Astroparticle physics and cosmology

Our knowledge of the evolution of the universe has taken remarkable strides in recent years. While the gravitational force is known to provide a very accurate description of the formation of large scale structure, like galaxy clusters, at various epochs the interplay with particle physics has been crucial. Indeed, our current knowledge of the Cosmic Microwave Background Radiation (CMB), combined with other data such as the apparent acceleration of distant supernovae, suggests that the unievrse is well described by an early period of inflation, followed by a hot big bang, and most recently a new period acceleration.

Moreover, the constituents are predominantly not ordinary matter, but dark matter, inferred from the rotation curves of visible matter in galaxies, and an even stranger substance known as dark energy, which is driving the current accelerating phase, and in fact forms around 70% of the matter density in the standard cosmological model. This may well be in the form of Einstein's famous cosmological constant. Particle physics plays an important role in describing the period of Big Bang Nucleosynthesis, and can also provide new candidates for dark matter. The latter aspect has led to a rapid expansion in the field now known as astroparticle physics.