2 papers
hep-th2024
Soft zero for cylindrical gravitational waves
Robert Penna
The graviton S-matrix has a famous soft pole. We show that the S-matrix for cylindrical gravitational waves has a soft zero. The soft pole for ordinary gravitons comes from a Ward…
hep-th2023
A nonlocal charge for cylindrical gravitational waves
Robert F. Penna
The classical scattering of cylindrical gravitational waves is exactly solvable. The motivation for this paper is to understand if the quantum scattering problem is also exactly so…