2025/06/14 by Aakash Kumar, Kumar, Aakash, Arnab Rudra +2
Earth and Planetary Sciences · Physics and Astronomy · #Atomic and Subatomic Physics Research #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #High Energy Physics - Theory (hep-th) #High-pressure geophysics and materials #Quantum, superfluid, helium dynamics
paper · pdf · doi:10.48550/arxiv.2506.12431
openalex publication_date 2025/06/14 · openalex created_date 2025/10/13 · openalex updated_date 2026/07/28
In gauge theories, contact terms play an important role in ensuring gauge invariance. In the spinor helicity formalism, the choice of a gauge-fixing condition manifests itself in the form of the choice of reference vector to write the massless polarization vector(s). However, this choice must be irrelevant in any gauge-invariant observable. We use this principle to determine contact term for Electromagnetic Compton amplitude. We considered three-point function between two massive particles & a photon to be one which is responsible for soft photon theorem/Coulomb and demonstrate that it is possible to use the above-mentioned principle to find the contact term for the tree-level Compton amplitude of two bosonic massive spinning particles and two photons. The final result does not suffer from any spurious poles.