Your Universe – the past, the present and the future!

The Universe you and I live in is large, old and expanding – in fact, it is accelerating. It is 13.8 billion years old, and the atoms and light we see all around us appear to make up no more than 5% of the overall energy budget. The remaining 95% seems to be hidden from direct sight: 25% is in the form of cold dark matter which has decided not to interact with light, but without which galaxies like our Milky Way would not have formed. The remaining 70% is an unknown form of energy known as dark energy and is driving this acceleration.

Given that we don’t know what dark matter or dark energy is, it is remarkable that the paradigm which describes our universe, based on Einstein’s General Theory of Relativity and Quantum Mechanics, seems to fit the data beautifully. We will have fun exploring your Universe. We will discuss the key moments in its evolution, including asking how it began (spoiler – we don’t know). We will ask what happened in the first fractions of a second when the Universe seems to have undergone an incredibly fast rate of expansion leading to the generation of tiny perturbations in matter, which eventually led to the structure we see on large scales. We will discuss when stars and galaxies appeared, when the Universe started accelerating, what is causing this acceleration and what is likely to happen to our Universe in the future. It is a wonderful time to be studying the Universe: new telescopes are probing its deepest parts, whilst accelerators are probing its smallest constituents. We will visit these developments. The exciting prospect is that through the physics of the early universe, these smallest and largest scales are closely connected.