Dr Majumdar has done valuable work on problems of finite Heisenberg chains, critical parameters in phase transitions and positron annihilation. The calculations of effective magnetic moment, specific heat and other physical quantities for finite Heisenberg chains constitute important contribution. These calculations showed the existence of violation of the non-crossing and non-degeneracy rules. He has determined the critical parameters of ferromagnetic Ising model and gas-liquid transition. His work on positron annihilation has provided a theoretical basis for the measurement of the Fermi momentum of metals. His pioneering study of bound magnon states using techniques borrowed from scattering theory enables one to compute bound magnon states. Such bound magnon states were verified experimentally.