Witten Edward Witten & Sezgin Ergin Sezgin 
Topological Methods In Quantum Field Theories [PDF ebook] 

Over the last two decades, topological ideas have found increasingly more applications in quantum field theory. Topological field theories are the culmination of these developments, and they formed the dominating theme of the conference. The other focal point was two-dimensional quantum gravity. The participation of such leading mathematicians as M Atiyah, R Bott, G Segal, and I Singer, is a testmony to the deep interplay of mathematics and theoretical physics.