This module is concerned with the primitive concepts of space, of time and of matter, examined in a historical context as well as what they lead to in the light of modern physics, specifically Einstein’s General Theory of Relativity. Students will explore the nature of space and time, mass and energy, in relation to a description of physical reality. It discusses the evolution of our understanding of these fundamental concepts from Aristotle to Einstein, and begins with commonsensical, intuitive ideas of space, time and about gravity, demonstrating how these had to be radically revised over centuries in order to correctly describe nature as best we know it now. Three strands, namely the philosophical, mathematical and physical aspects, are used as the framework for examining the central issues involved.
The module gradually leads the student to the modern physical viewpoint of Einsteinian relativity in which space, time and matter are not only intimately related, but in a sense actually unified. We hope to impart a critical appreciation of the concepts discussed as well as the ability to perform simple calculations that quantitatively explore some of the implications of these profound ideas for cosmology. What is the shape and size of the Universe; how old is it? Indeed, is it even meaningful to ask such questions in the first place? The treatment will in general emphasise the role of fundamental or primitive concepts and ideas in the evolution of our theoretical or mental picture of the physical universe and how these get modified and extended by taking into account new ‘facts’ provided by observation and experiment.
To adapt a quote from the preface to the book ‘The Evolution of Physics’ by Einstein and Infeld: “… You may find it boring or interesting, dull or exciting, but our aim will be accomplished if this module gives you some idea of the eternal struggle of the inventive human mind for a fuller understanding of the laws governing physical phenomena.”