Ramond played a major role in the development of superstring theory In 1971, Ramond generalized Dirac s work for point like particles to stringlike ones In this process he discovered two dimensional supersymmetry and laid the ground for supersymmetry in four spacetime dimensions He found the spectrum of fermionic modes in string theory and the paper started superstring theory From this paper Andr Neveu and John Schwarz developed a string theory with both fermions and bosons.According to quantum mechanics, particles can be divided into two types bosons and fermions The distinction between bosons and fermions is basic Fermions are particles which have half integer spin 1 2, 3 2, 5 2 and so on , measured in units of Planck s constant and bosons are particles which have integer spin 0, 1, 2 and so on , measured in units of Planck s constant Examples of fermions are quarks, leptons and baryons Quantum of fundamental forces such as gravitons, photons, etc are all bosons In quantum field theory, fermions interact by exchanging bosons.Early string theory proposed by Yoichiro Nambu and others in 1970 was only a bosonic string Ramond completed the theory by inventing a fermionic string to accompany the bosonic ones The Virasoro algebra which is the symmetry algebra of the bosonic string was generalized to a superconformal algebra the Ramond algebra, an example of a super Virasoro algebra including anticommuting operators also.

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