Melvyn Bragg and guests discuss mysterious phenomena called Gravitational Waves in contemporary physics. The rather un-poetically named star SN 2006gy is roughly 150 times the size of our sun. Last week it went supernova, creating the brightest stellar explosion ever recorded. But among the vast swathes of dust, gas and visible matter ejected into space, perhaps the most significant consequences were invisible – emanating out from the star like the ripples from a pebble thrown into a pond. They are called Gravitational Waves, predicted by Einstein and much discussed since, their existence has never actually been proved but now scientists may be on the verge of measuring them directly. To do so would give us a whole new way of seeing the cosmos. But what are gravitational waves, why are scientists trying to measure them and, if they succeed, what would a gravitational picture of the universe look like?With Jim Al-Khalili, Professor of Physics at the University of Surrey; Carolin Crawford, Royal Society Research Fellow at the Institute of Astronomy, Cambridge; Sheila Rowan, Professor in Experimental Physics in the Department of Physics and Astronomy at the University of Glasgow

Melvyn Bragg and guests discuss Victorian Pessimism. On 1 September 1851 the poet Matthew Arnold was on his honeymoon. Catching a ferry from Dover to Calais, he sat down and worked on a poem that would become emblematic of the fears and anxieties of a generation of Victorians. It is called Dover Beach and it finishes like this: “Ah, love, let us be true To one another! for the world, which seemsTo lie before us like a land of dreams,So various, so beautiful, so new,Hath really neither joy, nor love, nor light,Nor certitude, nor peace, nor help for pain;And we are here as on a darkling plainSwept with confused alarms of struggle and flight,Where ignorant armies clash by night”.From Matthew Arnold’s poem Dover Beach to the malign universe of Thomas Hardy’s novels, an age famed for its forthright sense of progress and Christian belief was also riddled with anxieties about faith, morality and the future of the human race. They were even worried that the sun would soon go out. But to what extent was this pessimism spread across all areas of Victorian life? What events and ideas were driving it on and were any of their concerns about race, religion, class and culture borne out as the 19th century drew to a close? With Dinah Birch, Professor of English at the University of Liverpool; Rosemary Ashton, Quain Professor of English Language and Literature at University College London; Peter Mandler, University Lecturer and Fellow in History at Gonville and Caius College, Cambridge.

Melvyn Bragg discusses the Dutch Jewish Philosopher Spinoza. For the radical thinkers of the Enlightenment, he was the first man to have lived and died as a true atheist. For others, including Samuel Taylor Coleridge, he provides perhaps the most profound conception of God to be found in Western philosophy. He was bold enough to defy the thinking of his time, yet too modest to accept the fame of public office and he died, along with Socrates and Seneca, one of the three great deaths in philosophy. Baruch Spinoza can claim influence on both the Enlightenment thinkers of the 18th century and great minds of the 19th, notably Hegel, and his ideas were so radical that they could only be fully published after his death. But what were the ideas that caused such controversy in Spinoza’s lifetime, how did they influence the generations after, and can Spinoza really be seen as the first philosopher of the rational Enlightenment?With Jonathan Rée, historian and philosopher and Visiting Professor at Roehampton University; Sarah Hutton, Professor of English at the University of Wales, Aberystwyth; John Cottingham, Professor of Philosophy at the University of Reading.

Melvyn Bragg and guests discuss Greek and Roman love poetry, from the Greek poet Sappho and her erotic descriptions of romance on Lesbos, to the love-hate poems of the Roman writer Catullus. The source of many of the images and metaphors of love that have survived in literature through the centuries. We begin with the words of Sappho, known as the Tenth Muse and one of the great love poets of Ancient Greece: “Love, bittersweet and inescapable, creeps up on me and grabs me once again”Such heartfelt imploring by Sappho and other writers led poetry away from the great epics of Homer and towards a very personal expression of emotion. These outpourings would have been sung at intimate gatherings, accompanied by the lyre and plenty of wine. The style fell out of fashion only to be revived first in Alexandria in the third Century BC and again by the Roman poets starting in the 50s BC. Catullus and his peers developed the form, employing powerful metaphors of war and slavery to express their devotion to their Beloved – as well as the ill treatment they invariably received at her hands!So why did Greek poetry move away from heroic narratives and turn to love in the 6th Century BC? How did the Romans transform the genre? And what effect did the sexual politics of the day have on the form? With Nick Lowe, Senior Lecturer in Classics at Royal Holloway, University of London; Edith Hall, Professor of Classics and Drama at Royal Holloway, University of London; Maria Wyke, Professor of Latin at University College London.

Melvyn Bragg and guests discuss symmetry. Found in Nature - from snowflakes to butterflies - and in art in the music of Bach and the poems of Pushkin, symmetry is both aesthetically pleasing and an essential tool to understanding our physical world. The Greek philosopher Aristotle described symmetry as one of the greatest forms of beauty to be found in the mathematical sciences, while the French poet Paul Valery went further, declaring; “The universe is built on a plan, the profound symmetry of which is somehow present in the inner structure of our intellect”.The story of symmetry tracks an extraordinary shift from its role as an aesthetic model - found in the tiles in the Alhambra and Bach's compositions - to becoming a key tool to understanding how the physical world works. It provides a major breakthrough in mathematics with the development of group theory in the 19th century. And it is the unexpected breakdown of symmetry at sub-atomic level that is so tantalising for contemporary quantum physicists.So why is symmetry so prevalent and appealing in both art and nature? How does symmetry enable us to grapple with monstrous numbers? And how might symmetry contribute to the elusive Theory of Everything?With Fay Dowker, Reader in Theoretical Physics at Imperial College, London; Marcus du Sautoy, Professor of Mathematics at the University of Oxford; Ian Stewart, Professor of Mathematics at the University of Warwick.

Melvyn Bragg discusses the Opium Wars, a series of conflicts in the 19th Century which had a profound effect on British Chinese relations for generations. Thomas De Quincey describes the pleasures of opium like this: “Thou hast the keys of Paradise, O just, subtle and mighty opium”. The Chinese had banned opium in its various forms several times, citing concern for public morals, but private British traders continued to smuggle large quantities of opium into China from India. In this way, the opium trade became a way of balancing a trade deficit brought about by Britain's own addiction...to Indian tea.The Chinese protested against the flouting of the ban, even writing to Queen Victoria. But the British continued to trade, leading to a crackdown by Lin Tse-Hsu, a man appointed to be China's Opium Drugs Czar. He confiscated opium from the British traders and destroyed it. The British military response was severe, leading to the Nanking Treaty which opened up several of China's ports to foreign trade and gave Britain Hong Kong. The peace didn't last long and a Second Opium War followed. The Chinese fared little better in this conflict, which ended with another humiliating treaty.So what were the main causes of the Opium Wars? What were the consequences for the Qing dynasty? And how did the punitive treaties affect future relations with Britain?With Yangwen Zheng, Lecturer in Modern Chinese History at the University of Manchester; Lars Laamann, Research Fellow in Chinese History at the School of Oriental and African Studies (SOAS), University of London; Xun Zhou, Research Fellow in History at SOAS, University of London

Melvyn Bragg and guests discuss the 7th century saint, Hilda, or Hild as she would have been known then, wielded great religious and political influence in a volatile era. The monasteries she led in the north of England were known for their literacy and learning and produced great future leaders, including 5 bishops. The remains of a later abbey still stand in Whitby on the site of the powerful monastery she headed there. We gain most of our knowledge of Hilda's life from The Venerable Bede who wrote that she was 66 years in the world, living 33 years in the secular life and 33 dedicated to God. She was baptised alongside the king of Northumbria and with her royal connections, she was a formidable character. Bede writes: “Her prudence was so great that not only indifferent persons but even kings and princes asked and received her advice”. Hild and her Abbey at Whitby hosted the Synod which decided when Easter would be celebrated, following a dispute between different traditions. Her achievements are all the more impressive when we consider that Christianity was still in its infancy in Northumbria. So what contribution did she make to establishing Christianity in the north of England? How unusual was it for a woman to be such an important figure in the Church at the time? How did her double monastery of both men and women operate on a day-to-day basis? And how did she manage to convert a farmhand into England's first vernacular poet?With John Blair, Fellow in History at The Queen's College, Oxford; Rosemary Cramp, Emeritus Professor in Archaeology at Durham University; Sarah Foot, Professor of Early Medieval History at Sheffield University.

Melvyn Bragg and guests discuss the history of anaesthetics, from laughing gas in the 1790s to the discovery of “blessed chloroform”. Remembering his unsuccessful stint at Edinburgh Medical school Charles Darwin described the horrors of surgery before anaesthetics : "I attended the operating theatre and saw two very bad operations... but I rushed away before they were completed. Nor did I ever attend again, for hardly any inducement would have been strong enough to make me do so; this being long before the blessed days of chloroform. The two cases fairly haunted me for many a long year."The suffering Darwin witnessed is almost unimaginable. In the 19th Century, a simple fracture often led to amputation carried out on a conscious patient, whose senses would be dulled only by brandy or perhaps some morphine. Many patients died of shock.The properties of gases like nitrous oxide or “laughing gas” held out hope. The chemist Humphrey Davy in the 1790s described it as “highly pleasurable, thrilling”. He also noticed his toothache disappeared. But he failed to apply his observations and it wasn't until the 1840s that there was a major breakthrough in anaesthetics, when an enterprising dentist in Boston managed to anaesthetize a patient with ether. It became known as the “Yankee Dodge”. Ether had its drawbacks and the search for a suitable alternative continued until chloroform was tried in 1847, winning many admirers including Queen Victoria, the first English royal to use it. So why did it take so long for inhaled gases to advance from providing merely recreational highs to providing an essential tool of humane surgery? What role did the development of the atomic bomb play in the development of anaesthetics? And how have society's changing attitudes to pain informed the debate?With David Wilkinson, Consultant Anaesthetist at St Bartholomew’s Hospital in London and President of the History of Anaesthesia Society; Stephanie Snow, Research Associate at the Centre for the History of Science, Technology & Medicine at the University of Manchester; Anne Hardy, Professor in the History of Modern Medicine at University College London

Melvyn Bragg and guests discuss the original Iron Chancellor, Otto Von Bismarck. One of Europe's leading statesmen in the 19th Century he is credited with unifying Germany under the military might of his home state of Prussia. An enthusiastic expansionist, Bismarck undertook a war against Denmark that has become a by-word for incomprehensible conflict. The British Prime Minister, Lord Palmerston, said: “The Schleswig-Holstein question is so complicated, only three men in Europe have ever understood it. One was Prince Albert, who is dead. The second was a German professor who became mad. I am the third and I have forgotten all about it.”After vanquishing Austria and France, Bismark led the new industrialising Germany, managing to remain in power for a further two decades. Bismarck said: “The art of statesmanship is to steer a course on the stream of time” and he founded one of Europe's first welfare states but he was also known for his ruthless tactics, ignoring democratic institutions, dabbling in dirty politics, leaking to the press and bribing journalists. Was the unification of Germany a carefully planned campaign or a series of unpredictable events that Bismarck made the most of? Did his encouragement of militaristic nationalism bear fruit in Nazi Germany, and what is his legacy today in contemporary Germany?With Richard J Evans, Professor of Modern History at the University of Cambridge; Christopher Clark, Reader in Modern European History at the University of Cambridge; and Katharine Lerman, Senior Lecturer in Modern European History at London Metropolitan University

Melvyn Bragg and guests discuss the great 18th Century fashion for epistolary literature. From its first appearance in the 17th Century with writers like Aphra Behn, epistolary fiction, fiction in the form of letters, reached its heyday in the 18th Century with works like Clarissa by Samuel Richardson. At over a million words, it's a contender for the longest English novel. It inspired impassioned followers such as Denis Diderot who described reading Richardson's novels like this: “In the space of a few hours I had been through a host of situations which the longest life can scarcely provide in its whole course. I had heard the genuine language of the passions; I had seen the secret springs of self-interest and self-love operating in a hundred different ways: I had become privy to a multitude of incidents and I felt I had gained in experience.”This sense of the reader gaining a privileged peek into the psychology of the protagonists was a key device of the epistolary form and essential to the development of the novel. Its emphasis on moral instruction also propelled the genre into literary respectability. These novels were a publishing sensation. Philosophers like Rousseau and Montesquieu took up the style, using it to convey their ideas on morality and society.So why was letter writing so important to 18th Century authors? How did this style aid the development of the novel? And why did epistolary literature fall out of favour?With John Mullan, Professor of English at University College London; Karen O’Brien, Professor in English at the University of Warwick; and Brean Hammond, Professor of Modern English Literature at the University of Nottingham.