The interactions that shape matter. We are in a golden age of quantum matter research, with exotic new materials and material properties being discovered every year. To understand all these new forms of matter, to predict how they will behave, and to use them, we need to be able to calculate how their unique qualities arise from the interactions between the many microscopic quantum particles they are made of. In this project, researchers investigate how interactions between quantum paricles depend on their speeds, magnetisation, shapes, or other properties, and how this dependence ultimately grants new materials their characteristic traits.

The perennial appeal of condensed matter science lies in its apparently limitless set of possibilities. Combining different sorts of constituent particles in different ways leads to myriads of remarkable phenomena; one cannot help but wonder that of these countless possibilities, only a few are known, and the simplest understood. Our problem is that the predictive power of our standard approaches is quickly rendered inapplicable by the potent mixture of quantum mechanics, interparticle interactions and reduced dimensionality. The ubiquitous strategy of focusing on low-energy, universal features only often lacks the depth to explain or predict important, observable and potentially useful features of key strongly-correlated systems. This proposal aims to establish a new framework for tackling strong correlations, in which universal scaling results at low energies are superseded by detailed, quantitative results valid at arbitrary energies, but in more specific circumstances. This will be achieved by capitalizing on recent breakthroughs on `pioneer systems: these `Bethe liquids find experimental realizations in forms ranging from magnetic materials and cold atomic gases to quantum dots and nanostructures. Their theoretical description will be unified into a consistent framework, bridging diverse fields from the mathematics of representation theory all the way to concrete physical applications, and offering urgently-needed, detailed quantitative calculations of many experimental observables beyond the reach of traditional methods. The theoretical foundations of Bethe liquids will in fact be robust enough to support the treatment not only of equilibrium but also of out-of-equilibrium situations, allowing detailed studies of fundamental questions relating to dynamics, decoherence, relaxation and thermalization in many-body interacting quantum systems, providing stringent new benchmarks for alternative methods, setting new challenges for experiments, and providing an altogether new way of thinking about strong correlations.

This ‘FuSE: Fundamental Sciences E-infrastructure’ proposal brings together Nikhef, the Dutch institute for subatomic physics and ASTRON, the Netherlands Institute for Radio-Astronomy, with SURF, the national e-Infrastructure provider, to build and operate a nationwide e-Infrastructure. This e-Infrastructure will serve the most data-intensive and demanding Research Infrastructures on the National Roadmap: the LHC experiments ATLAS, LHCb, and ALICE at CERN (high-energy physics), the Square Kilometre Array (SKA, radio astronomy) and KM3NeT (neutrino astrophysics) and will thereby strengthen the already unique position of The Netherlands in providing joint e-Infrastructure facilities. In the 2020’s era of Exabyte data rates, the development of this e-Infrastructure will ensure that the national computing facilities are available and affordable. Without the work of this proposal, the Dutch computing costs and demands would be much higher, or conversely, this front-line computing and research capability would be unavailable to the community. Nikhef and ASTRON each fulfil national leadership and coordination roles in these global scientific facilities. These roles are the natural consequence of the Netherlands’ strategic investment in these facilities, and as a result, these are part of the Dutch National Roadmap. The science cases for the facilities are at the heart of the strategic scientific agendas of both institutes. Towards the end of the five-year term (2021-2025) of this proposal, all three infrastructures will be acquiring data at the Exabyte scale. Large-scale computing infrastructures are needed to ensure Dutch researchers have access to the resources necessary to properly exploit the nation’s major investments in these global endeavours. The similarities between the computing infrastructure requirements coupled with the cost-benefit of collaboration have led to this proposal. Embedding the proposed joint data-processing facility in the Dutch National e-Infrastructure (DNI) is expected The science cases of the three global research infrastructures drive the content and extent of this proposal. The LHC science cases follow from the LHC Upgrade proposal (2013) which funded construction of new detectors as well as computing for the period 2014 – 2019. The upgraded detectors will be installed in the coming two years and the LHC will start running again in 2021. The proposed facility is necessary to analyse these data and extract the scientific results. For KM3NeT the science cases are equally compelling: it is the only place in Europe where neutrino oscillations and cosmic neutrinos can be studied. The science cases of interest to the Dutch community for the SKA are among the highest-priority science projects identified for this global telescope. Whilst it will take until 2026-2027 for the full science capability of SKA to ramp up to full capacity we will be building on leading Dutch expertise in LOFAR, a critical SKA pathfinder telescope, to blaze the way to significant leadership and impact from the new SKA. Given the investments that the Netherlands has made over the past 10-15 years, it is a matter of national pride that the two highest rated key science projects for SKA are the study of the Epoch of Reionisation (mapping the evolution of the first stars and galaxies) and timing pulsars to test extreme physics (of matter and gravity). Furthermore, we aim to deliver an e-Infrastructure that will be ready for the emerging field of multimessenger physics, exploiting data from a number of detectors and telescopes to enable fundamental discoveries. In the longer term, this will include yet another infrastructure on the National Roadmap: the 3rd generation gravitational waves detector, Einstein Telescope. The proposal covers the period 2021 - 2025. The total budget is M€ 28,8. Of this amount M€ 10,5 will be provided by the DNI (SURF), as the continued support of the Dutch LHC (WLCG) Tier-1. ASTRON and Nikhef will together co-fund M€ 6,4. The Roadmap request is M€ 11,9. This proposal combines the interests of three Research Infrastructures and strives towards an even stronger position for the Netherlands in these experiments in full alignment with the Dutch national e-Infrastructure.

Computing with qudits. While quantum computers offer unprecedented opportunities for speeding up certain types of computations, their development remains very challenging. We propose to take advantage of existing but unused internal structures of quantum systems, such as individual atoms, for quantum computation and studies of fundamental theories of Nature. We will develop new algorithms to achieve this and test them with one of the leading platforms for quantum computing, an array of neutral atoms cooled to temperatures close to absolute zero.

The Dutch-built Low-Frequency Array (LOFAR) is a unique radio telescope that brings together the signals from tens of thousands of antennas spread across the Netherlands and Europe. By removing various bottlenecks in data transport and data processing, we will unlock the full potential of LOFAR to make both sharp and wide-field images of radio waves arriving from outer space. We will study, for example, how stars form over cosmic time and how exoplanets are influenced by their parent star. We will also capture rare explosions from merging stars and study the extremes of the Universe.