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In Our Time: Science

In Our Time: Science

Scientific principles, theory, and the role of key figures in the advancement of science.

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Kinetic Theory

Melvyn Bragg and guests discuss how scientists sought to understand the properties of gases and the relationship between pressure and volume, and what that search unlocked. Newton theorised that there were static particles in gases that pushed against each other all the harder when volume decreased, hence the increase in pressure. Those who argued that molecules moved, and hit each other, were discredited until James Maxwell and Ludwig Boltzmann used statistics to support this kinetic theory. Ideas about atoms developed in tandem with this, and it came as a surprise to scientists in C20th that the molecules underpinning the theory actually existed and were not simply thought experiments. The image above is of Ludwig Boltzmann from a lithograph by Rudolf Fenzl, 1898 With Steven Bramwell Professor of Physics at University College London Isobel Falconer Reader in History of Mathematics at the University of St Andrews and Ted Forgan Emeritus Professor of Physics at the University of Birmingham Producer: Simon Tillotson
2019-05-23
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The Evolution of Teeth

Melvyn Bragg and guests discuss theories about the origins of teeth in vertebrates, and what we can learn from sharks in particular and their ancestors. Great white sharks can produce up to 100,000 teeth in their lifetimes. For humans, it is closer to a mere 50 and most of those have to last from childhood. Looking back half a billion years, though, the ancestors of sharks and humans had no teeth in their mouths at all, nor jaws. They were armoured fish, sucking in their food. The theory is that either their tooth-like scales began to appear in mouths as teeth, or some of their taste buds became harder. If we knew more about that, and why sharks can regenerate their teeth, then we might learn how humans could grow new teeth in later lives. With Gareth Fraser Assistant Professor in Biology at the University of Florida Zerina Johanson Merit Researcher in the Department of Earth Sciences at the Natural History Museum and Philip Donoghue Professor of Palaeobiology at the University of Bristol Producer: Simon Tillotson
2019-04-11
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Pheromones

Melvyn Bragg and guests discuss how members of the same species send each other invisible chemical signals to influence the way they behave. Pheromones are used by species across the animal kingdom in a variety of ways, such as laying trails to be followed, to raise the alarm, to scatter from predators, to signal dominance and to enhance attractiveness and, in honey bees, even direct development into queen or worker. The image above is of male and female ladybirds that have clustered together in response to pheromones. With Tristram Wyatt Senior Research Fellow at the Department of Zoology at the University of Oxford Jane Hurst William Prescott Professor of Animal Science at the University of Liverpool and Francis Ratnieks Professor of Apiculture and Head of the Laboratory of Apiculture and Social Insects at the University of Sussex Producer: Simon Tillotson
2019-02-21
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Aristotle's Biology

Melvyn Bragg and guests discuss the remarkable achievement of Aristotle (384-322BC) in the realm of biological investigation, for which he has been called the originator of the scientific study of life. Known mainly as a philosopher and the tutor for Alexander the Great, who reportedly sent him animal specimens from his conquests, Aristotle examined a wide range of life forms while by the Sea of Marmara and then on the island of Lesbos. Some ideas, such as the the spontaneous generation of flies, did not survive later scrutiny, yet his influence was extraordinary and his work was unequalled until the early modern period. The image above is of the egg and embryo of a dogfish, one of the animals Aristotle described accurately as he recorded their development. With Armand Leroi Professor of Evolutionary Development Biology at Imperial College London Myrto Hatzimichali Lecturer in Classics at the University of Cambridge And Sophia Connell Lecturer in Philosophy at Birkbeck, University of London Producer: Simon Tillotson
2019-02-07
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Emmy Noether

Melvyn Bragg and guests discuss the ideas and life of one of the greatest mathematicians of the 20th century, Emmy Noether. Noether?s Theorem is regarded as one of the most important mathematical theorems, influencing the evolution of modern physics. Born in 1882 in Bavaria, Noether studied mathematics at a time when women were generally denied the chance to pursue academic careers and, to get round objections, she spent four years lecturing under a male colleague?s name. In the 1930s she faced further objections to her teaching, as she was Jewish, and she left for the USA when the Nazis came to power. Her innovative ideas were to become widely recognised and she is now considered to be one of the founders of modern algebra. With Colva Roney Dougal Professor of Pure Mathematics at the University of St Andrews David Berman Professor in Theoretical Physics at Queen Mary, University of London Elizabeth Mansfield Professor of Mathematics at the University of Kent Producer: Simon Tillotson
2019-01-24
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Venus

Melvyn Bragg and guests discuss the planet Venus which is both the morning star and the evening star, rotates backwards at walking speed and has a day which is longer than its year. It has long been called Earth?s twin, yet the differences are more striking than the similarities. Once imagined covered with steaming jungles and oceans, we now know the surface of Venus is 450 degrees celsius, and the pressure there is 90 times greater than on Earth, enough to crush an astronaut. The more we learn of it, though, the more we learn of our own planet, such as whether Earth could become more like Venus in some ways, over time. With Carolin Crawford Public Astronomer at the Institute of Astronomy and Fellow of Emmanuel College, University of Cambridge Colin Wilson Senior Research Fellow in Planetary Science at the University of Oxford And Andrew Coates Professor of Physics at Mullard Space Science Laboratory, University College London Produced by: Simon Tillotson and Julia Johnson
2018-12-27
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Free Radicals

Melvyn Bragg and guests discuss the properties of atoms or molecules with a single unpaired electron, which tend to be more reactive, keen to seize an electron to make it a pair. In the atmosphere, they are linked to reactions such as rusting. Free radicals came to prominence in the 1950s with the discovery that radiation poisoning operates through free radicals, as it splits water molecules and produces a very reactive hydroxyl radical which damages DNA and other molecules in the cell. There is also an argument that free radicals are a byproduct of normal respiration and over time they cause an accumulation of damage that is effectively the process of ageing. For all their negative associations, free radicals play an important role in signalling and are also linked with driving cell division, both cancer and normal cell division, even if they tend to become damaging when there are too many of them. With Nick Lane Professor of Evolutionary Biochemistry at University College London Anna Croft Associate Professor at the Department of Chemical and Environmental Engineering at the University of Nottingham And Mike Murphy Professor of Mitochondrial Redox Biology at Cambridge University Producer: Simon Tillotson
2018-11-01
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Automata

Melvyn Bragg and guests discuss the history of real and imagined machines that appear to be living, and the questions they raise about life and creation. Even in myth they are made by humans, not born. The classical Greeks built some and designed others, but the knowledge of how to make automata and the principles behind them was lost in the Latin Christian West, remaining in the Greek-speaking and Arabic-speaking world. Western travellers to those regions struggled to explain what they saw, attributing magical powers. The advance of clockwork raised further questions about what was distinctly human, prompting Hobbes to argue that humans were sophisticated machines, an argument explored in the Enlightenment and beyond. The image above is Jacques de Vaucanson's mechanical duck (1739), which picked up grain, digested and expelled it. If it looks like a duck... with Simon Schaffer Professor of History of Science at Cambridge University Elly Truitt Associate Professor of Medieval History at Bryn Mawr College And Franziska Kohlt Doctoral Researcher in English Literature and the History of Science at the University of Oxford Producer: Simon Tillotson
2018-09-20
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Echolocation

Melvyn Bragg and guests discuss how some bats, dolphins and other animals emit sounds at high frequencies to explore their environments, rather than sight. This was such an unlikely possibility, to natural historians from C18th onwards, that discoveries were met with disbelief even into the C20th; it was assumed that bats found their way in the dark by touch. Not all bats use echolocation, but those that do have a range of frequencies for different purposes and techniques for preventing themselves becoming deafened by their own sounds. Some prey have evolved ways of detecting when bats are emitting high frequencies in their direction, and some fish have adapted to detect the sounds dolphins use to find them. With Kate Jones Professor of Ecology and Biodiversity at University College London Gareth Jones Professor of Biological Sciences at the University of Bristol And Dean Waters Lecturer in the Environment Department at the University of York Producer: Simon Tillotson.
2018-06-21
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The Proton

Melvyn Bragg and guests discuss the discovery and growing understanding of the Proton, formed from three quarks close to the Big Bang and found in the nuclei of all elements. The positive charges they emit means they attract the fundamental particles of negatively charged electrons, an attraction that leads to the creation of atoms which in turn leads to chemistry, biology and life itself. The Sun (in common with other stars) is a fusion engine that turn protons by a series of processes into helium, emitting energy in the process, with about half of the Sun's protons captured so far. Hydrogen atoms, stripped of electrons, are single protons which can be accelerated to smash other nuclei and have applications in proton therapy. Many questions remain, such as why are electrical charges for protons and electrons so perfectly balanced? With Frank Close Professor Emeritus of Physics at the University of Oxford Helen Heath Reader in Physics at the University of Bristol And Simon Jolly Lecturer in High Energy Physics at University College London Producer: Simon Tillotson.
2018-04-26
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George and Robert Stephenson

Melvyn Bragg and guests discuss the contribution of George Stephenson (1781-1848) and his son Robert (1803-59) to the development of the railways in C19th. George became known as The Father of Railways and yet arguably Robert's contribution was even greater, with his engineering work going far beyond their collaboration. Robert is credited with the main role in the design of their locomotives. George had worked on stationary colliery steam engines and, with Robert, developed the moving steam engine Locomotion No1 for the Stockton and Darlington Railway in 1825. They produced the Rocket for the Rainhill Trials on the Liverpool and Manchester Railway in 1829. From there, the success of their designs and engineering led to the expansion of railways across Britain and around the world. with Dr Michael Bailey Railway historian and editor of the most recent biography of Robert Stephenson Julia Elton Past President of the Newcomen Society for the History of Engineering and Technology and Colin Divall Professor Emeritus of Railway Studies at the University of York Producer: Simon Tillotson.
2018-04-12
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Rosalind Franklin

Melvyn Bragg and guests discuss the pioneering scientist Rosalind Franklin (1920 - 1958). During her distinguished career, Franklin carried out ground-breaking research into coal and viruses but she is perhaps best remembered for her investigations in the field of DNA. In 1952 her research generated a famous image that became known as Photograph 51. When the Cambridge scientists Francis Crick and James Watson saw this image, it enabled them the following year to work out that DNA has a double-helix structure, one of the most important discoveries of modern science. Watson, Crick and Franklin's colleague Maurice Wilkins received a Nobel Prize in 1962 for this achievement but Franklin did not and today many people believe that Franklin has not received enough recognition for her work. With: Patricia Fara President of the British Society for the History of Science Jim Naismith Interim lead of the Rosalind Franklin Institute, Director of the Research Complex at Harwell and Professor at the University of Oxford Judith Howard Professor of Chemistry at Durham University Producer: Victoria Brignell.
2018-02-22
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Fungi

Melvyn Bragg and guests discuss fungi. These organisms are not plants or animals but a kingdom of their own. Millions of species of fungi live on the Earth and they play a crucial role in ecosystems, enabling plants to obtain nutrients and causing material to decay. Without fungi, life as we know it simply would not exist. They are also a significant part of our daily life, making possible the production of bread, wine and certain antibiotics. Although fungi brought about the colonisation of the planet by plants about 450 million years ago, some species can kill humans and devastate trees. With: Lynne Boddy Professor of Fungal Ecology at Cardiff University Sarah Gurr Professor of Food Security in the Biosciences Department at the University of Exeter David Johnson N8 Chair in Microbial Ecology at the University of Manchester Producer: Victoria Brignell.
2018-02-15
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Cephalopods

The octopus, the squid, the nautilus and the cuttlefish are some of the most extraordinary creatures on this planet, intelligent and yet apparently unlike other life forms. They are cephalopods and are part of the mollusc family like snails and clams, and they have some characteristics in common with those. What sets them apart is the way members of their group can change colour, camouflage themselves, recognise people, solve problems, squirt ink, power themselves with jet propulsion and survive both on land, briefly, and in the deepest, coldest oceans. And, without bones or shells, they grow so rapidly they can outstrip their rivals when habitats change, making them the great survivors and adaptors of the animal world. With Louise Allcock Lecturer in Zoology at the National University of Ireland, Galway Paul Rodhouse Emeritus Fellow of the British Antarctic Survey and Jonathan Ablett Senior Curator of Molluscs at the Natural History Museum Producer: Simon Tillotson.
2018-02-01
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Carl Friedrich Gauss

Melvyn Bragg and guests discuss Gauss (1777-1855), widely viewed as one of the greatest mathematicians of all time. He was a child prodigy, correcting his father's accounts before he was 3, dumbfounding his teachers with the speed of his mental arithmetic, and gaining a wealthy patron who supported his education. He wrote on number theory when he was 21, with his Disquisitiones Arithmeticae, which has influenced developments since. Among his achievements, he was the first to work out how to make a 17-sided polygon, he predicted the orbit of the minor planet Ceres, rediscovering it, he found a way of sending signals along a wire, using electromagnetism, the first electromagnetic telegraph, and he advanced the understanding of parallel lines on curved surfaces. With Marcus du Sautoy Professor of Mathematics and Simonyi Professor for the Public Understanding of Science at the University of Oxford Colva Roney-Dougal Reader in Pure Mathematics at the University of St Andrews And Nick Evans Professor of Theoretical Physics at the University of Southampton Producer: Simon Tillotson.
2017-11-30
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Feathered Dinosaurs

Melvyn Bragg and guests discuss the development of theories about dinosaur feathers, following discoveries of fossils which show evidence of feathers. All dinosaurs were originally thought to be related to lizards - the word 'dinosaur' was created from the Greek for 'terrible lizard' - but that now appears false. In the last century, discoveries of fossils with feathers established that at least some dinosaurs were feathered and that some of those survived the great extinctions and evolved into the birds we see today. There are still many outstanding areas for study, such as what sorts of feathers they were, where on the body they were found, what their purpose was and which dinosaurs had them. With Mike Benton Professor of Vertebrate Palaeontology at the University of Bristol Steve Brusatte Reader and Chancellor's Fellow in Vertebrate Palaeontology at the University of Edinburgh and Maria McNamara Senior Lecturer in Geology at University College, Cork Producer: Simon Tillotson.
2017-10-26
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Bird Migration

Melvyn Bragg and guests discuss why some birds migrate and others do not, how they select their destinations and how they navigate the great distances, often over oceans. For millennia, humans set their calendars to birds' annual arrivals, and speculated about what happened when they departed, perhaps moving deep under water, or turning into fish or shellfish, or hibernating while clinging to trees upside down. Ideas about migration developed in C19th when, in Germany, a stork was noticed with an African spear in its neck, indicating where it had been over the winter and how far it had flown. Today there are many ideas about how birds use their senses of sight and smell, and magnetic fields, to find their way, and about why and how birds choose their destinations and many questions. Why do some scatter and some flock together, how much is instinctive and how much is learned, and how far do the benefits the migrating birds gain outweigh the risks they face? With Barbara Helm Reader at the Institute of Biodiversity, Animal Health and Comparative Medicine at the University of Glasgow Tim Guilford Professor of Animal Behaviour and Tutorial Fellow of Zoology at Merton College, Oxford and Richard Holland Senior Lecturer in Animal Cognition at Bangor University Producer: Simon Tillotson.
2017-07-06
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Enzymes

Melvyn Bragg and guests discuss enzymes, the proteins that control the speed of chemical reactions in living organisms. Without enzymes, these reactions would take place too slowly to keep organisms alive: with their actions as catalysts, changes which might otherwise take millions of years can happen hundreds of times a second. Some enzymes break down large molecules into smaller ones, like the ones in human intestines, while others use small molecules to build up larger, complex ones, such as those that make DNA. Enzymes also help keep cell growth under control, by regulating the time for cells to live and their time to die, and provide a way for cells to communicate with each other. With Nigel Richards Professor of Biological Chemistry at Cardiff University Sarah Barry Lecturer in Chemical Biology at King's College London And Jim Naismith Director of the Research Complex at Harwell Bishop Wardlaw Professor of Chemical Biology at the University of St Andrews Professor of Structural Biology at the University of Oxford Producer: Simon Tillotson.
2017-06-01
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Louis Pasteur

Melvyn Bragg and guests discuss the life and work of Louis Pasteur (1822-1895) and his extraordinary contribution to medicine and science. It is said few people have saved more lives than Pasteur. A chemist, he showed that otherwise identical molecules could exist as 'left' and 'right-handed' versions and that molecules produced by living things were always left-handed. He proposed a germ theory to replace the idea of spontaneous generation. He discovered that microorganisms cause fermentation and disease. He began the process named after him, pasteurisation, heating liquids to 50-60 C to kill microbes. He saved the beer and wine industries in France when they were struggling with microbial contamination. He saved the French silk industry when he found a way of protecting healthy silkworm eggs from disease. He developed vaccines against anthrax and rabies and helped establish immunology. Many of his ideas were developed further after his lifetime, but one of his legacies was a charitable body, the Pasteur Institute, to continue research into infectious disease. With Andrew Mendelsohn Reader in the School of History at Queen Mary, University of London Anne Hardy Honorary Professor at the Centre for History in Public Health at the London School of Hygiene and Tropical Medicine and Michael Worboys Emeritus Professor in the History of Science, Technology and Medicine at the University of Manchester Producer: Simon Tillotson.
2017-05-18
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Pauli's Exclusion Principle

Melvyn Bragg and guests discuss the life and ideas of Wolfgang Pauli (1900-1958), whose Exclusion Principle is one of the key ideas in quantum mechanics. A brilliant physicist, at 21 Pauli wrote a review of Einstein's theory of general relativity and that review is still a standard work of reference today. The Pauli Exclusion Principle proposes that no two electrons in an atom can be at the same time in the same state or configuration, and it helps explain a wide range of phenomena such as the electron shell structure of atoms. Pauli went on to postulate the existence of the neutrino, which was confirmed in his lifetime. Following further development of his exclusion principle, Pauli was awarded the Nobel Prize in Physics in 1945 for his 'decisive contribution through his discovery of a new law of Nature'. He also had a long correspondence with Jung, and a reputation for accidentally breaking experimental equipment which was dubbed The Pauli Effect. With Frank Close Fellow Emeritus at Exeter College, University of Oxford Michela Massimi Professor of Philosophy of Science at the University of Edinburgh and Graham Farmelo Bye-Fellow of Churchill College, University of Cambridge Producer: Simon Tillotson.
2017-04-06
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The Paleocene-Eocene Thermal Maximum

Melvyn Bragg and guests discuss the high temperatures that marked the end of the Paleocene and start of the Eocene periods, about 50m years ago. Over c1000 years, global temperatures rose more than 5 C on average and stayed that way for c100,000 years more, with the surface of seas in the Arctic being as warm as those in the subtropics. There were widespread extinctions, changes in ocean currents, and there was much less oxygen in the sea depths. The rise has been attributed to an increase of carbon dioxide and methane in the atmosphere, though it is not yet known conclusively what the source of those gases was. One theory is that a rise in carbon dioxide, perhaps from volcanoes, warmed up the globe enough for warm water to reach the bottom of the oceans and so release methane from frozen crystals in the sea bed. The higher the temperature rose and the longer the water was warm, the more methane was released. Scientists have been studying a range of sources from this long period, from ice samples to fossils, to try to understand more about possible causes. With Dame Jane Francis Professor of Palaeoclimatology at the British Antarctic Survey Mark Maslin Professor of Palaeoclimatology at University College London And Tracy Aze Lecturer in Marine Micropaleontology at the University of Leeds Producer: Simon Tillotson.
2017-03-16
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The Kuiper Belt

Melvyn Bragg and guests discuss the Kuiper Belt, a vast region of icy objects at the fringes of our Solar System, beyond Neptune, in which we find the dwarf planet Pluto and countless objects left over from the origins of the solar system, some of which we observe as comets. It extends from where Neptune is, which is 30 times further out than the Earth is from the Sun, to about 500 times the Earth-Sun distance. It covers an immense region of space and it is the part of the Solar System that we know the least about, because it is so remote from us and has been barely detectable by Earth-based telescopes until recent decades. Its existence was predicted before it was known, and study of the Kuiper Belt, and how objects move within it, has led to a theory that there may be a 9th planet far beyond Neptune. With Carolin Crawford Public Astronomer at the Institute of Astronomy and Fellow of Emmanuel College, University of Cambridge Monica Grady Professor of Planetary and Space Sciences at the Open University And Stephen Lowry Reader in Planetary and Space Sciences, University of Kent Producer: Simon Tillotson.
2017-03-02
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Maths in the Early Islamic World

Melvyn Bragg and guests discuss the flourishing of maths in the early Islamic world, as thinkers from across the region developed ideas in places such as Baghdad's House of Wisdom. Among them were the Persians Omar Khayyam, who worked on equations, and Al-Khwarizmi, latinised as Algoritmi and pictured above, who is credited as one of the fathers of algebra, and the Jewish scholar Al-Samawal, who converted to Islam and worked on mathematical induction. As well as the new ideas, there were many advances drawing on Indian, Babylonian and Greek work and, thanks to the recording or reworking by mathematicians in the Islamic world, that broad range of earlier maths was passed on to western Europe for further study. With Colva Roney-Dougal Reader in Pure Mathematics at the University of St Andrews Peter Pormann Professor of Classics & Graeco-Arabic Studies at the University of Manchester And Jim Al-Khalili Professor of Physics at the University of Surrey Producer: Simon Tillotson.
2017-02-16
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Parasitism

Melvyn Bragg and guests discuss the relationship between parasites and hosts, where one species lives on or in another to the benefit of the parasite but at a cost to the host, potentially leading to disease or death of the host. Typical examples are mistletoe and trees, hookworms and vertebrates, cuckoos and other birds. In many cases the parasite species do so well in or on a particular host that they reproduce much faster and can adapt to changes more efficiently, and it is thought that almost half of all animal species have a parasitic stage in their lifetime. What techniques do hosts have to counter the parasites, and what impact do parasites have on the evolution of their hosts? With Steve Jones Emeritus Professor of Genetics at University College, London Wendy Gibson Professor of Protozoology at the University of Bristol and Kayla King Associate Professor in the Department of Zoology at the University of Oxford Producer: Simon Tillotson.
2017-01-26
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Johannes Kepler

Melvyn Bragg and guests discuss the German astronomer Johannes Kepler (1571 - 1630). Although he is overshadowed today by Isaac Newton and Galileo, he is considered by many to be one of the greatest scientists in history. The three laws of planetary motion Kepler developed transformed people's understanding of the Solar System and laid the foundations for the revolutionary ideas Isaac Newton produced later. Kepler is also thought to have written one of the first works of science fiction. However, he faced a number of challenges. He had to defend his mother from charges of witchcraft, he had few financial resources and his career suffered as a result of his Lutheran faith. With David Wootton Professor of History at the University of York Ulinka Rublack Professor of Early Modern European History at the University of Cambridge and Fellow of St John's College Adam Mosley Associate Professor in the Department of History at Swansea University Producer: Victoria Brignell.
2016-12-29
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John Dalton

The scientist John Dalton was born in North England in 1766. Although he came from a relatively poor Quaker family, he managed to become one of the most celebrated scientists of his age. Through his work, he helped to establish Manchester as a place where not only products were made but ideas were born. His reputation during his lifetime was so high that unusually a statue was erected to him before he died. Among his interests were meteorology, gasses and colour blindness. However, he is most remembered today for his pioneering thinking in the field of atomic theory. With: Jim Bennett Former Director of the Museum of the History of Science at the University of Oxford and Keeper Emeritus at the Science Museum Aileen Fyfe Reader in British History at the University of St Andrews James Sumner Lecturer in the History of Technology at the Centre for the History of Science, Technology and Medicine at the University of Manchester Producer: Victoria Brignell.
2016-10-27
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Plasma

Melvyn Bragg and guests discuss plasma, the fourth state of matter after solid, liquid and gas. As over ninety-nine percent of all observable matter in the Universe is plasma, planets like ours, with so little plasma and so much solid, liquid and gas, appear all the more remarkable. On the grand scale, plasma is what the Sun is made from and, when we look into the night sky, almost everything we can see with the naked eye is made of plasma. On the smallest scale, here on Earth, scientists make plasma to etch the microchips on which we rely for so much. Plasma is in the fluorescent light bulbs above our heads and, in laboratories around the world, it is the subject of tests to create, one day, an inexhaustible and clean source of energy from nuclear fusion. With Justin Wark Professor of Physics and Fellow of Trinity College at the University of Oxford Kate Lancaster Research Fellow for Innovation and Impact at the York Plasma Institute at the University of York and Bill Graham Professor of Physics at Queens University, Belfast Producer: Simon Tillotson.
2016-10-13
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Zeno's Paradoxes

Melvyn Bragg and guests discuss Zeno of Elea, a pre-Socratic philosopher from c490-430 BC whose paradoxes were described by Bertrand Russell as "immeasurably subtle and profound." The best known argue against motion, such as that of an arrow in flight which is at a series of different points but moving at none of them, or that of Achilles who, despite being the faster runner, will never catch up with a tortoise with a head start. Aristotle and Aquinas engaged with these, as did Russell, yet it is still debatable whether Zeno's Paradoxes have been resolved. With Marcus du Sautoy Professor of Mathematics and Simonyi Professor for the Public Understanding of Science at the University of Oxford Barbara Sattler Lecturer in Philosophy at the University of St Andrews and James Warren Reader in Ancient Philosophy at the University of Cambridge Producer: Simon Tillotson.
2016-09-22
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The Invention of Photography

Melvyn Bragg and guests discuss the development of photography in the 1830s, when techniques for 'drawing with light' evolved to the stage where, in 1839, both Louis Daguerre and William Henry Fox Talbot made claims for its invention. These followed the development of the camera obscura, and experiments by such as Thomas Wedgwood and Nicéphore Niépce, and led to rapid changes in the 1840s as more people captured images with the daguerreotype and calotype. These new techniques changed the aesthetics of the age and, before long, inspired claims that painting was now dead. With Simon Schaffer Professor of the History of Science at the University of Cambridge Elizabeth Edwards Emeritus Professor of Photographic History at De Montfort University And Alison Morrison-Low, Research Associate at National Museums Scotland Producer: Simon Tillotson.
2016-07-07
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Penicillin

Melvyn Bragg and guests discuss penicillin, discovered by Alexander Fleming in 1928. It is said he noticed some blue-green penicillium mould on an uncovered petri dish at his hospital laboratory, and that this mould had inhibited bacterial growth around it. After further work, Fleming filtered a broth of the mould and called that penicillin, hoping it would be useful as a disinfectant. Howard Florey and Ernst Chain later shared a Nobel Prize in Medicine with Fleming, for their role in developing a way of mass-producing the life-saving drug. Evolutionary theory predicted the risk of resistance from the start and, almost from the beginning of this 'golden age' of antibacterials, scientists have been looking for ways to extend the lifespan of antibiotics. With Laura Piddock Professor of Microbiology at the University of Birmingham Christoph Tang Professor of Cellular Pathology and Professorial Fellow at Exeter College at the University of Oxford And Steve Jones Emeritus Professor of Genetics at University College, London Producer: Simon Tillotson.
2016-06-09
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Euclid's Elements

Melvyn Bragg and guests discuss Euclid's Elements, a mathematical text book attributed to Euclid and in use from its appearance in Alexandria, Egypt around 300 BC until modern times, dealing with geometry and number theory. It has been described as the most influential text book ever written. Einstein had a copy as a child, which he treasured, later saying "If Euclid failed to kindle your youthful enthusiasm, then you were not born to be a scientific thinker." With Marcus du Sautoy Professor of Mathematics and Simonyi Professor for the Public Understanding of Science at the University of Oxford Serafina Cuomo Reader in Roman History at Birkbeck University of London And June Barrow-Green Professor of the History of Mathematics at the Open University Producer: Simon Tillotson.
2016-04-28
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1816, the Year Without a Summer

Melvyn Bragg and guests discuss the impact of the eruption of Mt Tambora, in 1815, on the Indonesian island of Sambawa. This was the largest volcanic eruption in recorded history and it had the highest death toll, devastating people living in the immediate area. Tambora has been linked with drastic weather changes in North America and Europe the following year, with frosts in June and heavy rains throughout the summer in many areas. This led to food shortages, which may have prompted westward migration in America and, in a Europe barely recovered from the Napoleonic Wars, led to widespread famine. With Clive Oppenheimer Professor of Volcanology at the University of Cambridge Jane Stabler Professor in Romantic Literature at the University of St Andrews And Lawrence Goldman Director of the Institute of Historical Research at the University of London Producer: Simon Tillotson.
2016-04-21
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The Neutron

Melvyn Bragg and guests discuss the neutron, one of the particles found in an atom's nucleus. Building on the work of Ernest Rutherford, the British physicist James Chadwick won the Nobel Prize for Physics for his discovery of the neutron in 1932. Neutrons play a fundamental role in the universe and their discovery was at the heart of developments in nuclear physics in the first half of the 20th century. With Val Gibson Professor of High Energy Physics at the University of Cambridge and fellow of Trinity College Andrew Harrison Chief Executive Officer of Diamond Light Source and Professor in Chemistry at the University of Edinburgh And Frank Close Professor Emeritus of Physics at the University of Oxford.
2016-04-14
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Robert Hooke

Melvyn Bragg and guests discuss the life and work of Robert Hooke (1635-1703) who worked for Robert Boyle and was curator of experiments at the Royal Society. The engraving of a flea, above, is taken from his Micrographia which caused a sensation when published in 1665. Sometimes remembered for his disputes with Newton, he studied the planets with telescopes and snowflakes with microscopes. He was an early proposer of a theory of evolution, discovered light diffraction with a wave theory to explain it and felt he was rarely given due credit for his discoveries. With David Wootton Anniversary Professor of History at the University of York Patricia Fara President Elect of the British Society for the History of Science And Rob Iliffe Professor of History of Science at Oxford University Producer: Simon Tillotson.
2016-02-18
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Chromatography

Melvyn Bragg and guests discuss the origins, development and uses of chromatography. In its basic form, it is familiar to generations of schoolchildren who put a spot of ink at the bottom of a strip of paper, dip it in water and then watch the pigments spread upwards, revealing their separate colours. Chemists in the 19th Century started to find new ways to separate mixtures and their work was taken further by Mikhail Tsvet, a Russian-Italian scientist who is often credited with inventing chromatography in 1900. The technique has become so widely used, it is now an integral part of testing the quality of air and water, the levels of drugs in athletes, in forensics and in the preparation of pharmaceuticals. With Andrea Sella Professor of Chemistry at University College London Apryll Stalcup Professor of Chemical Sciences at Dublin City University And Leon Barron Senior Lecturer in Forensic Science at King's College London.
2016-02-04
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Saturn

Melvyn Bragg and guests discuss the planet Saturn with its rings of ice and rock and over 60 moons. In 1610, Galileo used an early telescope to observe Saturn, one of the brightest points in the night sky, but could not make sense of what he saw: perhaps two large moons on either side. When he looked a few years later, those supposed moons had disappeared. It was another forty years before Dutch scientist Christiaan Huygens solved the mystery, realizing the moons were really a system of rings. Successive astronomers added more detail, with the greatest leaps forward in the last forty years. The Pioneer 11 spacecraft and two Voyager missions have flown by, sending back the first close-up images, and Cassini is still there, in orbit, confirming Saturn, with its rings and many moons, as one of the most intriguing and beautiful planets in our Solar System. With Carolin Crawford Public Astronomer at the Institute of Astronomy and Fellow of Emmanuel College, University of Cambridge Michele Dougherty Professor of Space Physics at Imperial College London And Andrew Coates Deputy Director in charge of the Solar System at the Mullard Space Science Laboratory at UCL.
2016-01-14
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Michael Faraday

Melvyn Bragg and guests discuss the eminent 19th-century scientist Michael Faraday. Born into a poor working-class family, he received little formal schooling but became interested in science while working as a bookbinder's apprentice. He is celebrated today for carrying out pioneering research into the relationship between electricity and magnetism. Faraday showed that if a wire was turned in the presence of a magnet or a magnet was turned in relation to a wire, an electric current was generated. This ground-breaking discovery led to the development of the electric generator and ultimately to modern power stations. During his life he became the most famous scientist in Britain and he played a key role in founding the Royal Institution's Christmas lectures which continue today. With: Geoffrey Cantor Professor Emeritus of the History of Science at the University of Leeds Laura Herz Professor of Physics at the University of Oxford Frank James Professor of the History of Science at the Royal Institution Producer: Victoria Brignell.
2015-12-24
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Circadian Rhythms

Melvyn Bragg and his guests discuss the evolution and role of Circadian Rhythms, the so-called body clock that influences an organism's daily cycle of physical, behavioural and mental changes. The rhythms are generated within organisms and also in response to external stimuli, mainly light and darkness. They are found throughout the living world, from bacteria to plants, fungi to animals and, in humans, are noticed most clearly in sleep patterns. With Russell Foster Professor of Circadian Neuroscience at the University of Oxford Debra Skene Professor of Neuroendocrinology at the University of Surrey And Steve Jones Emeritus Professor of Genetics at University College London.
2015-12-17
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P v NP

Melvyn Bragg and guests discuss the problem of P versus NP, which has a bearing on online security. There is a $1,000,000 prize on offer from the Clay Mathematical Institute for the first person to come up with a complete solution. At its heart is the question "are there problems for which the answers can be checked by computers, but not found in a reasonable time?" If the answer to that is yes, then P does not equal NP. However, if all answers can be found easily as well as checked, if only we knew how, then P equals NP. The area has intrigued mathematicians and computer scientists since Alan Turing, in 1936, found that it's impossible to decide in general whether an algorithm will run forever on some problems. Resting on P versus NP is the security of all online transactions which are currently encrypted: if it transpires that P=NP, if answers could be found as easily as checked, computers could crack passwords in moments. With Colva Roney-Dougal Reader in Pure Mathematics at the University of St Andrews Timothy Gowers Royal Society Research Professor in Mathematics at the University of Cambridge And Leslie Ann Goldberg Professor of Computer Science and Fellow of St Edmund Hall, University of Oxford Producer: Simon Tillotson.
2015-11-05
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Perpetual Motion

Melvyn Bragg and guests discuss the rise of the idea of perpetual motion and its decline, in the 19th Century, with the Laws of Thermodynamics. For hundreds of years, some of the greatest names in science thought there might be machines that could power themselves endlessly. Leonardo Da Vinci tested the idea of a constantly-spinning wheel and Robert Boyle tried to recirculate water from a draining flask. Gottfried Leibniz supported a friend, Orffyreus, who claimed he had built an ever-rotating wheel. An increasing number of scientists voiced their doubts about perpetual motion, from the time of Galileo, but none could prove it was impossible. For scientists, the designs were a way of exploring the laws of nature. Others claimed their inventions actually worked, and promised a limitless supply of energy. It was not until the 19th Century that the picture became clearer, with the experiments of James Joule and Robert Mayer on the links between heat and work, and the establishment of the First and Second Laws of Thermodynamics. With Ruth Gregory Professor of Mathematics and Physics at Durham University Frank Close Professor Emeritus of Physics at the University of Oxford and Steven Bramwell Professor of Physics and former Professor of Chemistry at University College London Producer: Simon Tillotson.
2015-09-24
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Extremophiles

In 1977, scientists in the submersible "Alvin" were exploring the deep ocean bed off the Galapagos Islands. In the dark, they discovered hydrothermal vents, like chimneys, from which superheated water flowed. Around the vents there was an extraordinary variety of life, feeding on microbes which were thriving in the acidity and extreme temperature of the vents. While it was already known that some microbes are extremophiles, thriving in extreme conditions, such as the springs and geysers of Yellowstone Park (pictured), that had not prepared scientists for what they now found. Since the "Alvin" discovery, the increased study of extremophile microbes has revealed much about what is and is not needed to sustain life on Earth and given rise to new theories about how and where life began. It has also suggested forms and places in which life might be found elsewhere in the Universe. With Monica Grady Professor of Planetary and Space Sciences at the Open University Ian Crawford Professor of Planetary Science and Astrobiology at Birkbeck University of London And Nick Lane Reader in Evolutionary Biochemistry at University College London Producer: Simon Tillotson.
2015-06-25
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The Science of Glass

While glass items have been made for at least 5,000 years, scientists are yet to explain, conclusively, what happens when the substance it's made from moves from a molten state to its hard, transparent phase. It is said to be one of the great unsolved problems in physics. While apparently solid, the glass retains certain properties of a liquid. At times, ways of making glass have been highly confidential; in Venice in the Middle Ages, disclosure of manufacturing techniques was a capital offence. Despite the complexity and mystery of the science of glass, glass technology has continued to advance from sheet glass to crystal glass, optical glass and prisms, to float glasses, chemical glassware, fibre optics and metal glasses. With: Dame Athene Donald Professor of Experimental Physics at the University of Cambridge and Master of Churchill College, Cambridge Jim Bennett Former Director of the Museum of the History of Science at the University of Oxford and Keeper Emeritus at the Science Museum Paul McMillan Professor of Chemistry at University College London Producer: Simon Tillotson.
2015-05-28
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The Earth's Core

Melvyn Bragg and his guests discuss the Earth's Core. The inner core is an extremely dense, solid ball of iron and nickel, the size of the Moon, while the outer core is a flowing liquid, the size of Mars. Thanks to the magnetic fields produced within the core, life on Earth is possible. The magnetosphere protects the Earth from much of the Sun's radiation and the flow of particles which would otherwise strip away the atmosphere. The precise structure of the core and its properties have been fascinating scientists from the Renaissance. Recent seismographs show the picture is even more complex than we might have imagined, with suggestions that the core is spinning at a different speed and on a different axis from the surface. With Stephen Blundell Professor of Physics and Fellow of Mansfield College at the University of Oxford Arwen Deuss Associate Professor in Seismology at Utrecht University and Simon Redfern Professor of Mineral Physics at the University of Cambridge Producer: Simon Tillotson.
2015-04-30
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The Curies

Melvyn Bragg and his guests discuss the scientific achievements of the Curie family. In 1903 Marie and Pierre Curie shared a Nobel Prize in Physics with Henri Becquerel for their work on radioactivity, a term which Marie coined. Marie went on to win a Nobel in Chemistry eight years later; remarkably, her daughter Irène Joliot-Curie would later share a Nobel with her husband Frédéric Joliot-Curie for their discovery that it was possible to create radioactive materials in the laboratory. The work of the Curies added immensely to our knowledge of fundamental physics and paved the way for modern treatments for cancer and other illnesses. With: Patricia Fara Senior Tutor of Clare College, University of Cambridge Robert Fox Emeritus Professor of the History of Science at the University of Oxford Steven T Bramwell Professor of Physics and former Professor of Chemistry at University College London Producer: Simon Tillotson.
2015-03-26
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Dark Matter

Melvyn Bragg and his guests discuss dark matter, the mysterious and invisible substance which is believed to make up most of the Universe. In 1932 the Dutch astronomer Jan Oort noticed that the speed at which galaxies moved was at odds with the amount of material they appeared to contain. He hypothesized that much of this 'missing' matter was simply invisible to telescopes. Today astronomers and particle physicists are still fascinated by the search for dark matter and the question of what it is. With Carolin Crawford Public Astronomer at the Institute of Astronomy, University of Cambridge and Gresham Professor of Astronomy Carlos Frenk Ogden Professor of Fundamental Physics and Director of the Institute for Computational Cosmology at the University of Durham Anne Green Reader in Physics at the University of Nottingham Producer: Simon Tillotson.
2015-03-12
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The Photon

Melvyn Bragg and his guests discuss the photon, one of the most enigmatic objects in the Universe. Generations of scientists have struggled to understand the nature of light. In the late nineteenth century it seemed clear that light was an electromagnetic wave. But the work of physicists including Planck and Einstein shed doubt on this theory. Today scientists accept that light can behave both as a wave and a particle, the latter known as the photon. Understanding light in terms of photons has enabled the development of some of the most important technology of the last fifty years. With: Frank Close Professor Emeritus of Physics at the University of Oxford Wendy Flavell Professor of Surface Physics at the University of Manchester Susan Cartwright Senior Lecturer in Physics and Astronomy at the University of Sheffield. Producer: Thomas Morris.
2015-02-12
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Behavioural Ecology

Melvyn Bragg and guests discuss Behavioural Ecology, the scientific study of animal behaviour. What factors influence where and what an animal chooses to eat? Why do some animals mate for life whilst others are promiscuous? Behavioural ecologists approach questions like these using Darwin's theory of natural selection, along with ideas drawn from game theory and the economics of consumer choice. Scientists had always been interested in why animals behave as they do, but before behavioural ecology this area of zoology never got much beyond a collection of interesting anecdotes. Behavioural ecology gave researchers techniques for constructing rigorous mathematical models of how animals act under different circumstances, and for predicting how they will react if circumstances change. Behavioural ecology emerged as a branch of zoology in the second half of the 20th century and proponents say it revolutionized our understanding of animals in their environments. GUESTS Steve Jones, Emeritus Professor of Genetics at University College London Rebecca Kilner, Professor of Evolutionary Biology at the University of Cambridge John Krebs, Principal of Jesus College at the University of Oxford Producer: Luke Mulhall.
2014-12-11
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Brunel

Melvyn Bragg and guests discuss Isambard Kingdom Brunel, the Victorian engineer responsible for bridges, tunnels and railways still in use today more than 150 years after they were built. Brunel represented the cutting edge of technological innovation in Victorian Britain, and his life gives us a window onto the social changes that accompanied the Industrial Revolution. Yet his work was not always successful, and his innovative approach to engineering projects was often greeted with suspicion from investors. Guests: Julia Elton, former President of the Newcomen Society for the History of Engineering and Technology Ben Marsden, Senior Lecturer in the School of Divinity, History and Philosophy at the University of Aberdeen Crosbie Smith, Professor of the History of Science at the University of Kent Producer: Luke Mulhall.
2014-11-13
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Nuclear Fusion

Melvyn Bragg and his guests discuss nuclear fusion, the process that powers stars. In the 1920s physicists predicted that it might be possible to generate huge amounts of energy by fusing atomic nuclei together, a reaction requiring enormous temperatures and pressures. Today we know that this complex reaction is what keeps the Sun shining. Scientists have achieved fusion in the laboratory and in nuclear weapons; today it is seen as a likely future source of limitless and clean energy. Guests: Philippa Browning, Professor of Astrophysics at the University of Manchester Steve Cowley, Chief Executive of the United Kingdom Atomic Energy Authority Justin Wark, Professor of Physics and fellow of Trinity College at the University of Oxford Producer: Thomas Morris.
2014-10-30
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e

Melvyn Bragg and his guests discuss Euler's number, also known as e. First discovered in the seventeenth century by the Swiss mathematician Jacob Bernoulli when he was studying compound interest, e is now recognised as one of the most important and interesting numbers in mathematics. Roughly equal to 2.718, e is useful in studying many everyday situations, from personal savings to epidemics. It also features in Euler's Identity, sometimes described as the most beautiful equation ever written. With: Colva Roney-Dougal Reader in Pure Mathematics at the University of St Andrews June Barrow-Green Senior Lecturer in the History of Maths at the Open University Vicky Neale Whitehead Lecturer at the Mathematical Institute and Balliol College at the University of Oxford Producer: Thomas Morris.
2014-09-25
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En liten tjänst av I'm With Friends. Finns även på engelska.
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