Eigenvalues and Eigenvectors

Joseph Mellor
16 min readSep 4, 2023

Eigenvalues and eigenvectors are the most powerful tools in Linear Algebra.

This article is part 7 in the How to Discover Finite Fields series.

We’ve talked about matrices and linear transformations in the previous article in the context of solving systems of equations, but there are often many cases where we have a linear transformation of a space to itself. In cases like that, we can repeatedly apply the linear transformation.

Repeatedly applying linear transformations can be quite time consuming. Furthermore, while the columns of a matrix indicate where we send the basis vectors, it’s difficult to interpret what’s going on with the matrices. The solution to both of these problems involves rewriting everything in the eigenbasis.

Prerequisites

While this is part of a series, you don’t need to know anything from the previous articles except what was covered in the previous article.

Motivation

While I’ve given some general motivation in the intro to the article, the motivation will become more clear if we give some examples.

Markov Chains

Say you live in a city where the weather on one day depends on the weather of the previous day with the…

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Joseph Mellor

BS in Physics, Math, and CS with a minor in High-Performance Computing. You can find all my articles at https://josephmellor.xyz/articles/.