New post at Not About Apples.
The Galois Theory arc returns from its hiatus. Today we look at what we should mean by symmetry in the context of number systems, connecting the concepts of group and field. This leaves us just one step away from the Fundamental Theorem of Galois Theory, and only a few steps of away from one of the most important impossibility theorems of all time: there does not exist a formula for the solutions of a polynomial degree 5 or higher analogous to the quadratic formula.
Permalink: Symmetries of Number Systems