T Pradhan
Articles written in Pramana – Journal of Physics
Volume 6 Issue 5 May 1976 pp 312-322 Quantum Mechanics
Feynman diagram method for atomic collisions
Feynman diagram method of treating atomic collision problems in perturbation theory is presented and matrix elements are calculated for a number of processes. The result for the resonant charge transfer in hydrogen is identical to the well known OBK value. However, in processes like collisional ionisation, the results are different from those obtained by conventional methods.
Volume 17 Issue 3 September 1981 pp 287-295 Particle Physics
Confinement of massless particles: Photon
Confinement of massless particles in a suitably chosen dielectric medium is considered. Light waves of selected frequencies are shown to be confined in a medium with dielectric constant
Volume 22 Issue 2 February 1984 pp 97-106 Nuclear And Particle Physics
Colour dielectric model of the proton
A model of the proton with its constituent quarks bound in a colour polarizable medium with dielectric constant varying as (
Volume 22 Issue 3-4 March 1984 pp 237-246 Particle Physics
A new approach to particle confinement
A new approach to permanent confinement of non-relativistic and relativistic particles inside microscopic regions of space is presented. Motion in suitably chosen energy-dependent potentials turns out to be such that the size of orbits of particles bound in such potentials decreases when energy is supplied to them from external sources and there exists a maximum size of these orbits. The energy spectrum is purely discrete without any continuum. The dynamics of such particles requires the introduction of a space-dependent metric in the Hilbert space of states to ensure conservation of probability.
Volume 24 Issue 1-2 January 1985 pp 77-94 Particle Physics
The fifth interaction: universal long range force between spins
In this paper we present a review of our investigations on universal long range force between spins mediated by a massless axial vector gauge field which we name as “axial photon”. The invariance of the Lagrangian field theory of particles, possessing spin degrees of freedom, under local Lorentz transformations, necessitates the introduction of such an axial vector gauge field which interacts with spin current of the particles. Classical as well as quantum dynamics of electrons interacting with photon and axial photon are worked out. The new interaction is found to be asymptotically free. It is shown that
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