"This talk will mostly be stories... I want to tell you about Albert Einstein, and about his theory of relativity - what it is, why he was thinking about it and also about some of the very latest developments that have happened just this year."

This talk by Professor David Tong (Department of Applied Mathematics and Theoretical Physics, University of Cambridge) was originally given to an audience of Year 12 A-level Maths students (aged 16-17). The talk formed part of a mathematics enrichment day we organised with a special focus on encouraging the development of mathematical thinking. It was recorded on 27 June 2014.