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.
Ice is one of the strangest, most beguiling and mesmerising substances in the world. Full of contradictions, it is transparent, yet it can glow with colour, it is powerful enough to shatter rock, but it can melt in the blink of an eye. It takes many shapes, from the fleeting beauty of a snowflake to the multimillion-tonne vastness of a glacier and the eeriness of the ice fountains of far-flung moons. Science writer Dr Gabrielle Walker has been obsessed with ice ever since she first set foot on Arctic sea ice. In this programme, she searches out some of the secrets hidden deep within the ice crystal to try to discover how something so ephemeral has the power to sculpt landscapes, to preserve our past and inform our future.
2011 • Physics
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.
2017 • Physics
You exist. You shouldn’t. Stars and galaxies and planets exist. They shouldn’t. The nascent universe contained equal parts matter and antimatter that should have instantly obliterated each other, turning the Big Bang into the Big Fizzle. And yet, here we are: flesh, blood, stars, moons, sky. Why? Come join us as we dive deep down the rabbit hole of solving the mystery of the missing antimatter.
Extra dimensions of space — the idea that we are immersed in hyperspace — may be key to explaining the fundamental nature of the universe. Relativity introduced time as the fourth dimension, and Einstein’s subsequent work envisioned more dimensions still — but ultimately hit a dead end. Modern research has advanced the subject in ways he couldn’t have imagined. John Hockenberry joins Brian Greene, Lawrence Krauss, and other leading thinkers on a visual tour through wondrous spatial realms that may lie beyond the ones we experience.