— 24/03/2022 // Odjel za fiziku, Osijek
Our understanding of the physical universe is based on four types of cosmic messengers: photons, cosmic rays, neutrinos, and gravitational waves. We call them astroparticles. For each type of messenger I try to answer: What are they? (What is their nature?); Where do they come from? (What are their sources?); How do we detect them? (What instruments do we use to observe them?). Additionally, I show two fascinating facts about the universe: (1) expansion of the universe is accelerated; (2) the universe is mostly made of dark energy and dark matter with 4% of normal (baryonic) matter only (3.6% is cosmic gas and dust and, believe it or not, just 0.4% are stars).