Biswas worked in several diverse areas of theoretical high energy physics and particle physics, that includes his early work in collaboration with Herbert S. Green on the Bethe-Salpeter equation and its solution, several investigations in particle physics phenomenology, two-dimensional quantum electrodynamics, analysis of anharmonic oscillator in quantum mechanics, scattering theory, study of dispersion relations in collision processes of elementary particles based on unitarity and analyticity, geometric phases of wave function in quantum mechanics and quantum optics, equation of state of neutron stars, quark stars, weak interaction processes, weak decays involving neutral currents, processes involving stellar energy loss, supersymmetry in weak currents, chiral anomalies, super-propagator for a non-polynomial field, phase transitions in gauge theories, development of supersymmetric classical mechanics, supersymmetric quantum mechanics, stochastic quantization, quark stars, continued fraction theory, role of parastatistics in statistical mechanics,