# The $n_f^2$ contributions to fermionic four-loop form factors

## TL;DR

This paper calculates the four-loop fermionic contributions to photon and Higgs quark form factors, providing analytical results for complex non-planar integrals involved in high-order quantum field theory computations.

## Contribution

It introduces the first analytical solutions for all non-planar master integrals relevant to four-loop fermionic form factors in quantum chromodynamics.

## Key findings

- Analytical expressions for non-planar master integrals obtained.
- Four-loop fermionic contributions explicitly computed.
- Enhances precision in theoretical predictions of form factors.

## Abstract

We compute the four-loop contributions to the photon quark and Higgs quark form factors involving two closed fermion loops. We present analytical results for all non-planar master integrals of the two non-planar integral families which enter our calculation.