Professor Christos Tsagas is a faculty member in the Physics Department at the Aristotle University of Thessaloniki, Greece and a life member of Clare Hall College at Cambridge University, UK. His research focuses on theoretical relativistic cosmology, the large-scale structure of the universe, bulk peculiar motions and relativistic electrodynamics. Over the years, professor Tsagas' work has attracted the interest of the wider audience, with related news pieces appearing in Science, Nature, der Spiegel, NBC News and New Scientist. Professor Leandros Perivolaropoulos is a distinguished researcher in theoretical cosmology at the University of Ioannina, Greece. His pioneering work on cosmic acceleration and modified gravity has significantly influenced our understanding of dark energy. His research spans theoretical cosmology, gravitational physics, and observational constraints on modified gravity theories. He has made notable contributions to the study of cosmic anisotropies and their implications for fundamental physics.