QGRANT · Quantum GRavity seArches with Neutrino Telescopes

Quantum GRavity seArches with Neutrino Telescopes

The QGRANT project operates at the frontier of theoretical and experimental physics, tackling one of the most profound questions in science: the reconciliation of the Standard Model (SM) of particle physics and General Relativity (GR) into a comprehensive theory of Quantum Gravity (QG). Although both SM and GR independently provide extremely accurate descriptions of nature at micro and macro scales, respectively, they are fundamentally incompatible. Their merger is anticipated at the Planck scale, far beyond current experimental reach. Nevertheless, certain predicted effects of QG, such as quantum decoherence (QD) and violations of discrete and space-time symmetries like Lorentz invariance (LI), might be observable at lower energies that are accessible to modern particle physics experiments. Neutrino telescopes such as IceCube, ANTARES, and KM3NeT offer a unique window into these physics regimes due to their sensitivity across a broad energy range and baseline, functioning as natural interferometers for probing QG-induced effects. Specifically, deviations in neutrino oscillation patterns that could arise from QD or Lorentz invariance violation (LIV) are prime targets for experimental investigation. Exploring these deviations not only constrains QG models but also deepens our understanding of the structure of space-time itself. Motivation and Pathway to Impact: The core motivation of QGRANT is to perform the first joint, global analysis for QG signatures in neutrino oscillation data acquired from IceCube, ANTARES, and KM3NeT. The approach includes investigating both QD and LIV effects, aiming to set unprecedented limits on these phenomena, and, incidentally, to probe the fundamental properties of neutrinos such as their Dirac or Majorana nature and potential CPT violation. The project's scientific pathway involves: 1) Enriching the science scope of ANTARES and KM3NeT by performing new QG analyses with 10+ years of data and evaluating the sensitivity of freshly deployed KM3NeT modules. 2) Reinforcing the role of neutrinos as probes for quantum gravity through strong cooperation with theoretical QG experts, particularly those specializing in Loop Quantum Gravity (LQG), and combining the strengths of three global neutrino observatories in a first-of-its-kind analysis. Political and Strategic Context: This research aligns with major international scientific priorities in astroparticle physics—pushing the boundaries of fundamental knowledge and experimental techniques. By leveraging the unique environment of the Erlangen Centre for Astroparticle Physics (ECAP), which hosts active groups for all three neutrino telescopes and a close partnership with quantum gravity theory groups, QGRANT maximizes both the scientific and strategic potential of European and global collaborations in this field. The MSCA fellowship provides the necessary international and interdisciplinary framework, fostering long-term human capital development, technology transfer, and global research networks within the European and wider scientific community. Scale and Significance of Expected Impact The anticipated impacts are multifaceted and of significant scale: 1) Scientific Impact: Setting new limits on QG phenomena that will influence theoretical model-building and guide future experimental efforts. Results from the joint analysis will be the most sensitive yet, and may lead to the first observation of QG signatures or improved constraints. 2) Strategic Impact: Deepening collaboration among major neutrino observatories and between experimental and theoretical communities, laying the groundwork for next-generation analyses and discoveries. 3) Societal and Outreach Impact: Through open access publishing, outreach programs, and integration of machine learning tools, the project will communicate advances to both scientific and general audiences. The development and release of the Quantum Gravity Neutrino Tool (QGNT) as open-source software will further empower the wider research community. In summary, QGRANT sets the scene for a transformational advance in both physics and research culture, promising new insights into quantum gravity, neutrino physics, and fundamental symmetries in nature, with broad impact on international science and society.

Data: CORDIS, © European Union