Space and Time: From Antiquity to Einstein and Beyond

At the beginning of the 20th century, Einstein revolutionized the notions of space and time, first through special relativity and then, a decade later, through general relativity. Conceptual ideas underlying general relativity are explained and its physical ramifications summarized in general terms, without recourse to advanced mathematics. This theory is perhaps the most sublime creation of the human mind. Nonetheless, it has become increasingly clear that it too has serious limitations which can be overcome only through another dramatic revision of our notions of space and time. The article concludes by providing glimpses of what awaits us in the 21st century. Based on a public lecture given under the auspices of National Institute of Advanced Studies and Raman Research Institute, Bangalore on 22 December 2004.