The Cosmic Ballet

Every decade astronomers utilise new technology to make ever larger maps of the 3-dimensional distribution of galaxies in the local universe. These reveal that the galaxies trace out a beautiful Cosmic Web of voids, filaments, walls and clusters. Using past and future surveys, in which Durham researchers were and are involved, I will explain how these galaxy surveys are constructed and what they tell us about the Big Bang, the origin of structure, the matter-energy content (dark matter and dark energy) and the possible ultimate fate of the Universe.

Black holes are a key plot device in science fiction and fantasy, used as wormholes through space and time! Here I'll separate out the fact from the fiction, and talk about how black holes went from a speculative extension of Einstein's gravity to a mainstream observational science via the development of rockets at the start of the space age.

Cosmologists tell us that 85% of all matter in the Universe is some mysterious ‘dark matter’ that you won’t find on the periodic table. I will explain how dark matter became a key ingredient in our understanding of the cosmos, and discuss some of the work that is being done to figure out what it is. In particular, I will show how a collision of two galaxy clusters (known as the Bullet Cluster) is being used to shine a light on the nature of this mysterious stuff.