# Physics perspectives with heavy ions in the HL-LHC phase and beyond

## TL;DR

This paper reviews the current state and future directions of high-energy heavy ion physics, emphasizing the importance of small transverse momentum regimes and enhanced experiment-theory collaboration in the HL-LHC era.

## Contribution

It provides a comprehensive overview of heavy ion physics from a theorist's perspective and discusses potential future research directions and experimental-theoretical interplay.

## Key findings

- Highlighting the significance of small transverse momentum studies.
- Proposing improved collaboration between experiments and theory.
- Outlining future research directions in heavy ion physics.

## Abstract

The current state of research on high-energy heavy ion physics, including its motivations and purpose is reviewed from a theorist's perspective. Possible future directions are discussed, in particular the possibility of investigating the regime of small transverse momenta in more detail and an improved interplay between experiments and dedicated theory development.