Das, Saurya
https://hdl.handle.net/10133/3587
2019-03-20T14:47:37ZElectromagnetic charge-monopole versus gravitational scattering at Planckian energies
https://hdl.handle.net/10133/4566
Electromagnetic charge-monopole versus gravitational scattering at Planckian energies
Das, Saurya; Majumdar, Parthasarathi
The amplitude for the scattering of a point magnetic monopole and a point charge, at center-of-
mass energies much larger than the masses of the particles, and in the limit of low momentum
transfer, is shown to be proportional to the (integer-valued) monopole strength, assuming the Dirac
quantization condition for the monopole-charge system. It is demonstrated that, for small momentum
transfer, charge-monopole electromagnetic effects remain comparable to those due to the
gravitational interaction between the particles even at Planckian center-of-mass energies.
Sherpa Romeo green journal
1994-01-01T00:00:00ZElectromagnetic and gravitational scattering at Planckian energies
https://hdl.handle.net/10133/4565
Electromagnetic and gravitational scattering at Planckian energies
Das, Saurya; Majumdar, Parthasarathi
The scattering of pointlike particles at a very large center-of-mass energies and fixed low momentum transfers, occurring due to both their electromagnetic and gravitational interactions, is reexamined in the particular case when one of the particles carries a magnetic charge. At Planckian center-of-mass energies, when gravitational dominance is usually expected, the presence of magnetic charge is show to produce dramatic modifications to the scattering cross section as well as to holomorphic structure of the scattering amplitude.
Sherpa Romeo green journal
1995-01-01T00:00:00ZShock wave mixing in Einstein and dilaton gravity
https://hdl.handle.net/10133/4470
Shock wave mixing in Einstein and dilaton gravity
Das, Saurya; Majumdar, Parthasarathi
We consider possible mixing of electromagnetic and gravitational shock waves, in the Planckian energy scattering of point
particles in Minkowski space, By boosting a Reissner-Nordstriim black hole solution to the velocity of light, it is shown
that no mixing of shock waves takes place for arbitrary finite charge carried by the black hole. However, a similar boosting
procedure for a charged black hole solution in dilaton gravity yields some mixing: the wave function of even a neutral test
particle, acquires a small additional phase factor depending on the dilalonic black hole charge. Possible implications for poles
in the amplitudes for the dilaton gravity case are discussed
Sherpa Romeo green journal
1995-01-01T00:00:00ZAspects of Planckian scattering beyond the eikonal
https://hdl.handle.net/10133/4469
Aspects of Planckian scattering beyond the eikonal
Das, Saurya; Majumdar, Parthasarathi
We discuss an approach to compute two-particle scattering amplitudes for spinless light
particles colliding at Planckian centre-of-mass energies, with increasing momentum transfer away
from the eikonal limit. The leading corrections to the eikonal amplitude, in our 'external metric'
approach, are shown to be vanishingly small in the limit of the source particle mass going to zero.
For massless charged particles, the electromagnetic and gravitational interactions decouple in the
eikonal limit, hut mix non-trivially for the leading order corrections.
Sherpa Romeo green journal
1998-01-01T00:00:00Z