Hunting invisibles: dark sectors, dark matter and neutrinos
Despite huge progress in particle physics and cosmology, most of the Universe’s building blocks and how they function remain hidden to us: Neutrinos are the most abundant known fermion but the reasons why they have mass and mix are unexplained; we have evidence of Dark Matter but we do not even know which particle makes it up;  particles and antiparticles show to behave differently (the so-called CP-violation) without a compelling reason; we see that in the Universe there is mostly matter and very little antimatter, but we do not know why this is the case. Symmetries and their breaking will be the guiding principle to address those questions. HIDDeN will focus on revealing the (a)symmetries we have yet to discover, hence hidden (a)symmetries, and the particles on which they act, in particular the invisible sector, made of neutrinos, dark matter and other elusive particles. We will explore simultaneously the puzzles related to the CP symmetry in the lepton sector as well as in strong-interactions (the latter leading to axions and axion-like particles), (a)symmetries in the mass and mixing patterns of known particles, (a)symmetries responsible for the dark matter stability and its interactions. And we will address a key question: are all these sectors part of a new HIDDeN sector whose discovery will lead us to the New Standard Model? 

The mission of the HIDDeN ITN is to train the new generation of researchers to address these most fundamental questions via an ambitious multidisciplinary research and training program. We focus on phenomenological studies and include crucial links to experiments and industrial partners. We bundle world leadership in phenomenology research and our network includes representatives of key-experiments and laboratories on the field, such as CERN, Fermilab, SuperKamiokande, ADMX. An innovative aspect is the integration of a dedicated training program in outreach and journalism focussed on the Invisible Universe.