On Start the Week Allan Little grapples with super-symmetric particles, superstrings and multiverses with the help of Jon Butterworth. But the writer Jim Baggott dismisses many of the ideas of modern theoretical physics as mere fairy tales and fantasy. The sociologist Hilary Rose bemoans the commercialisation of biological sciences and warns against believing the hype. But the world-renowned stem cell scientist Stephen Minger believes recent developments show great promise for the treatments of many life-threatening diseases.