ERC FUNDED PROJECTS

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.

724 992 €

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

Polar materials, such as piezoelectrics and ferroelectrics are essential to our modern life, yet they are mostly developed by trial-and-error. Their properties overwhelmingly depend on the defects within them, the majority of which are hidden in the bulk. The road to better materials is via mapping these defects, but our best tool for it – piezoresponse force microscopy (PFM) – is limited to surfaces. 3D-PXM aims to revolutionize our understanding by measuring the local structure-property correlations around individual defects buried deep in the bulk. This is a completely new kind of microscopy enabling 3D maps of local strain and polarization (i.e. piezoresponse) with 10 nm resolution in mm-sized samples. It is novel, multi-scale and fast enough to capture defect dynamics in real time. Uniquely, it is a full-field method that uses a synthetic-aperture approach to improve both resolution and recover the image phase. This phase is then quantitatively correlated to local polarization and strain via a forward model. 3D-PXM combines advances in X-Ray optics, phase recovery and data analysis to create something transformative. In principle, it can achieve spatial resolution comparable to the best coherent X-Ray microscopy methods while being faster, used on larger samples, and without risk of radiation damage. For the first time, this opens the door to solving how defects influence bulk properties under real-life conditions. 3D-PXM focuses on three types of defects prevalent in polar materials: grain boundaries, dislocations and polar nanoregions. Individually they address major gaps in the state-of-the-art, while together making great strides towards fully understanding defects. This understanding is expected to inform a new generation of multi-scale models that can account for a material’s full heterogeneity. These models are the first step towards abandoning our tradition of trial-and-error, and with this comes the potential for a new era of polar materials.

1 496 941 €

Start date: 2019-01-01, End date: 2023-12-31

ACADEMIA proposes a pioneering study of a neglected corpus of manuscripts stemming from the practice of quodlibetal debates held at Faculties of Arts of European universities, flourishing from the 14th to the early 16th century. As prescribed by the university statutes, dozens of professors participated periodically in these unique collective works of the Middle Ages, which encompassed all the disciplines pursued at the university, from logic to medicine to theology. The PI hypothesises that the professors presented at the hitherto mostly ignored quodlibets their recent scientific innovations, which they then published in the first collective volumes of European academia. The PI thus proposes a novel theoretical framework for understanding the quodlibets: they stand at the origin of the modern concept of science as a collective intellectual enterprise, similar to modern conferences and the subsequent dissemination of results. This makes them and their written form critical for understanding European intellectual and scientific traditions, both past and present. ACADEMIA’s ambition is to establish the corpus of these debates as a new field of study through an extensive examination of manuscripts, thus filling a substantial gap, radically extending the fields of the history of universities and intellectual history, and reconstructing the roots of the modern practice of fostering collective science. A complex analysis of the corpus will bring about a substantial change in our understanding of medieval practices of the production and sharing of knowledge. Aiming to examine the quodlibets as a phenomenon successively interconnecting European intellectual space, ACADEMIA focuses on fourteen universities at which the PI has identified the tradition so far and on their mutual relations and development. ACADEMIA employs an interdisciplinary team and an innovative combination of approaches from history, codicology, palaeography, philology, hermeneutics and Digital Humanities.

1 260 485 €

Start date: 2021-07-01, End date: 2026-06-30

"I propose a systematic study of the type of genetic variation enabling adaptation and factors that limit rates of adaptation in natural populations. New methods will be developed for analysing data from experimental evolution and population genomics. The methods will be applied to state of the art data from both fields. Adaptation is generated by natural selection sieving through heritable variation. Examples of adaptation are available from the fossil record and from extant populations. Genomic studies have supplied many instances of genomic regions exhibiting footprint of natural selection favouring new variants. Despite ample proof that adaptation happens, we know little about beneficial mutations– the raw stuff enabling adaptation. Is adaptation mediated by genetic variation pre-existing in the population, or by variation supplied de novo through mutations? We know even less about what factors limit rates of adaptation. Answers to these questions are crucial for Evolutionary Biology, but also for believable quantifications of the evolutionary potential of populations. Population genetic theory makes predictions and allows inference from the patterns of polymorphism within species and divergence between species. Yet models specifying the fitness effects of mutations are often missing. Fitness landscape models will be mobilized to fill this gap and develop methods for inferring the distribution of fitness effects and factors governing rates of adaptation. Insights into the processes underlying adaptation will thus be gained from experimental evolution and population genomics data. The applicability of insights gained from experimental evolution to comprehend adaptation in nature will be scrutinized. We will unite two very different approaches for studying adaptation. The project will boost our understanding of how selection shapes genomes and open the way for further quantitative tests of theories of adaptation."

1 159 857 €

Start date: 2013-04-01, End date: 2018-03-31