# Symmetric point 4-point functions at one loop in QCD

## TL;DR

This paper computes one-loop four-point Green's functions in QCD and QED at the symmetric point, providing detailed analytical expressions in a covariant gauge for theoretical and computational applications.

## Contribution

It presents the first detailed one-loop calculations of quartic and mixed Green's functions in QCD and QED at the symmetric point in a covariant gauge.

## Key findings

- Explicit analytical expressions for quartic ghost and quark Green's functions in QCD.
- Analytical results for gluon-ghost, gluon-quark, and ghost-quark 4-point functions.
- Comparable expressions for QED Green's functions are also provided.

## Abstract

We evaluate the quartic ghost and quark Green's functions as well as the gluon-ghost, gluon-quark and ghost-quark 4-point functions of Quantum Chromodynamics at one loop at the fully symmetric point in a linear covariant gauge. Similar expressions for the analogous Green's functions in Quantum Electrodynamics are also provided.

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Source: https://tomesphere.com/paper/1703.01094