All matter was pressed together in an almost incomprehensibly small area. Particles that we can only see today in large accelerator systems such as the LHC at CERN were present and interacted with each other and with more common matter through the four fundamental forces: electromagnetism, gravity, the weak and the strong nuclear force. Therefore, the study of the evolution of the universe, cosmology, and of the world's smallest components, particle physics, is completely inextricably linked together, and therefore both subjects are among the most fascinating imaginable.
The research in particle and astroparticle physics illuminates not only the origin and final fate of the universe, but also black holes, neutrinos and dark matter, which are among the least understood phenomena today. Along the way, the actual mathematical structure that all physics uses to describe the universe around us is developed.