Edward Witten is one of the worlds preeminent string theorists. Among his many accomplishments, he is widely known for showing how five different variations of string theory all belong within a single framework. His awards range from a MacArthur \'genius grant\' to the Fields Medal - the highest honour in the world of mathematics. Professor Witten will examine key discoveries made by physicists in the 20th century such as the detection of antimatter. He will then describe how many of todays leading scientists are working at the high energy frontier of elementary particle accelerators in their quest to uncover the quantum structures of space and time.