# Comments on the chemical and kinetic equilibration in heavy ion collisions

## TL;DR

This paper critiques the adequacy of perturbative scattering models for describing quark-gluon plasma properties in heavy ion collisions, emphasizing the need for non-perturbative mechanisms and specific experimental measurements.

## Contribution

It highlights the incompatibility of perturbative approaches with experimental data and discusses the importance of non-perturbative mechanisms in QGP equilibration.

## Key findings

- Perturbative scattering models do not match lattice and heavy ion data.
- Non-perturbative mechanisms are crucial for quasiparticle rescattering.
- Experiments are needed to measure matter anisotropy and quark density.

## Abstract

I argue that perturbative scattering of quarks and gluons are incompatible with lattice and heavy ion data on QGP properties. The non-perturbative mechanisms for quasiparticle rescattering and quark production are briefly discussed, as well as experiments needed to measure matter anisotropy and quark density at early stages of the collisions.