In the summer of 1939 Albert Einstein was on holiday in a small resort town on the tip of Long Island. His peaceful summer, however, was about to be shattered by a visit from an old friend and colleague from his years in Berlin. The visitor was the physicist Leo Szilard. He had come to tell Einstein that he feared the Nazis could soon be in possession of a terrible new weapon and that something had to be done.
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
Early Earth was a canvas for the vast new palette of the colours of life, with the diversity of human skin tones telling the story of how humanity spread and ultimately conquered the planet. Dr Helen Czerski explores the true masters of colour - which are often the smallest and most elusive - travelling to the mountains of Tennessee to witness the colourful mating display of fireflies, and revealing the marine creatures that can change the colour of their skin in order to hide from the world.
When you think about Einstein and physics, E=mc^2 is probably the first thing that comes to mind. But one of his greatest contributions to the field actually came in the form of an odd philosophical footnote in a 1935 paper he co-wrote -- which ended up being wrong.
We float along the river of time. But does that river have a source? Where did time come from? Some believe time and space are one thing, and the Big Bang started the cosmic clock. Others believe the universe existed for almost half a million "years" before light could move and time began. Still others say time is older than our universe. But what if time itself is an illusion? Incredible new experiments may hold the answer. One groundbreaking experiment gives us the power to punch holes in time…and another may create a machine that operates outside time’s boundaries!