Jim Al-Khalili investigates the amazing science of gravity, recreating groundbreaking experiments, including the moment when Galileo first worked out how to measure it. He investigates gravity waves, finds out from astronauts what it's like to live without gravity, sets out to find where in Britain gravity is weakest and so where we weigh the least, and helps design a smartphone app that volunteers use to demonstrate how gravity affects time and makes us age at slightly different rates.
Join scientists as they grab light from across the universe to prove quantum entanglement is real. Einstein called it "spooky action at a distance", but today quantum entanglement is poised to revolutionize technology from computers to cryptography. Physicists have gradually become convinced that the phenomenon two subatomic particles that mirror changes in each other instantaneously over any distance is real. But a few doubts remain. NOVA follows a ground-breaking experiment in the Canary Islands to use quasars at opposite ends of the universe to once and for all settle remaining questions.
Richard Feynman was one of the most brilliant theoretical physicists and original thinkers of the 20th century. He rebuilt the theory of quantum electrodynamics, and it was for this work that he won the Nobel Prize in 1965. In 1981, he gave Horizon a candid interview, talking about many things close to his heart.
Light always travels at a speed of 299,792,458 meters per second. But if you're in motion too, you're going to perceive it as traveling even faster -- which isn't possible! In this second installment of a three-part series on space-time, CERN scientists Andrew Pontzen and Tom Whyntie use a space-time diagram to analyze the sometimes confounding motion of light.
Helen Czerski ventures beyond the visible spectrum in the final (and best) episode in this vibrant little series, showing how electromagnetic radiation is so much broader than the narrow slice of reality we see with our eyes. Before delving into the details of UV, infrared and x-rays, Dr Czerski explores colour subjectivity by trying on a dress that recently divided the internet — to some it appeared blue and black, to others white and gold. It's a perfect fit. It's also a neat analogy of how people can have opposing views but both swear blind that their perspective is correct. The series ends with some amazing imaging techniques that show our bodies in a whole new light.
In the first episode, Helen seeks out the colours that turned planet Earth multicoloured. To investigate the essence of sunlight Helen travels to California to visit the largest solar telescope in the world. She discovers how the most vivid blue is formed from sulfur atoms deep within the Earth's crust and why the presence of red ochre is a key sign of life. In gold, she discovers why this most precious of metals shouldn't even exist on the surface of the planet and in white, Helen travels to one of the hottest places on Earth to explore the role salt and water played in shaping planet Earth.