Physics and Cosmology


Duration: 45 minutes
First broadcast: Thursday 29 May 2008

Melvyn Bragg and guests discuss the strange mathematics of probability where heads or tails is a simple question with a far from simple answer.

Gambling may be as old as the hills but probability as a mathematical discipline is a relative youngster. Probability is the field of maths relating to random events and, although commonplace now, the idea that you can pluck a piece of maths from the tumbling of dice, the shuffling of cards or the odds in the local lottery is a relatively recent and powerful one. It may start with the toss of a coin but probability reaches into every area of the modern world, from the analysis of society to the decay of an atom.

With Marcus du Sautoy, Professor of Mathematics at the University of Oxford; Colva Roney-Dougal, Lecturer in Pure Mathematics at the University of St Andrews; Ian Stewart, Professor of Mathematics at the University of Warwick

The Multiverse

Duration: 45 minutes
First broadcast: Thursday 21 February 2008

Melvyn Bragg and guests will be leaving the studio, the planet and indeed, the universe to take a tour of the Multiverse.

If you look up the word ‘universe’ in the Oxford English Dictionary you will find the following definition:
“The whole of created or existing things regarded collectively; all things (including the earth, the heavens, and all the phenomena of space) considered as constituting a systematic whole.”

That sounds fairly comprehensive as a description of everything, but for an increasing number of physicists and cosmologists the universe is not enough. They talk of a multiverse – literally many universes – to explain aspects of their theory, the character of the universe and the riddle of our existence within it. Indeed, compared to the scope and complexity of the multiverse, the whole of our known reality may be as a speck of sand upon a beach.

The idea of a multiverse is still controversial, some argue that it isn’t even science, because it is based on an idea that we may never be able to prove or even see. But what might a multiverse be like, why are physicists and cosmologists increasingly interested in it and is it really scientific to discuss the existence of universes we may never know anything

With Martin Rees, President of the Royal Society and Professor of Cosmology and Astrophysics at the University of Cambridge; Fay Dowker, Reader in Theoretical Physics at Imperial College; Bernard Carr, Professor of Mathematics and Astronomy at Queen Mary, University of London


Duration: 45 minutes
First broadcast: Thursday 04 October 2007

Melvyn Bragg and guests discuss Antimatter, a type of particle predicted by the British physicist, Paul Dirac. Dirac once declared that “The laws of nature should be expressed in beautiful equations”. True to his word, he is responsible for one of the most beautiful. Formulated in 1928, it describes the behaviour of electrons and is called the Dirac equation.

But the Dirac equation is strange. For every question it gives two answers – one positive and one negative. From this its author concluded that for every electron there is an equal and opposite twin. He called this twin the anti-electron and so the concept of antimatter was born.

Despite its popularity with Science Fiction writers, antimatter is relatively mundane in physics – we have created antimatter in the laboratory and we even use it in our hospitals. But one fundamental question remains – why isn’t there more antimatter in the universe. Answering that question will involve developing new physics and may take us closer to understanding events at the origin of the universe.

With Val Gibson, Reader in High Energy Physics at the University of Cambridge; Frank Close, Professor of Physics at Exeter College, University of Oxford; Ruth Gregory, Professor of Mathematics and Physics at the University of Durham