Have you ever pondered the fact that the universe is expanding? And not only that, it's expanding at an increasing speed - meaning everything around us is getting further and further away?

If that isolating thought makes you feel slightly panicked, don't worry: this programme also contains wine!

Brian Schmidt is a Distinguished Professor of Astrophysics at the Australian National University, known for his work on supernovae: massive explosions that take place when stars come to the ends of their lives. They are among the most energetic events in the universe and incredibly difficult to find; but that’s what his High-Z Supernova Search Team did, identifying enough of these rare and distant explosions to measure just how fast they were moving away from us.

This led them to the realisation that, contrary to long-held belief in cosmology, the expansion of the universe was speeding up; a discovery which earned Brian a share of the 2011 Nobel Prize for Physics. As if that wasn't enough, he's gone on to discover one of the earliest stars in the universe; run a university; and become a winemaker, at his very own vineyard just outside Canberra.

In a conversation spanning the genius phraseology of writer Douglas Adams, the importance of pisco sours, and the similarities between astronomy and viticulture, Brian tells Professor Jim Al-Khalili how his supernovae breakthrough paved the way for a revolution in astronomy - and where the field needs to go next...

Presented by Jim Al-Khalili

The celebrated primatologist Jane Goodall died last week at the age of 91. In tribute, we’re re-sharing this interview from 2020, where she reflects on the years she spent living with the wild chimpanzees in Gombe in eastern Tanzania and why she believes the best way to bring about change is to ‘creep into people’s hearts’.

Jane shot to fame when she appeared on the cover of National Geographic magazine in 1963 and appeared in a documentary film directed by Orson Welles. Her ground breaking observations introduced us to the social and emotional lives of wild chimpanzees and changed our view of what it is to be human. Images of her younger self play-wrestling with baby chimps make Jane feel slightly apprehensive now but at the time she didn’t give it a second thought. However, she did take care to protect her young son. Seeing distressing footage of chimps who were living in captivity, she gave up fieldwork to become an activist, working to liberate chimpanzees that were being used for medical research or sold for meat or as pets, and setting up chimp sanctuaries for animals that were no longer able to live in the wild. For the last thirty years, she has campaigned gently but relentlessly to protect wild animals and wild places, touring the world and performing on stage in front of huge audiences. Her global youth programme, Roots and Shoots has inspired and empowered millions of people to understand and respect nature, leading some to call her ‘the mother Theresa of the environment’. A label she dislikes.

Producer: Anna Buckley

How much information can you extract from a burnt fragment of human bone?

Quite a lot, it turns out - not only about the individual, but also their broader lives and communities; and these are the stories unearthed by Jacqueline McKinley, a Principal Osteoarchaeologist with Wessex Archaeology.

During her career, Jackie has analysed thousands of ancient burial sites across the British Isles, bringing to life the old traditions around death via often cremated human remains. She's also assisted criminal investigators with forensic analysis, and contributed to some of the UK's best-loved archaeological TV shows.

In conversation with Professor Jim Al-Khalili, Jackie talks about the stories we can derive from skeletal remains, how western attitudes to death have gone through a major recent shift, and why she's kept some of her late father's bones.

Presented by Jim Al-Khalili

Surgeons often have to deal with the consequences of violent attacks - becoming all too familiar with patterns of public violence, and peaks around weekends, alcohol-infused events and occasions that bring together groups with conflicting ideals.

Professor Jonathan Shepherd not only recognised the link between public violence and emergency hospital admissions, he actually did something about it.

As a senior lecturer in Oral and Maxillofacial Surgery in the early 1980s, Jonathan started looking into this trend - and his research revealed that most violent assaults resulting in emergency hospital treatment are not reported to police.

As a result, he devised the ‘Cardiff Model for Violence Prevention’: a programme where hospitals share data about admissions relating to violent attacks with local authorities. He also went on to study various aspects of violent assault and deliver evidence-based solutions - from alcohol restrictions in hotspots, to less breakable beer glasses in pubs.

The impacts have been significant, delivering reductions in hospital admissions and in violent attacks recorded by police; not only in Cardiff, but in cities around the world where the model is used. Today, as an Emeritus Professor of Oral and Maxillofacial Surgery at Cardiff University - where he’s also Director of their Crime, Security and Intelligence Innovation Institute - Jonathan continues to bring together the medical sector with local authorities, finding practical ways to make cities and their residents safer.

But his career, straddling the worlds of practise, science and policy, is an unusual one; here he talks to Professor Jim Al-Khalili about what drove him to make a difference.

Presentedby Jim Al-Khalili

Doyne Farmer is something of a rebel. Back in the seventies, when he was a student, he walked into a casino in Las Vegas, sat down at a roulette table and beat the house. To anyone watching the wheel spin and the ball clatter to its final resting place, his choice of number would’ve looked like a lucky guess. But knowing the physics of the game and armed with the world’s first wearable computer, which he’d designed, a seemingly random win was actually somewhat predictable.

Doyne is an American scientist and entrepreneur who pioneered many of the fields that define the scientific agenda of our time, from chaos theory and complex systems to wearable computing. He uses big data and evermore powerful computers to apply complex systems science to the economy, to better predict our future. Much like roulette, economics can appear random but, with the right tools and understanding, it is anything but.

Now Director of the Complexity Economics Programme at the Institute for New Economic Thinking at Oxford, Doyne says there’s a real need to act, to use these powers of prediction to help resolve one of the most pressing questions of our time - how best to prevent climate change.

Presented by Jim Al-Khalili

Elephants are the largest living land mammal and today our planet is home to three species: the African bush elephant, the African forest elephant, and the Asian elephant.

But a hundred thousand years ago, in the chilly depths of the Ice Age, multiple species of elephant roamed the earth: from dog-sized dwarf elephants to towering woolly mammoths.

These gentle giants' evolutionary story and its parallels with that of humankind has long fascinated Dr Tori Herridge, a senior lecturer in evolutionary biology at the University of Sheffield, where - as a seasoned science broadcaster - she's also responsible for their Masters course in Science Communication.

Tori has spent much of her life studying fossil elephants and the sites where they were excavated; trying to establish facts behind relics that are far beyond the reach of Radio Carbon Dating. To date she's discovered dwarf mammoths on Mediterranean islands, retraced the groundbreaking Greek expedition of a female palaeontologist in the early 1900s, and even held an ancient woolly mammoth’s liver. (Verdict: stinky.)

But as she tells Professor Jim Al-Khalili, this passion for fossil-hunting is not just about understanding the past: this information is what will help us protect present-day elephants and the world around them for future generations.

Presented by Jim Al-Khalili

What does it take to earn the nickname, ‘The Leonardo da Vinci of heart surgery’?

That's the moniker given to today's guest - a man who pioneered high-profile and often controversial procedures, but also helped drive huge medical progress; carrying out around 2,000 heart transplants and 400 dual heart-lung transplants during his 60-year career.

Sir Magdi Yacoub is Emeritus Professor of Cardiothoracic Surgery at Imperial College London, and Director of Research at Harefield Hospital’s Magdi Yacoub Institute.

But it hasn't always been plain sailing. At times, his work – such as early, unsuccessful transplant attempts, or using a baboon as a life-support system for a baby – attracted serious public criticism.

Speaking to Professor Jim Al-Khalili, Sir Magdi reflects on the highs and lows of his cardio career, and offers his advice to the next generation of surgeons and researchers hoping to make their mark in heart medicine.

Presented by Jim Al-Khalili

Claudia de Rham has rather an unusual relationship with gravity.

While she has spent her career exploring its fundamental nature, much of her free time has involved trying to defy it - from scuba diving in the Indian Ocean to piloting small aircraft over the Canadian waterfalls. Her ultimate ambition was to escape gravity’s clutches altogether and become an astronaut, a dream that was snatched away by an unlikely twist of fate.

However, Claudia has no regrets - and says defying gravity for much of her life has helped her to truly understand it.

As Professor of theoretical physics at Imperial College London, she now grapples with deep mathematics, where the fields of particle physics, gravity and cosmology intersect, on a quest to understand how the universe really works. She is a pioneer of the theory of massive gravity, a theory which could take us beyond even Einstein’s theory of relativity and shed light on why the universe is expanding at an ever-increasing rate.

Presented by Jim Al-Khalili

When you think of Artificial Intelligence, does it inspire confidence, or concern?

Although it's now generally accepted that this technology will play a major role in our future, a lot of conversations around AI and machine learning come back to the argument over us losing control and robots taking over.

Happily, Neil Lawrence has a more optimistic view of the power of AI, and how we might navigate the potential pitfalls. Neil is the DeepMind Professor of Machine Learning at the University of Cambridge, and over the course of his career has been involved in deploying AI and machine learning in both academic and commercial scenarios, with a stint at Amazon as well as working across fields as varied as movie animation, Formula 1 strategy, and medical research.

Speaking with Professor Jim Al-Khalili, Neil says ultimately his efforts are all about making a difference to our everyday lives - and that we need to learn how to embrace AI, albeit with a healthy dollop of scepticism; not least when it comes to how our data is used, and the power of 'the digital oligarchy'...

Presented by Jim Al-Khalili

A frozen, white world at the far-reaches of the globe, where you're surrounded by snow and silence, might sound rather appealing. Factor in temperatures that drop to -57°C and a few of us might be put off - but for glaciologist Liz Morris, that's very much her happy place.

Liz is an Emeritus Associate at the University of Cambridge’s Scott Polar Research Institute, and was among the first British women scientists to work on the planet’s coldest continent, Antarctica. Over the course of her career, Liz has gathered vital data on polar ice sheets and how they’re affected by climate change. She's also made numerous research trips across the Greenland Ice Shelf, and has a glacier named after her in Antarctica.

In conversation with Professor Jim Al-Khalili, Liz discusses her fascination with glaciers and ice - and explains her unwavering determination to break into what was once a heavily male-dominated field.

Presented by Jim Al-Khalili