(Photograph) - Strato-spheres: Richard Mitchell, Brighton University's new professor of computing, used balloons in his inaugural lecture on Tuesday to illustrate issues facing software engineers as they learn the enormous complexity of systems while trying at the same time to make computers easier to use. Professor Mitchell argued that software engineering is different from other branches of engineering as it is not constrained by the physical world. He asked the audience to burst balloons to remember key points of his lecture