ERC FUNDED PROJECTS

2D nanomaterials hold immense technological promise thanks to extraordinary intrinsic properties such as ultra-high conductivity, strength and unusual semiconducting properties. Our understanding of how these extremely thin and flexible objects are processed in flow is however inadequate, and this is hindering progress towards true market applications. When processed in liquid environments to make nanocomposites, conductive coatings and energy storage devices, 2D nanomaterials tend to fold and break owing to strong shear forces produced by the mechanical agitation of the liquid. This can lead to poorly-oriented, crumpled sheets of small lateral size and therefore of low intrinsic value. Orientation is also a major issue, as ultra-flexible materials are difficult to extend and align. In this project, I will develop nanoscale fluid-structure simulation techniques to capture with unprecedented resolution the unsteady deformation and fracture dynamics of single and multiple sheets in response to the complex hydrodynamic load produced by shearing flows. In addition, I will demonstrate via simulations new strategies to exploit capillary forces to structure 2D nanomaterials into 3D constructs of desired morphology. To guide the simulations and explore a wider parameter space than allowed in computations, I will develop conceptually new experiments on “scaled-up 2D nanomaterials”, macroscopic particles having the same dynamics as the nanoscopic ones. The simulations will include continuum treatments and atomistic details, and will be analysed within the theoretical framework of microhydrodynamics and non-linear solid mechanics. By uncovering the physical principles governing flow-induced deformation of 2D nanomaterials, this project will have a profound impact on our ability to produce and process 2D nanomaterials on large scales.

1 453 779 €

Start date: 2017-04-01, End date: 2022-03-31

Flight is thought to be one of the most energetically costly of bird activities. These costs matter by virtue of their magnitude, as factors affecting flight costs can have a disproportionate impact on the overall energy balance. Flight costs are fundamentally linked to airflows, as well as behavioural responses to them, because birds react to horizontal and vertical currents by changing flight mode (i.e. flapping/ gliding), speed and route. Even minor route adjustments can radically affect the flow conditions that birds experience due to the uniquely dynamic and heterogeneous nature of the aerial environment. Yet our understanding of how airflows impact birds is in its infancy, being constrained by a lack of information on the metabolic costs of flight. Currently, the main methods for measuring flight costs in the laboratory either restrain the bird (thereby increasing energy expenditure) or suffer from low resolution, and field methods do not allow costs to be resolved in relation to fine scale movement paths. FLIGHT will use interdisciplinary approaches, integrating laboratory and field techniques, to address these grand challenges. Breakthrough methodologies will be used to (1) measure the costs of unrestrained bird flight in the laboratory and (2) derive a new proxy for power use in flight that is linked to flight performance, using accelerometry measurements from cutting-edge data loggers. Loggers will then be (3) deployed on wild birds to quantify their responses to airflows and the energetic consequences over fine scales. This will provide completely novel, mechanistic insight into the way the physical environment impacts flight costs, and (4) enable variation in flight–related energy expenditure to be modelled geographically and seasonally in model species. Overall, FLIGHT will provide new macro-ecological insight into relationships between bird distributions and flow conditions and inform assessments of how birds may be affected by changing wind regimes.

1 996 043 €

Start date: 2017-04-01, End date: 2022-03-31

A period is a complex number defined by the integral of an algebraic differential form over a region defined by polynomial inequalities. Examples include: algebraic numbers, elliptic integrals, and Feynman integrals in high-energy physics. Many problems in mathematics can be cast as a statement involving periods. A deep idea, based on Grothendieck's philosophy of motives, is that there should be a Galois theory of periods, generalising classical Galois theory for algebraic numbers. This reposes on inaccessible conjectures in transcendence theory, but these can be circumvented in many important cases using an elementary notion of motivic periods. This allows one to set up a working Galois theory of periods in many situations of arithmetic and physical interest. These ideas grew out of the PI's recent proof of the Deligne-Ihara conjecture, in which the Galois theory of multiple zeta values was worked out. Multiple zeta values are one of the most fundamental families of periods, and their Galois group plays an important role in mathematics: it is conjecturally equal to Drinfeld's Grothendieck-Teichmuller group, the stable derivation algebra on moduli spaces of curves, and the Galois group of mixed Tate motives over the integers. It occurs in deformation quantization, the homology of the graph complex, and the Kashiwara-Vergne problem, as well as having numerous connections to string theory, and quantum field theory. The goal of this proposal is to generalise this picture. Periods of moduli spaces of curves, multiple L-functions of modular forms, and Feynman amplitudes in quantum field and string theory should each have their own Galois theory which is yet to be worked out. This is completely uncharted territory, and will have numerous applications to number theory, algebraic geometry and physics.

1 997 959 €

Start date: 2017-03-01, End date: 2022-02-28

The trade-off between survival and reproduction lies at the core of the evolutionary theory of ageing. Removal of germ cells extends somatic lifespan implying that reduced reproduction frees up resources for survival. Remarkably, however, the disruption of germline signalling increases lifespan without the obligatory reduction in fecundity, thus challenging the key role of the survival-reproduction trade-off. Recent breakthroughs suggest that protection and repair of the genome and the proteome of the germ cells is costly and compromised germline maintenance increases mutation rate, which can reduce offspring fitness. Thus, expensive germline maintenance can be a missing link in the puzzle of cost-free lifespan extension. This hypothesis predicts that when germline signalling is manipulated to increase investment into somatic cells, the germline maintenance will suffer resulting in increased mutation rate and reduced offspring fitness, even if total fecundity is unaffected. I propose a research program at the interface of evolutionary biology and biogerontology that focuses on phenotypic and evolutionary costs of germline maintenance. First, I will genetically manipulate germline signalling to boost investment into soma and estimate mutation rate and competitive fitness of the resulting offspring using Caenorhabditis elegans nematodes. Second, I will employ experimental evolution in nematodes to assess the long-term evolutionary costs of increased germline maintenance. Third, I will use germline transplantation in zebrafish Dario rerio to directly test whether germline proliferation reduces investment into soma in a vertebrate. Understanding how increased investment into the soma damages the germline and reduces offspring fitness will provide a major advance in our understanding of ageing evolution and will have serious implications for applied research programs aimed at harnessing the power of germline signalling to postpone ageing.

2 000 000 €

Start date: 2017-09-01, End date: 2022-08-31