Melvyn Bragg and his guests discuss the life and work of Robert Boyle, a pioneering scientist and a founder member of the Royal Society. Born in Ireland in 1627, Boyle was one of the first natural philosophers to conduct rigorous experiments, laid the foundations of modern chemistry and derived Boyle's Law, describing the physical properties of gases. In addition to his experimental work he left a substantial body of writings about philosophy and religion; his piety was one of the most important...
Jun 12, 2014•47 min•Transcript available on Metacast Melvyn Bragg and his guests discuss photosynthesis, the process by which green plants and many other organisms use sunlight to synthesise organic molecules. Photosynthesis arose very early in evolutionary history and has been a crucial driver of life on Earth. In addition to providing most of the food consumed by organisms on the planet, it is also responsible for maintaining atmospheric oxygen levels, and is thus almost certainly the most important chemical process ever discovered. With: Nick L...
May 15, 2014•47 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the science of matter and the states in which it can exist. Most people are familiar with the idea that a substance like water can exist in solid, liquid and gaseous forms. But as much as 99% of the matter in the universe is now believed to exist in a fourth state, plasma. Today scientists recognise a number of other exotic states or phases, such as glasses, gels and liquid crystals - many of them with useful properties that can be exploited. With: Andrea Sell...
Apr 03, 2014•47 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the eye. Humans have been attempting to understand the workings and significance of the organ for at least 2500 years. Some ancient philosophers believed that the eye enabled creatures to see by emitting its own light. The function and structures of the eye became an area of particular interest to doctors in the Islamic Golden Age. In Renaissance Europe the work of thinkers including Kepler and Descartes revolutionised thinking about how the organ worked, but ...
Feb 27, 2014•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss Social Darwinism. After the publication of Charles Darwin's masterpiece On the Origin of Species in 1859, some thinkers argued that Darwin's ideas about evolution could also be applied to human society. One thinker particularly associated with this movement was Darwin's near-contemporary Herbert Spencer, who coined the phrase 'survival of the fittest'. He argued that competition among humans was beneficial, because it ensured that only the healthiest and most ...
Feb 20, 2014•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss Catastrophism, the idea that natural disasters have had a significant influence in moulding the Earth's geological features. In 1822 William Buckland, the first reader of Geology at the University of Oxford, published his famous Reliquae Diluvianae, in which he ascribed most of the fossil record to the effects of Noah's flood. Charles Lyell in his Principles of Geology challenged these writings, arguing that geological change was slow and gradual, and that the...
Jan 30, 2014•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss complexity and how it can help us understand the world around us. When living beings come together and act in a group, they do so in complicated and unpredictable ways: societies often behave very differently from the individuals within them. Complexity was a phenomenon little understood a generation ago, but research into complex systems now has important applications in many different fields, from biology to political science. Today it is being used to expla...
Dec 19, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the development of the microscope, an instrument which has revolutionised our knowledge of the world and the organisms that inhabit it. In the seventeenth century the pioneering work of two scientists, the Dutchman Antonie van Leeuwenhoek and Robert Hooke in England, revealed the teeming microscopic world that exists at scales beyond the capabilities of the naked eye. The microscope became an essential component of scientific enquiry by the nineteenth century,...
Nov 28, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the Roman physician and medical theorist Galen. The most celebrated doctor in the ancient world, Galen was Greek by birth but spent most of his career in Rome, where he was personal physician to three Emperors. He was one of the most prolific authors of his age, and a sixth of all surviving ancient literature in Greek was written by him. Celebrated in his own lifetime, he was regarded as the preeminent medical authority for centuries after his death, both in t...
Oct 10, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss exoplanets. Astronomers have speculated about the existence of planets beyond our solar system for centuries. Although strenuous efforts were made to find such planets orbiting distant stars, it was not until the 1990s that instruments became sophisticated enough to detect such remote objects. In 1992 Dale Frail and Aleksander Wolszczan discovered the first confirmed exoplanets: two planets orbiting the pulsar PSR B1257+12. Since then, astronomers have discove...
Oct 03, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests begin a new series of the programme with a discussion of the French polymath Blaise Pascal. Born in 1623, Pascal was a brilliant mathematician and scientist, inventing one of the first mechanical calculators and making important discoveries about fluids and vacuums while still a young man. In his thirties he experienced a religious conversion, after which he devoted most of his attention to philosophy and theology. Although he died in his late thirties, Pascal left a ...
Sep 19, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the invention of radio. In the early 1860s the Scottish physicist James Clerk Maxwell derived four equations which together describe the behaviour of electricity and magnetism. They predicted the existence of a previously unknown phenomenon: electromagnetic waves. These waves were first observed in the early 1880s, and over the next two decades a succession of scientists and engineers built increasingly elaborate devices to produce and detect them. Eventually ...
Jul 04, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss Einstein's theories of relativity. Between 1905 and 1917 Albert Einstein formulated a theoretical framework which transformed our understanding of the Universe. The twin theories of Special and General Relativity offered insights into the nature of space, time and gravitation which changed the face of modern science. Relativity resolved apparent contradictions in physics and also predicted several new phenomena, including black holes. It's regarded today as on...
Jun 06, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss cosmic rays. In 1912 the physicist Victor Hess discovered that the Earth is under constant bombardment from radiation coming from outside our atmosphere. These so-called cosmic rays have been known to cause damage to satellites and electronic devices on Earth, but most are absorbed by our atmosphere. The study of cosmic rays and their effects has led to major breakthroughs in particle physics. But today physicists are still trying to establish where these high...
May 16, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss one of the simplest and most remarkable of all molecules: water. Water is among the most abundant substances on Earth, covering more than two-thirds of the planet. Consisting of just three atoms, the water molecule is superficially simple in its structure but extraordinary in its properties. It is a rare example of a substance that can be found on Earth in gaseous, liquid and solid forms, and thanks to its unique chemical behaviour is the basis of all known li...
Mar 28, 2013•39 min•Transcript available on Metacast In a programme first broadcast in 2013, Melvyn Bragg and his guests discuss absolute zero, the lowest conceivable temperature. In the early eighteenth century the French physicist Guillaume Amontons suggested that temperature had a lower limit. The subject of low temperature became a fertile field of research in the nineteenth century, and today we know that this limit - known as absolute zero - is approximately minus 273 degrees Celsius. It is impossible to produce a temperature exactly equal t...
Mar 07, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the life and work of the Victorian anthropologist and archaeologist Augustus Pitt-Rivers. Over many years he amassed thousands of ethnographic and archaeological objects, some of which formed the founding collection of the Pitt Rivers Museum at Oxford University. Inspired by the work of Charles Darwin, Pitt-Rivers believed that human technology evolved in the same way as living organisms, and devoted much of his life to exploring this theory. He was also a pio...
Feb 28, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss comets, the 'dirty snowballs' of the Solar System. In the early 18th century the Astronomer Royal Sir Edmond Halley compiled a list of appearances of comets, bright objects like stars with long tails which are occasionally visible in the night sky. He concluded that many of these apparitions were in fact the same comet, which returns to our skies around every 75 years, and whose reappearance he correctly predicted. Halley's Comet is today the best known exampl...
Jan 17, 2013•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the history of crystallography, the study of crystals and their structure. The discovery in the early 20th century that X-rays could be diffracted by a crystal revolutionised our knowledge of materials. This crystal technology has touched most people's lives, thanks to the vital role it plays in diverse scientific disciplines - from physics and chemistry, to molecular biology and mineralogy. To date, 28 Nobel Prizes have been awarded to scientists working with...
Nov 28, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss Fermat's Last Theorem. In 1637 the French mathematician Pierre de Fermat scribbled a note in the margin of one of his books. He claimed to have proved a remarkable property of numbers, but gave no clue as to how he'd gone about it. "I have found a wonderful demonstration of this proposition," he wrote, "which this margin is too narrow to contain". Fermat's theorem became one of the most iconic problems in mathematics and for centuries mathematicians struggled ...
Oct 25, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the cell, the fundamental building block of life. First observed by Robert Hooke in 1665, cells occur in nature in a bewildering variety of forms. Every organism alive today consists of one or more cells: a single human body contains up to a hundred trillion of them. The first life on Earth was a single-celled organism which is thought to have appeared around three and a half billion years ago. That simple cell resembled today's bacteria. But eventually these ...
Sep 13, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss game theory, the mathematical study of decision-making. First formulated in the 1940s, the discipline entails devising 'games' to simulate situations of conflict or cooperation. It allows researchers to unravel decision-making strategies, and even to establish why certain types of behaviour emerge. Some of the games studied in game theory have become well known outside academia - they include the Prisoner's Dilemma, an intriguing scenario popularised in novels...
May 10, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the emergence of geology as a scientific discipline. A little over two hundred years ago a small group of friends founded the Geological Society of London. This organisation was the first devoted to furthering the discipline of geology - the study of the Earth, its history and composition. Although geology only emerged as a separate area of study in the late eighteenth century, many earlier thinkers had studied rocks, fossils and the materials from which the E...
Apr 12, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the measurement of time. Early civilisations used the movements of heavenly bodies to tell the time, but even in the ancient world more sophisticated timekeeping devices such as waterclocks were known. The development of mechanical clocks in Europe emerged in the medieval period when monks used such devices to sound an alarm to signal it was the hour to pray, although these clocks did not tell them the time. For hundreds of years clocks were inaccurate and it ...
Mar 29, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the physics of electrical conduction. Although electricity has been known for several hundred years, it was only in the early twentieth century that physicists first satisfactorily explained the phenomenon. Electric current is the passage of charged particles through a medium - but a material will only conduct electricity if its atomic structure enables it to do so. In investigating electrical conduction scientists discovered two new classes of material. Semic...
Feb 23, 2012•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the evolution of the Scientific Method, the systematic and analytical approach to scientific thought. In 1620 the great philosopher and scientist Francis Bacon published the Novum Organum, a work outlining a new system of thought which he believed should inform all enquiry into the laws of nature. Philosophers before him had given their attention to the reasoning that underlies scientific enquiry; but Bacon's emphasis on observation and experience is often see...
Jan 26, 2012•42 min•Transcript available on Metacast Melvyn Bragg and guests discuss the giant molecules that form the basis of all life. Macromolecules, also known as polymers, are long chains of atoms. They form the proteins that make up our bodies, as well as many of the materials of modern life. Man's ability to mimic the structure of macromolecules has led to the invention of plastics such as nylon, paints and adhesives. Most of our clothes are made of macromolecules, and our food is macromolecular. The medical sciences are making increasingl...
Dec 29, 2011•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the Hippocratic Oath. The Greek physician Hippocrates, active in the fifth century BC, has been described as the father of medicine, although little is known about his life and some scholars even argue that he was not one person but several. A large body of work originally attributed to him, the Hippocratic Corpus, was disseminated widely in the ancient world, and contains treatises on a wide variety of subjects, from fractures to medical ethics.Today we know ...
Sep 15, 2011•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the origins of infectious disease. Infectious disease has been with us for millennia. There are reports of ancient outbreaks of plague in the Bible, and in numerous historical sources from China, the Middle East and Europe. Other infections, including smallpox, tuberculosis and measles, have also been known for centuries. But some diseases made their first appearances only recently: HIV emerged around a century ago, while the Ebola virus was first recorded in ...
Jun 08, 2011•42 min•Transcript available on Metacast Melvyn Bragg and his guests discuss the neutrino.In 1930 the physicist Wolfgang Pauli proposed the existence of an as-yet undiscovered subatomic particle. He also bet his colleagues a case of champagne that it would never be detected. He lost his bet when in 1956 the particle, now known as the neutrino, was first observed in an American nuclear reactor. Neutrinos are some of the most mysterious particles in the Universe. The Sun produces trillions of them every second, and they constantly bombar...
Apr 14, 2011•42 min•Transcript available on Metacast