Melvyn Bragg and guests discuss the tantalising idea that there are shortcuts between distant galaxies, somewhere out there in the universe. The idea emerged in the context of Einstein's theories and the challenge has been not so much to prove their unlikely existence as to show why they ought to be impossible. The universe would have to folded back on itself in places, and there would have to be something to make the wormholes and then to keep them open. But is there anywhere in the vast universe like that? Could there be holes that we or more advanced civilisations might travel through, from one galaxy to another and, if not, why not?

With

Toby Wiseman Professor of Theoretical Physics at Imperial College London

Katy Clough Senior Lecturer in Mathematics at Queen Mary, University of London

And

Andrew Pontzen Professor of Cosmology at Durham University

Producer: Simon Tillotson

Reading list:

Jim Al-Khalili, Black Holes, Wormholes and Time Machines (Taylor & Francis, 1999)

Andrew Pontzen, The Universe in a Box: Simulations and the Quest to Code the Cosmos (Riverhead Books, 2023)

Claudia de Rham, The Beauty of Falling: A Life in Pursuit of Gravity (Princeton University Press, 2024)

Carl Sagan, Contact (Simon and Schuster, 1985)

Kip Thorne, Black Holes & Time Warps: Einstein's Outrageous Legacy (W. W. Norton & Company, 1994)

Kip Thorne, Science of Interstellar (W. W. Norton & Company, 2014)

Matt Visser, Lorentzian Wormholes: From Einstein to Hawking (American Institute of Physics Melville, NY, 1996)

In Our Time is a BBC Studios Audio Production

Melvyn Bragg and guests discuss the most abundant lifeform on Earth: the viruses that 'eat' bacteria. Early in the 20th century, scientists noticed that something in their Petri dishes was making bacteria disappear and they called these bacteriophages, things that eat bacteria. From studying these phages, it soon became clear that they offered countless real or potential benefits for understanding our world, from the tracking of diseases to helping unlock the secrets of DNA to treatments for long term bacterial infections. With further research, they could be an answer to the growing problem of antibiotic resistance.

With

Martha Clokie Director for the Centre for Phage Research and Professor of Microbiology at the University of Leicester

James Ebdon Professor of Environmental Microbiology at the University of Brighton

And

Claas Kirchhelle Historian and Chargé de Recherche at the French National Institute of Health and Medical Research’s CERMES3 Unit in Paris.

Producer: Simon Tillotson

In Our Time is a BBC Studios Audio Production

Reading list:

James Ebdon, ‘Tackling sources of contamination in water: The age of phage’ (Microbiologist, Society for Applied Microbiology, Vol 20.1, 2022)

Thomas Häusler, Viruses vs. Superbugs: A Solution to the Antibiotics Crisis? (Palgrave Macmillan, 2006)

Tom Ireland, The Good Virus: The Untold Story of Phages: The Mysterious Microbes that Rule Our World, Shape Our Health and Can Save Our Future (Hodder Press, 2024)

Claas Kirchhelle and Charlotte Kirchhelle, ‘Northern Normal–Laboratory Networks, Microbial Culture Collections, and Taxonomies of Power (1939-2000)’ (SocArXiv Papers, 2024)

Dmitriy Myelnikov, ‘An alternative cure: the adoption and survival of bacteriophage therapy in the USSR, 1922–1955’ (Journal of the History of Medicine and Allied Sciences 73, no. 4, 2018)

Forest Rohwer, Merry Youle, Heather Maughan and Nao Hisakawa, Life in our Phage World: A Centennial Field Guide to Earth’s most Diverse Inhabitants (Wholon, 2014)

Steffanie Strathdee and Thomas Patterson (2019) The Perfect Predator: A Scientist’s Race to Save Her Husband from a Deadly Superbug: A Memoir (Hachette Books, 2020)

William C. Summers, Félix d`Herelle and the Origins of Molecular Biology (Yale University Press, 1999)

William C. Summers, The American Phage Group: Founders of Molecular Biology (University Press, 2023)

Melvyn Bragg and guests discuss the planet which is closest to our Sun. We see it as an evening or a morning star, close to where the Sun has just set or is about to rise, and observations of Mercury helped Copernicus understand that Earth and the other planets orbit the Sun, so displacing Earth from the centre of our system. In the 20th century, further observations of Mercury helped Einstein prove his general theory of relativity. For the last 50 years we have been sending missions there to reveal something of Mercury's secrets and how those relate to the wider universe, and he latest, BepiColombo, is out there in space now.

With

Emma Bunce Professor of Planetary Plasma Physics and Director of the Institute for Space at the University of Leicester

David Rothery Professor of Planetary Geosciences at the Open University

And

Carolin Crawford Emeritus Fellow of Emmanuel College, University of Cambridge, and Emeritus Member of the Institute of Astronomy, Cambridge

Producer: Simon Tillotson In Our Time is a BBC Studios Audio production

Reading list:

Emma Bunce, ‘All (X-ray) eyes on Mercury’ (Astronomy & Geophysics, Volume 64, Issue 4, August 2023)

Emma Bunce et al, ‘The BepiColombo Mercury Imaging X-Ray Spectrometer: Science Goals, Instrument Performance and Operations’ (Space Science Reviews: SpringerLink, volume 216, article number 126, Nov 2020)

David A. Rothery, Planet Mercury: From Pale Pink Dot to Dynamic World (Springer, 2014)

Melvyn Bragg and guests discuss the Serbian-American inventor Nikola Tesla (1856-1943) and his role in the development of electrical systems towards the end of the nineteenth century. He made his name in New York in the contest over which current should flow into homes and factories in America. Some such as Edison backed direct current or DC while others such as Westinghouse backed alternating current or AC and Nikola Tesla’s invention of a motor that worked on AC swung it for the alternating system that went on to power the modern age. He ensured his reputation and ideas burnt brightly for the next decades, making him synonymous with the lone, genius inventor of the new science fiction.

With

Simon Schaffer Emeritus Fellow of Darwin College, University of Cambridge

Jill Jonnes Historian and author of “Empires of Light: Edison, Tesla, Westinghouse and the Race to Electrify the World”

And

Iwan Morus Professor of History at Aberystwyth University

Producer: Simon Tillotson

Reading list:

W. Bernard Carlson, Tesla: Inventor of the Electrical Age (Princeton University Press, 2013)

Margaret Cheney and Robert Uth, Tesla: Master of Lightning (Barnes & Noble Books, 1999)

Thomas P. Hughes, Networks of Power: Electrification in Western Society, 1880-1930 (Johns Hopkins University Press, 1983)

Carolyn Marvin, When Old Technologies Were New (Open University Press, 1988)

Iwan Rhys Morus, Nikola Tesla and the Electrical Future (Icon Books, 2019)

Iwan Rhys Morus, How The Victorians Took Us To The Moon (Icon, 2022)

David E. Nye, Electrifying America: Social Meanings of a New Technology (MIT Press, 1991)

John J. O’Neill, Prodigal Genius: The Life of Nikola Tesla (first published 1944; Cosimo Classics, 2006)

Marc J. Seifer, Wizard: The Life and Times of Nikola Tesla, Biography of a Genius (first published 1996; Citadel Press, 2016)

Nikola Tesla, My Inventions: The Autobiography of Nikola Tesla (first published 1919; Martino Fine Books, 2011)

Nikola Tesla, My Inventions and other Writings (Penguin, 2012)

In Our Time is a BBC Studios Audio production

Melvyn Bragg and guests discuss the German physicist who, at the age of 23 and while still a student, effectively created quantum mechanics for which he later won the Nobel Prize. Werner Heisenberg made this breakthrough in a paper in 1925 when, rather than starting with an idea of where atomic particles were at any one time, he worked backwards from what he observed of atoms and their particles and the light they emitted, doing away with the idea of their continuous orbit of the nucleus and replacing this with equations. This was momentous and from this flowed what’s known as his Uncertainty Principle, the idea that, for example, you can accurately measure the position of an atomic particle or its momentum, but not both.

With

Fay Dowker Professor of Theoretical Physics at Imperial College London

Harry Cliff Research Fellow in Particle Physics at the University of Cambridge

And

Frank Close Professor Emeritus of Theoretical Physics and Fellow Emeritus at Exeter College at the University of Oxford

Producer: Simon Tillotson

Reading list:

Philip Ball, Beyond Weird: Why Everything You Thought You Knew about Quantum Physics Is Different (Vintage, 2018)

John Bell, ‘Against 'measurement'’ (Physics World, Vol 3, No 8, 1990)

Mara Beller, Quantum Dialogue: The Making of a Revolution (University of Chicago Press, 2001)

David C. Cassidy, Beyond Uncertainty: Heisenberg, Quantum Physics, And The Bomb (Bellevue Literary Press, 2010)

Werner Heisenberg, Physics and Philosophy (first published 1958; Penguin Classics, 2000)

Carlo Rovelli, Helgoland: The Strange and Beautiful Story of Quantum Physics (Penguin, 2022)

Melvyn Bragg and guests discuss some of the chemical signals coursing through our bodies throughout our lives, produced in separate areas and spreading via the bloodstream. We call these 'hormones' and we produce more than 80 of them of which the best known are arguably oestrogen, testosterone, adrenalin, insulin and cortisol. On the whole hormones operate without us being immediately conscious of them as their goal is homeostasis, maintaining the levels of everything in the body as required without us having to think about them first. Their actions are vital for our health and wellbeing and influence many different aspects of the way our bodies work.

With

Sadaf Farooqi Professor of Metabolism and Medicine at the University of Cambridge

Rebecca Reynolds Professor of Metabolic Medicine at the University of Edinburgh

And

Andrew Bicknell Associate Professor in the School of Biological Sciences at the University of Reading

Produced by Victoria Brignell

Reading list:

Rachel Carson, Silent Spring (first published 1962; Penguin Classics, 2000)

Stephen Nussey and Saffron Whitehead, Endocrinology: An Integrated Approach (BIOS Scientific Publishers; 2001)

Aylinr Y. Yilmaz, Comprehensive Introduction to Endocrinology for Novices (Independently published, 2023)

Melvyn Bragg and guests discuss the tiny drifting organisms in the oceans that sustain the food chain for all the lifeforms in the water and so for the billions of people who, in turn, depend on the seas for their diet. In Earth's development, the plant-like ones among them, the phytoplankton, produced so much oxygen through photosynthesis that around half the oxygen we breathe today originated there. And each day as the sun rises, the animal ones, the zooplankton, sink to the depths of the seas to avoid predators in such density that they appear on ship sonars like a new seabed, only to rise again at night in the largest migration of life on this planet.

With

Carol Robinson Professor of Marine Sciences at the University of East Anglia

Abigail McQuatters-Gollop Associate Professor of Marine Conservation at the University of Plymouth

And

Christopher Lowe Lecturer in Marine Biology at Swansea University

Producer: Simon Tillotson

Reading list:

Juli Berwald, Spineless: The Science of Jellyfish and the Art of Growing a Backbone (Riverhead Books, 2018)

Sir Alister Hardy, The Open Sea: The World of Plankton (first published 1959; Collins New Naturalist Library, 2009)

Richard Kirby, Ocean Drifters: A Secret World Beneath the Waves (Studio Cactus Ltd, 2010)

Robert Kunzig, Mapping the Deep: The Extraordinary Story of Ocean Science (Sort Of Books, 2000)

Christian Sardet, Plankton: Wonders of the Drifting World (University of Chicago Press, 2015)

Helen Scales, The Brilliant Abyss: True Tales of Exploring the Deep Sea, Discovering Hidden Life and Selling the Seabed (Bloomsbury Sigma, 2022)

Melvyn Bragg and guests discuss the man who, in 1905, produced several papers that were to change the world of physics and whose name went on to become a byword for genius. This was Albert Einstein, then still a technical expert at a Swiss patent office, and that year of 1905 became known as his annus mirabilis ('miraculous year'). While Einstein came from outside the academic world, some such as Max Planck championed his theory of special relativity, his principle of mass-energy equivalence that followed, and his explanations of Brownian Motion and the photoelectric effect. Yet it was not until 1919, when a solar eclipse proved his theory that gravity would bend light, that Einstein became an international celebrity and developed into an almost mythical figure.

With

Richard Staley Professor in History and Philosophy of Science at the University of Cambridge and Professor in History of Science at the University of Copenhagen

Diana Kormos Buchwald Robert M. Abbey Professor of History and Director and General Editor of The Einstein Papers Project at the California Institute of Technology

And

John Heilbron Professor Emeritus at the University of California, Berkeley

Producer: Simon Tillotson

Reading list:

Ronald W. Clark, Einstein: The Life and Times (first published 1971; HarperPaperbacks, 2011)

Albert Einstein (eds. Jurgen Renn and Hanoch Gutfreund), Relativity: The Special and the General Theory - 100th Anniversary Edition (Princeton University Press, 2019)

Albert Einstein, Out of My Later Years (first published 1950; Citadel Press, 1974)

Albert Einstein (ed. Paul A. Schilpp), Albert Einstein: Philosopher-Scientist: The Library of Living Philosophers Volume VII (first published 1949; Open Court, 1970)

Albert Einstein (eds. Otto Nathan and Heinz Norden), Einstein on Peace (first published 1981; Literary Licensing, 2011)

Albrecht Folsing, Albert Einstein: A Biography (Viking, 1997)

J. L. Heilbron, Niels Bohr: A Very Short Introduction (Oxford University Press, 2020)

Walter Isaacson, Einstein: His Life and Universe (Simon & Schuster, 2008)

Max Jammer, Einstein and Religion (Princeton University Press, 2002)

Michel Janssen and Christoph Lehner (eds.), The Cambridge Companion to Einstein (Cambridge University Press, 2014)

Dennis Overbye, Einstein in Love: A Scientific Romance (Viking, 2000)

Abraham Pais, Subtle Is the Lord: The Science and the Life of Albert Einstein (Oxford University Press, 1982)

David E. Rowe and Robert Schulmann (eds.), Einstein on Politics: His Private Thoughts and Public Stands on Nationalism, Zionism, War, Peace, and the Bomb (Princeton University Press, 2007)

Matthew Stanley, Einstein's War: How Relativity Triumphed Amid the Vicious Nationalism of World War I (Dutton, 2019)

Fritz Stern, Einstein’s German World (Princeton University Press, 1999)

A. Douglas Stone, Einstein and the Quantum: The Quest of the Valiant Swabian (Princeton University Press, 2013)

Milena Wazeck (trans. Geoffrey S. Koby), Einstein's Opponents: The Public Controversy About the Theory of Relativity in the 1920s (Cambridge University Press, 2014)

Jupiter is the largest planet in our solar system, and it’s hard to imagine a world more alien and different from Earth. It’s known as a Gas Giant, and its diameter is eleven times the size of Earth’s: our planet would fit inside it one thousand three hundred times. But its mass is only three hundred and twenty times greater, suggesting that although Jupiter is much bigger than Earth, the stuff it’s made of is much, much lighter. When you look at it through a powerful telescope you see a mass of colourful bands and stripes: these are the tops of ferocious weather systems that tear around the planet, including the great Red Spot, probably the longest-lasting storm in the solar system. Jupiter is so enormous that it’s thought to have played an essential role in the distribution of matter as the solar system formed – and it plays an important role in hoovering up astral debris that might otherwise rain down on Earth. It’s almost a mini solar system in its own right, with 95 moons orbiting around it. At least two of these are places life might possibly be found.

With

Michele Dougherty, Professor of Space Physics and Head of the Department of Physics at Imperial College London, and principle investigator of the magnetometer instrument on the JUICE spacecraft (JUICE is the Jupiter Icy Moons Explorer, a mission launched by the European Space Agency in April 2023)

Leigh Fletcher, Professor of Planetary Science at the University of Leicester, and interdisciplinary scientist for JUICE

Carolin Crawford, Emeritus Fellow of Emmanuel College, University of Cambridge, and Emeritus Member of the Institute of Astronomy, Cambridge

Melvyn Bragg and guests discuss the power-packs within cells in all complex life on Earth.

Inside each cell of every complex organism there are structures known as mitochondria. The 19th century scientists who first observed them thought they were bacteria which had somehow invaded the cells they were studying. We now understand that mitochondria take components from the food we eat and convert them into energy.

Mitochondria are essential for complex life, but as the components that run our metabolisms they can also be responsible for a range of diseases – and they probably play a role in how we age. The DNA in mitochondria is only passed down the maternal line. This means it can be used to trace population movements deep into human history, even back to an ancestor we all share: mitochondrial Eve.

With

Mike Murphy Professor of Mitochondrial Redox Biology at the University of Cambridge

Florencia Camus NERC Independent Research Fellow at University College London

and

Nick Lane Professor of Evolutionary Biochemistry at University College London

Producer Luke Mulhall

Melvyn Bragg and guests discuss the life, ideas and legacy of the pioneering Swedish botanist Carl Linnaeus (1707 – 1778). The philosopher Jean-Jacques Rousseau once wrote: "Tell him I know no greater man on earth".

The son of a parson, Linnaeus grew up in an impoverished part of Sweden but managed to gain a place at university. He went on to transform biology by making two major innovations. He devised a simpler method of naming species and he developed a new system for classifying plants and animals, a system that became known as the Linnaean hierarchy. He was also one of the first people to grow a banana in Europe.

With

Staffan Muller-Wille University Lecturer in History of Life, Human and Earth Sciences at the University of Cambridge

Stella Sandford Professor of Modern European Philosophy at Kingston University, London

and

Steve Jones Senior Research Fellow in Genetics at University College, London

Producer Luke Mulhall