# Subrings of invariants for actions of finite dimensional Hopf algebras

## TL;DR

This survey reviews the structure and properties of invariant rings resulting from actions of finite dimensional Hopf algebras, summarizing key developments and open problems in the field.

## Contribution

It provides a comprehensive overview of invariant rings under Hopf algebra actions, highlighting recent advances and unresolved questions.

## Key findings

- Summarizes known results on invariants of Hopf actions
- Identifies gaps and open problems in the theory
- Connects Hopf invariants to classical invariant theory

## Abstract

This is a survey article on the invariant rings of Hopf actions