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Discovery

BBC World Servicewww.bbc.co.uk

Explorations in the world of science.

Episodes

Does infinity exist?

“Is anything in the Universe truly infinite, or is infinity something that only exists in mathematics?” This question came from father and son duo from Edinburgh in Scotland, Tom and Sorely Watson. First, we investigate the concept of infinity in mathematics with a story of mathematics, music and murder from Steven Strogatz from the Cornell University. Did you know that there are some infinities that are bigger than others? We discuss the mind-bending nature of infinity with mathematician Eugeni...

Jun 10, 201926 min

Why do we get déjà vu?

4/6 Part 1: Déjà vu "Do we know what causes déjà vu?" asks Floyd Kitchen from Queenstown in New Zealand. Drs Rutherford and Fry investigate this familiar feeling by speaking to world-leading reseacher Chris Moulin from the University of Grenoble in France and memory expert Catherine Loveday from Westminster University. Plus, they find out why early investigations classed déjà vu as a type of paranormal phenomenon. For most of us, it's a fleetingly strange experience, but for some people it can b...

Jun 03, 201926 min

Will we ever find alien life?

3/6 In this instalment of The Curious Cases of Rutherford & Fry, Hannah and Adam boldly go in search of scientists who are hunting for ET, spurred on by questions sent in by listeners across the globe, from Australia to Columbia. They start by asking how we define life and why we are obsessed with finding it on Mars. Should we be looking further out in the Solar System, and could we find space squid on the icy moon Europa? When it comes to intelligent life we may have to scout even further i...

May 27, 201927 min

Why people have different pain thresholds

2/6 "How fast can a human run and would we be faster as quadrapeds?" This question flew in via Twitter from Greg Jenner. Is there a limit to human sprinting performance? In this episode we investigate the biomechanics of running, statistical trends in human performance and which kind of monkey runs the fastest. But first, an experiment. Due to some spurious and possibly fictional injuries, neither Hannah nor Adam are fit enough to take part in a sprint trial at the University of Bath. So long-su...

May 20, 201926 min

How do instruments make music?

1/6 "We play many musical instruments in our family. Lots of them produce the same pitch of notes, but the instruments all sound different. Why is this?" asks Natasha Cook aged 11, and her Dad Jeremy from Guelph in Ontario, Canada. In this new series of The Curious Cases of Rutherford and Fry, Hannah and Adam are joined by the Curious Cases band - Matt Chandler and Wayne Urquhart - to play with today's question. Bringing the science we have acoustic engineer and saxophone player Trevor Cox. Plus...

May 13, 201928 min

A sense of time

Our senses create the world we experience. But do animals have a ‘sense’ of time, and does that differ between species, or between us and other animals? We know that animal senses reveal a wealth of information that humans can't access. Birds can see in ultra violet, and some fish can 'feel' electricity. So perhaps their sense of time is similar. If you've ever tried to swat flies, you'll know that they seem to have super-powered reactions that let them escape before you can blink. Presenter Geo...

May 06, 201926 min

Cat Hobaiter on communication in apes

Dr Catherine Hobaiter studies how apes communicate with each other. Although she is based at the University of St Andrews in Scotland, she spends a lot of her time in the forests of Uganda, at the Budongo Research Centre. There, she is endlessly fascinated by the behaviour of great apes. Cat Hobaiter tells Jim al-Khalili about the difficulties of carrying out research on chimps in the wild. It can take years to win the trust of the apes. She says that her approach is to adopt the attitude of a m...

Apr 29, 201927 min

Carlo Rovelli on rethinking the nature of time

Carlo Rovelli is a theoretical physicist who became a household name when his book Seven Brief Lessons on Physics became an unexpected international bestseller. His concise, and poetic, introduction to the laws and beauty of physics has sold more than a million copies. He’s also a pioneer of one of the most exciting and profound ideas in modern physics, called loop quantum gravity. Carlo Rovelli tells Jim al-Khalili how he first became interested in the nature of time when he took LSD as a young...

Apr 22, 201927 min

Corinne Le Quéré on carbon and climate

Professor Corinne Le Quéré of University of East Anglia talks to Jim Al-Khalili about tracing global carbon. Throughout the history of planet Earth, the element carbon has cycled between the atmosphere, the oceans and the biosphere. This natural cycle has maintained the amount of carbon dioxide in the atmosphere and has allowed life to exist for billions of years. Corinne Le Quéré is a climate scientist who keeps track of where the carbon comes from and where it goes – all on a truly global scal...

Apr 15, 201926 min

Ken Gabriel on why your smartphone is smart

Jim Al-Khalili talks to Ken Gabriel, the engineer responsible for popularising many of the micro devices found in smartphones and computers. Ken explains how he was inspired by what he could do with a stick and a piece of string. This led to an engineering adventure taking in spacecraft, military guidance systems and the micro-mechanical devices we use every day in our computers and smartphones. Ken Gabriel now heads up a large non-profit engineering company, Draper, which cut its teeth building...

Apr 08, 201926 min

Donna Strickland and extremely powerful lasers

Donna Strickland tells Jim Al-Khalili why she wanted to work with lasers and what it feels like to be the first woman to win a Nobel Prize for Physics in 55 years. When the first laser was built in 1960, it was an invention looking for an application. Science fiction found uses for these phenomenally powerful beams of light long before real world applications were developed. Think Star Wars light sabres and people being sliced in half. Today lasers are used for everything from hair removal to st...

Apr 01, 201926 min

Unbottling the past

Imagine finding a notebook containing the secret recipes of some of the world’s most iconic perfumes? Formulas normally kept under lock and key. That’s what happened to medical research scientist and trained chemist Andrew Holding. His grandfather Charles “Rex” Holding had been Chief Perfumer at the Bourjois Chanel factory in Croydon, near London, during the 1960s. After his death, he left behind a lifetime of perfume memorabilia; bottles of Chanel perfume, rare ingredients, fragrant soaps, and ...

Mar 25, 201930 min

California burning

When Paradise burned down last year, it made the Camp Fire the most destructive and deadly in Californian history. A few months earlier the nearby Ranch Fire was the largest. In southern California, a series of chaparral fires have brought danger to towns along the state’s coast. And the statistics show that large, dangerous fires have been increasing for decades. But the reasons are not simple. Roland Pease meets some of the experts trying to work out what is to be done. Producer: Roland Pease ...

Mar 18, 201926 min

ShakeAlertLA - California’s earthquake early warning system

Los Angeles is a city of Angels, and of earthquakes. Deadly earthquakes in 1933, 1971 and 1994 have also made it a pioneer in earthquake protection – for example with tough engineering standards to save buildings. Since 2013, with the help of scientists at the US Geological Survey, the city has been developing a resilience plan which culminated in the release of an app that should give residents precious seconds of warning when an earthquake starts. Roland Pease meets the scientists, the Mayor a...

Mar 11, 201928 min

From the Cold War to the present day

For more than 100 years chemical weapons have terrorised, maimed and killed soldiers and civilians alike. As a chemist, the part his profession has played in the development of these weapons has long concerned Andrea Sella, professor of chemistry at University College London. In this programme he examines the motivation of chemists like Dr Fritz Haber, who first encouraged the German military to deploy chlorine gas in World War One for the sake of “The Fatherland” and of Dr Gerhard Schrader, who...

Mar 04, 201928 min

From the Crimean War to the end of World War Two

In the first of two programmes he looks back to the first attempts to ban the use of chemical weapons at the end of the 19th century. Heavily defeated in the Crimea, Russia succeeded in getting unanimous agreement at the 1899 Hague Convention that poison and poison weapons should be banned from warfare. But chemicals such as chlorine, phosgene and mustard gas were heavily used in the First World War by both sides. More substances were developed in the 1930s and 1940s but weren’t used in the batt...

Feb 25, 201928 min

Tracks across time

In a dry creek bed in the middle of the Australian outback is a palaeontological prize like no other: 95-million-year-old footprints stamped in a sandstone slab by three species of dinosaur. One of the beasts was a massive, lumbering sauropod that measured 18 metres from nose to tail. But the precious trackway is in danger of being damaged by the next floods, so must be moved. In the final episode of the four-part series The Chase, science journalist Belinda Smith from the ABC in Australia disco...

Feb 18, 201927 min

Trouble in paradise

The atoll of Tetiaro is a string of tiny islands in French Polynesia, about 60km away from Tahiti. The islands – known as ‘motus’ to local Polynesians – are unique ecosystems that are crucial nesting sites for native seabirds. But invasive species threaten to disrupt these fragile environments – a fate seen across many islands in the Pacific. Rats arrived with early human settlers and have driven bird species off some of the islands. Meanwhile introduced mosquitoes have thrived in the warm condi...

Feb 11, 201926 min

Back from the Dead

The Night Parrot was supposed to be extinct and became a legend among birdwatchers in Australia: a fat, dumpy, green parrot that lived in the desert and came out at night. The last bird seen alive was promptly shot dead in 1912. Over 90 years later, a decapitated Night Parrot was found beside a fence in outback Australia, and the hunt for a living bird was on. Ornithologists descended onto the arid plains of Australia’s vast arid interior, but it took another seven years for a single photograph ...

Feb 04, 201928 min

Eye in the Sky

On this mission, SOFIA is setting out to study Titan, Saturn’s biggest moon, by flying into the faint shadow that it casts as it blocks the light from a faraway star. It’s a phenomenon called an occultation, and if the mission succeeds, it will reveal new details about Titan’s atmosphere. SOFIA is a very unusual observatory. It is a 747 aircraft with a hatch in the side, which opens in flight to reveal a large, custom-built telescope – carefully engineered to work inside a moving jet plane. Its ...

Jan 28, 201926 min

Kepler's Snowflake

The Six Cornered Snowflake, a booklet written by Johannes Kepler as a New Year's gift, sought to explain the intricate and symmetrical shape of winter's tiny stars of snow. His insightful speculations about minerals and geometry were the beginning of the modern understanding of crystals. Philip Ball tells the story of how Kepler became a key figure in the scientific revolution of the 17th Century. He was a precocious mathematician who became an adviser to Emperor Rudolf II in 1600. Although he c...

Jan 14, 201926 min

Lucretius, Sheep and Atoms

2000 years ago Lucretius composed a long poem that theorised about atoms and the natural world. Written in the first century BCE, during a chaotic and frightening time when the Roman Republic was collapsing, Lucretius encouraged people to feel free through contemplating the physics of the Universe. He said that despite living through a time of bloody civil wars and dictatorship people should not believe they were sheep who had to follow those in power. Naomi discovers that the poem is an epic, b...

Jan 07, 201926 min

Eddington's eclipse and Einstein's celebrity

Philip Ball's tale is of a solar eclipse 100 years ago observed by Arthur Eddington, a British astronomer who travelled to the remote island of Principe off the coast of West Africa and saw the stars shift in the heavens. His observations supplied the crucial proof of a theory that transformed our notions of the cosmos and turned a German physicist named Albert Einstein into an international celebrity. But this is also a tale of how a Quaker tried to use science to unite countries. The reparatio...

Dec 31, 201826 min

Earthrise

On Christmas Eve in 1968 Bill Anders was in orbit around the moon in Apollo 8 when he took one of the most iconic photos of the last fifty years: Earthrise. The image got to be seen everywhere, from a stamp issued in 1969 to commemorate the success of Apollo 8, to posters that are still available today. Gaia Vince explores the impact of this image on the environmental movement and our understanding of our place in the universe. “Oh my God. Look at that picture over there. Here’s the earth coming...

Dec 24, 201828 min

The Supercalculators

Alex Bellos is brilliant at all things mathematical, but even he can't hold a candle to the amazing mathematical feats of the supercalculators. Alex heads to Wolfsburg in Germany to meet the contestants at this year's Mental Calculation World Cup. These men and women are the fastest human number crunchers on the planet, able to multiply and divide large numbers with no need to reach for a smart phone, computer or calculator. So how do they do it, and is it a skill that any of us can learn? Alex ...

Dec 17, 201826 min

The China Syndrome

Plastic waste and pollution have become a global problem but is there any sign of a global solution? And how did we allow this to happen in the first place? Materials scientist and broadcaster, Professor Mark Miodownik, explores how we fell in love with plastic, why we've ended up with oceans of waste blighting the environment and what science and society can do about it. Programme Three: Roland Pease hears from Kenya where one of the most stringent bans on plastic bags has been in force for nea...

Dec 10, 201829 min

How Much Plastic Can We Recycle?

Plastics are fantastically versatile materials that have changed our lives. It is what we do with them, when we no longer want them, that has resulted in the global plastic crisis. Mark Miodownik explores our love hate relationship with plastics. Programme Two: Things begin to go stale Plastic waste has been a global crisis waiting to happen. To date it's estimated that around 8.3 billion tonnes of waste plastic exists. That's 25 Empire State Buildings or 1 billion elephants. Incredibly around h...

Dec 03, 201826 min

Why We Fell In Love with Plastic

Plastic waste and pollution have become a global problem but is there any sign of a global solution? And how did we allow this to happen in the first place? Materials scientist and broadcaster, Professor Mark Miodownik, explores how we fell in love with plastic, why we've ended up with oceans of waste blighting the environment and what science and society can do about it. Programme One: First Flush of Love We may not be on speaking terms right now. But we do have a love affair with plastic, in f...

Nov 26, 201826 min

Finding the Coelacanths

The first Coelacanth was discovered by a woman in South Africa in 1938. The find, by the young museum curator, was the fish equivalent of discovering a T- Rex on the Serengeti, it took the Zoological world by storm. Presenter Adam Hart tells the story of this discovery, and the steps taken by Coelacanth biologists in the decades since to find more fish, in other populations, and record them for science. Adam hears personal accounts from a deep diver who swam with Coelacanths, Eve Marshall, conse...

Nov 19, 201826 min

The Big Bang and Jet Streams

Evidence for the big bang was initially thought to be a mistake in the recording. Jet streams in the upper atmosphere were revealed by the dust emitted by Krakatoa and a collection of interested citizen scientists. In the second three episodes about the genius of accidents in science, presenter Adam Hart explores two stories of unexpected observations. Sometimes accidental discoveries are bigger than you might expect. Picture: Moonlit Coast, Credit: shaunl/Getty Images

Nov 12, 201826 min