financial arrangements. The final objective is to derive a rich set of testable asset pricing implications that would eventually be brought to the data.
Max ERC Funding
1 000 000 €
Duration
Start date: 2008-11-01, End date: 2014-10-31
Project acronym ACCLIMATE
Project Elucidating the Causes and Effects of Atlantic Circulation Changes through Model-Data Integration
Researcher (PI) Claire Waelbroeck
Host Institution (HI) CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE CNRS
Call Details Advanced Grant (AdG), PE10, ERC-2013-ADG
Summary Rapid changes in ocean circulation and climate have been observed in marine sediment and ice cores, notably over the last 60 thousand years (ky), highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing.
To date, these rapid changes in climate and ocean circulation are still not fully explained. Two main obstacles prevent going beyond the current state of knowledge:
- Paleoclimatic proxy data are by essence only indirect indicators of the climatic variables, and thus can not be directly compared with model outputs;
- A 4-D (latitude, longitude, water depth, time) reconstruction of Atlantic water masses over the past 40 ky is lacking: previous studies have generated isolated records with disparate timescales which do not allow the causes of circulation changes to be identified.
Overcoming these two major limitations will lead to major breakthroughs in climate research. Concretely, I will create the first database of Atlantic deep-sea records over the last 40 ky, and extract full climatic information from these records through an innovative model-data integration scheme using an isotopic proxy forward modeling approach. The novelty and exceptional potential of this scheme is twofold: (i) it avoids hypotheses on proxy interpretation and hence suppresses or strongly reduces the errors of interpretation of paleoclimatic records; (ii) it produces states of the climate system that best explain the observations over the last 40 ky, while being consistent with the model physics.
Expected results include:
• The elucidation of the mechanisms explaining rapid changes in ocean circulation and climate over the last 40 ky,
• Improved climate model physics and parameterizations,
• The first projections of future climate changes obtained with a model able to reproduce the highly non linear behavior of the climate system observed over the last 40 ky.
Summary
Rapid changes in ocean circulation and climate have been observed in marine sediment and ice cores, notably over the last 60 thousand years (ky), highlighting the non-linear character of the climate system and underlining the possibility of rapid climate shifts in response to anthropogenic greenhouse gas forcing.
To date, these rapid changes in climate and ocean circulation are still not fully explained. Two main obstacles prevent going beyond the current state of knowledge:
- Paleoclimatic proxy data are by essence only indirect indicators of the climatic variables, and thus can not be directly compared with model outputs;
- A 4-D (latitude, longitude, water depth, time) reconstruction of Atlantic water masses over the past 40 ky is lacking: previous studies have generated isolated records with disparate timescales which do not allow the causes of circulation changes to be identified.
Overcoming these two major limitations will lead to major breakthroughs in climate research. Concretely, I will create the first database of Atlantic deep-sea records over the last 40 ky, and extract full climatic information from these records through an innovative model-data integration scheme using an isotopic proxy forward modeling approach. The novelty and exceptional potential of this scheme is twofold: (i) it avoids hypotheses on proxy interpretation and hence suppresses or strongly reduces the errors of interpretation of paleoclimatic records; (ii) it produces states of the climate system that best explain the observations over the last 40 ky, while being consistent with the model physics.
Expected results include:
• The elucidation of the mechanisms explaining rapid changes in ocean circulation and climate over the last 40 ky,
• Improved climate model physics and parameterizations,
• The first projections of future climate changes obtained with a model able to reproduce the highly non linear behavior of the climate system observed over the last 40 ky.
Max ERC Funding
3 000 000 €
Duration
Start date: 2014-02-01, End date: 2019-01-31
Project acronym ADAM
Project The Adaptive Auditory Mind
Researcher (PI) Shihab Shamma
Host Institution (HI) ECOLE NORMALE SUPERIEURE
Call Details Advanced Grant (AdG), SH4, ERC-2011-ADG_20110406
Summary Listening in realistic situations is an active process that engages perceptual and cognitive faculties, endowing speech with meaning, music with joy, and environmental sounds with emotion. Through hearing, humans and other animals navigate complex acoustic scenes, separate sound mixtures, and assess their behavioral relevance. These remarkable feats are currently beyond our understanding and exceed the capabilities of the most sophisticated audio engineering systems. The goal of the proposed research is to investigate experimentally a novel view of hearing, where active hearing emerges from a deep interplay between adaptive sensory processes and goal-directed cognition. Specifically, we shall explore the postulate that versatile perception is mediated by rapid-plasticity at the neuronal level. At the conjunction of sensory and cognitive processing, rapid-plasticity pervades all levels of auditory system, from the cochlea up to the auditory and prefrontal cortices. Exploiting fundamental statistical regularities of acoustics, it is what allows humans and other animal to deal so successfully with natural acoustic scenes where artificial systems fail. The project builds on the internationally recognized leadership of the PI in the fields of physiology and computational modeling, combined with the expertise of the Co-Investigator in psychophysics. Building on these highly complementary fields and several technical innovations, we hope to promote a novel view of auditory perception and cognition. We aim also to contribute significantly to translational research in the domain of signal processing for clinical hearing aids, given that many current limitations are not technological but rather conceptual. The project will finally result in the creation of laboratory facilities and an intellectual network unique in France and rare in all of Europe, combining cognitive, neural, and computational approaches to auditory neuroscience.
Summary
Listening in realistic situations is an active process that engages perceptual and cognitive faculties, endowing speech with meaning, music with joy, and environmental sounds with emotion. Through hearing, humans and other animals navigate complex acoustic scenes, separate sound mixtures, and assess their behavioral relevance. These remarkable feats are currently beyond our understanding and exceed the capabilities of the most sophisticated audio engineering systems. The goal of the proposed research is to investigate experimentally a novel view of hearing, where active hearing emerges from a deep interplay between adaptive sensory processes and goal-directed cognition. Specifically, we shall explore the postulate that versatile perception is mediated by rapid-plasticity at the neuronal level. At the conjunction of sensory and cognitive processing, rapid-plasticity pervades all levels of auditory system, from the cochlea up to the auditory and prefrontal cortices. Exploiting fundamental statistical regularities of acoustics, it is what allows humans and other animal to deal so successfully with natural acoustic scenes where artificial systems fail. The project builds on the internationally recognized leadership of the PI in the fields of physiology and computational modeling, combined with the expertise of the Co-Investigator in psychophysics. Building on these highly complementary fields and several technical innovations, we hope to promote a novel view of auditory perception and cognition. We aim also to contribute significantly to translational research in the domain of signal processing for clinical hearing aids, given that many current limitations are not technological but rather conceptual. The project will finally result in the creation of laboratory facilities and an intellectual network unique in France and rare in all of Europe, combining cognitive, neural, and computational approaches to auditory neuroscience.
Max ERC Funding
3 199 078 €
Duration
Start date: 2012-10-01, End date: 2018-09-30
Project acronym ADDECCO
Project Adaptive Schemes for Deterministic and Stochastic Flow Problems
Researcher (PI) Remi Abgrall
Host Institution (HI) INSTITUT NATIONAL DE RECHERCHE ENINFORMATIQUE ET AUTOMATIQUE
Call Details Advanced Grant (AdG), PE1, ERC-2008-AdG
Summary The numerical simulation of complex compressible flow problem is still a challenge nowaday even for simple models. In our opinion, the most important hard points that need currently to be tackled and solved is how to obtain stable, scalable, very accurate, easy to code and to maintain schemes on complex geometries. The method should easily handle mesh refinement, even near the boundary where the most interesting engineering quantities have to be evaluated. Unsteady uncertainties in the model, for example in the geometry or the boundary conditions should represented efficiently.This proposal goal is to design, develop and evaluate solutions to each of the above problems. Our work program will lead to significant breakthroughs for flow simulations. More specifically, we propose to work on 3 connected problems: 1-A class of very high order numerical schemes able to easily deal with the geometry of boundaries and still can solve steep problems. The geometry is generally defined by CAD tools. The output is used to generate a mesh which is then used by the scheme. Hence, any mesh refinement process is disconnected from the CAD, a situation that prevents the spread of mesh adaptation techniques in industry! 2-A class of very high order numerical schemes which can utilize possibly solution dependant basis functions in order to lower the number of degrees of freedom, for example to compute accurately boundary layers with low resolutions. 3-A general non intrusive technique for handling uncertainties in order to deal with irregular probability density functions (pdf) and also to handle pdf that may evolve in time, for example thanks to an optimisation loop. The curse of dimensionality will be dealt thanks Harten's multiresolution method combined with sparse grid methods. Currently, and up to our knowledge, no scheme has each of these properties. This research program will have an impact on numerical schemes and industrial applications.
Summary
The numerical simulation of complex compressible flow problem is still a challenge nowaday even for simple models. In our opinion, the most important hard points that need currently to be tackled and solved is how to obtain stable, scalable, very accurate, easy to code and to maintain schemes on complex geometries. The method should easily handle mesh refinement, even near the boundary where the most interesting engineering quantities have to be evaluated. Unsteady uncertainties in the model, for example in the geometry or the boundary conditions should represented efficiently.This proposal goal is to design, develop and evaluate solutions to each of the above problems. Our work program will lead to significant breakthroughs for flow simulations. More specifically, we propose to work on 3 connected problems: 1-A class of very high order numerical schemes able to easily deal with the geometry of boundaries and still can solve steep problems. The geometry is generally defined by CAD tools. The output is used to generate a mesh which is then used by the scheme. Hence, any mesh refinement process is disconnected from the CAD, a situation that prevents the spread of mesh adaptation techniques in industry! 2-A class of very high order numerical schemes which can utilize possibly solution dependant basis functions in order to lower the number of degrees of freedom, for example to compute accurately boundary layers with low resolutions. 3-A general non intrusive technique for handling uncertainties in order to deal with irregular probability density functions (pdf) and also to handle pdf that may evolve in time, for example thanks to an optimisation loop. The curse of dimensionality will be dealt thanks Harten's multiresolution method combined with sparse grid methods. Currently, and up to our knowledge, no scheme has each of these properties. This research program will have an impact on numerical schemes and industrial applications.
Max ERC Funding
1 432 769 €
Duration
Start date: 2008-12-01, End date: 2013-11-30
