---
tag: 0J1E5ZRZRM
kind: concept
name: Fixed field
msc: [12F10]
sources:
  - url: https://en.wikipedia.org/wiki/Fixed-point_subring
    locator: lead section
---

## Summary

The fixed field of a group of automorphisms of a field is the subfield of the elements that every automorphism in the group leaves unchanged.
The [[definition of the fixed field|0KMJ6919WS]] states it.