The nascent field of gravitational wave (GW) science will be an interdisciplinary subject, enriching different branches of physics, yet the associated computational challenges are enormous. Faithful theoretical templates are a compulsory ingredient for successful data analysis and reliable physical interpretation of the signals. This is critical, for instance, to study the equation of state of neutron stars, the nature of black holes, and binary formation channels. However, while current templates for compact binary sources may be sufficient for detection and crude parameter estimation, they are too coarse for precision physics with GW data. We then find ourselves in a situation in which, for key processes within empirical reach, theoretical uncertainties may dominate. To move forward, profiting the most from GW observations, more accurate waveforms will be needed. I have played a pioneering role in the development and implementation of a new formalism, known as the ‘effective field theory approach’, which has been instrumental for the construction of the state-of-the-art GW template bank. The goal of my proposal is thus to redefine the frontiers of analytic understanding in gravity through the effective field theory framework. Even more ambitiously, to go beyond the current computational paradigm with powerful tools which have been crucial for `new-physics' searches at the Large Hadron Collider. The impact of the high-accuracy calculations I propose to undertake will be immense: from probes of dynamical spacetime and strongly interacting matter, to the potential to discover exotic compact objects and ultra-light particles in nature. Furthermore, GW observations scan gravity in a regime which is otherwise unexplored. Consequently, the coming decade will tell whether Einstein's theory withstands precision scrutiny. In summary, my program will provide novel techniques and key results that will enable foundational investigations in physics through GW precision data.

Without doubt, one of the most intriguing questions in modern astronomy is whether habitable planets, potentially supporting life, exist outside our solar system. In the upcoming era of large aperture astronomical telescopes and highly stable spectrometers, answering these questions is for the first time a tangible possibility. Successfully finding answers to these questions will, however, critically rely on non-incremental advances in astronomical instrumentation. The objective of the proposed research is, developing and demonstrating novel photonic-chip laser frequency combs to support the revolutionary advances in astronomical precision spectroscopy required to enable detection and characterization of habitable Earth-like planets. Habitable exo-planets can be discovered by observing minute wavelength-shifts in the optical spectra of their host stars. These wavelength-shifts are so small that exquisitely accurate and precise wavelength-calibration of astronomical spectrometers is required. It has been recognized that laser frequency combs (LFCs), broadband spectra of laser-lines with absolutely-known optical frequencies, can provide the required level of precision, provided the LFC’s lines can be resolved by the spectrometer. Generating such frequency comb spectra (“astrocombs�) with resolvable lines remains, however, exceedingly challenging. Here, we will develop and demonstrate a novel class of photonic-chip microresonator-based astrocombs that can naturally provide broadband spectra of resolvable lines, potentially from visible to mid-infrared wavelengths, thereby overcoming key challenges in astrocomb generation. In order to achieve this goal we will pursue radically different microresonator designs and new nonlinear optical regimes in order to overcome long-standing limitation in microresonator physics. The developed astrocombs will not only be pivotal to astronomy but indeed can directly and profoundly impact the way we transfer data, monitor our environm

Four decades after its prediction, the axion remains the most compelling solution to the strong CP problem and a well motivated dark matter candidate, inspiring several ultrasensitive experiments based on axion-photon mixing. The experimental landscape for axion searches is evolving extremely fast: consolidated detection techniques are now facing next-generation experiments with ambitious sensitivity goals, while novel and ingenious detection concepts promise to open for exploration new ranges of parameter space previously considered unreachable. AXIONRUSH deals with an ambitious program to reshape the parameter space of the QCD axion by developing new model building directions and by revisiting from an ultraviolet perspective axion couplings to photons, nucleons, electrons, including also flavour and CP violating ones. The main goal of AXIONRUSH is to bridge theoretical aspects of axion physics with experiments and to provide a global comparison of general axion models with experimental sensitivities and astrophysical bounds. The development of these new theoretical tools will enlarge the physics scopes of the axion experimental program at DESY, Hamburg, by further addressing specific research goals related to the experiments ALPS-II, IAXO, MADMAX and Belle II. A complementary objective of AXIONRUSH is to investigate scenarios where the Peccei Quinn mechanism is embedded into grand unified theories. The latter provide a predictive framework for narrowing down the axion mass range, with a potential impact on the scanning strategy of the axion dark matter experiments CASPER-Electric and ABRACADABRA. A major intention of this latter objective is the construction of a minimal, unified scenario aiming at a self-contained description of particle physics, from the electroweak scale to the Planck scale, and cosmology, from inflation until today.

It is now firmly established that most of the matter in the Universe is in the form of the mysterious dark matter, contributing more than 80% to the total amount of matter. However, despite tremendous theoretical and experimental efforts over the past few decades, dark matter remains elusive and one of the great unknowns until today. To identify the nature of dark matter is evidently of fundamental importance and one of the top priorities in science today. The quest for dark matter is inherently multi disciplinary with strong roots in particle physics, astrophysics and cosmology, providing profound connections between these different disciplines. This project aims at exploring new avenues towards solving the dark matter puzzle, with a particular focus on a few select groundbreaking topics. These are centered around (i) theoretical dark matter model building, (ii) the study of new collider signatures, (iii) developing new techniques for the comparison and interpretation of direct detection experiments and (iv) identifying astrophysical probes which constrain or give evidence for dark matter self-interactions. Given the impressive increase in sensitivity of upcoming dark matter experiments as well as the upcoming high energy run of the Large Hadron Collider, there is no doubt that the era of data has begun for dark matter searches and that we can expect putative signals rather than exclusion limits for the near future. It is therefore extremely important to bring together different fields and exploit the complementarity of different search strategies to maximise the amount of information gained from a successful detection. This inherently multi disciplinary approach is at the heart of the current project, which can rely on a well established network of collaborators and will bring together excellent young physicists with different backgrounds to form a small but well structured research group which will significantly advance dark matter phenomenology in Europe.