Is Renormalization in QCD Necessary at High Energy Colliders ?

TL;DR

This paper demonstrates that in high-energy QCD, renormalization of UV divergences is theoretically proven but not practically necessary for studying hadron production due to confinement, emphasizing the role of observable hadrons over partons.

Contribution

It provides a proof that renormalization is not required for high-energy collider studies of hadron production, contrasting with traditional views on QCD renormalization.

Findings

UV divergences are renormalized in QCD.

Infrared and collinear divergences factorize at all orders.

Renormalization is not necessary for hadron production analysis.

Abstract

In this paper by using the path integral formulation of the background field method of QCD in the presence of SU(3) pure gauge background field we simultaneously prove the renormalization of ultra violet (UV) divergences and the factorization of infrared (IR) and collinear divergences in QCD at all orders in coupling constant. We prove that although perturbative QCD is renormalizable but due to confinement in QCD it is not necessary to renormalize QCD to study hadrons production at high energy colliders. This is consistent with the fact that the partons are not directly experimentally observed but the hadrons are directly experimentally observed.