The expanding universe is a complicated place. During inflation the universe expanded faster than light, but that's something that actually happens all the time, it's happening right now. This doesn't violate Einstein's theory of relativity since nothing is moving through space faster than light, it's just that space itself is expanding such that far away objects are receding rapidly from each other. Common sense would dictate that objects moving away from us faster than light should be invisible, but they aren't. This is because light can travel from regions of space which are superluminal relative to us into regions that are subluminal. So our observable universe is bigger than our Hubble sphere - it's limited by the particle horizon, the distance light could travel to us since the beginning of time as we know it.
2014 • Astronomy
Imagine a game of dice: if the biggest number rolled is one, two, three, or four, player 1 wins. If the biggest number rolled is five or six, player 2 wins. Who has the best probability of winning the game? Leonardo Barichello explains how probability holds the answer to this seemingly counterintuitive puzzle.
John Hendricks, founder of the Discovery Channel and CuriosityStream, explores the largest numbers in the Universe and describes how the average person might be able to comprehend their scale. How can a normal person understand "quadrillion" in real terms?
By our third year, most of us will have learned to count. Once we know how, it seems as if there would be nothing to stop us counting forever. But, while infinity might seem like an perfectly innocent idea, keep counting and you enter a paradoxical world where nothing is as it seems.
From a bee’s hexagonal honeycomb to the elliptical paths of planets, symmetry has long been recognized as a vital quality of nature. Einstein saw symmetry hidden in the fabric of space and time. The brilliant Emmy Noether proved that symmetry is the mathematical flower of deeply rooted physical law. And today’s theorists are pursuing an even more exotic symmetry that, mathematically speaking, could be nature’s final fundamental symmetry: supersymmetry.
Without us noticing, modern life has been taken over. Algorithms run everything from search engines on the internet to satnavs and credit card data security - they even help us travel the world, find love and save lives. Professor Marcus du Sautoy demystifies the hidden world of algorithms. By showing us some of the algorithms most essential to our lives, he reveals where these 2,000-year-old problem solvers came from, how they work, what they have achieved and how they are now so advanced they can even programme themselves.
2015 • Math
Stuff happens. The weather forecast says it’s sunny, but you just got drenched. You got a flu shot—but you’re sick in bed with the flu. Your best friend from Boston met your other best friend from San Francisco. Coincidentally. What are the odds? Risk, probability, chance, coincidence—they play a significant role in the way we make decisions about health, education, relationships, and money. But where does this data come from and what does it really mean?