My research is concerned with the search for a unified theory of the laws of nature. Unification has been one the
main themes in the history of science, as time and again diverse phenomena have been understood in terms of smaller and simpler building blocks. We believe that we are close to a complete theory that would incorporate both gravity and the elementary particle forces in a quantum mechanical framework. In this theory the elementary particles are actually one-dimensional objects, tiny loops of `string.' All of the forces and particles can be understood as different states of vibration of the string.