Dr Harry Cliff is a particle physicist from the University of Cambridge who works on the Large Hadron Collider, the world’s largest scientific experiment, at CERN near Geneva. Harry studies extremely rare particle decays in an attempt to find out more about the particles that make up our Universe and the laws that govern their behaviour. His TED talk, "Have We Reached the End of Physics", has been viewed more than 2.3 million times. Harry is also an exhibition curator at the Science Museum, where he co-curated the critically acclaimed "Collider" exhibition, and is currently working on a new exhibition telling the story of humankind’s changing relationship with the Sun.