Fundamental Lemma of CoV and the Euler-Lagrange Equations

This is the first entry in a series on the Euler-Lagrange Equations and the Calculus of Variations. The first main result I prove is the Fundamental Lemma of the Calculus of Variations. It’s a small but important result, used not only in CoV but also in the modern theory of Partial Differential Equations, where it underpins the definition of distributional derivatives. For that reason, I want to discuss it first. ...

May 30, 2026

Hello this blog

Hello, I am Victor and in this first post I will discuss my ideas and plans for this blog. First of all, I am going to write about topics I find interesting. These will mostly be in the context of Mathematics, Physics, and Computer Science. I will look for connections between these fields, but also going in-depth in particular topics. The main goal of these blog posts is two-fold: I can write about whatever I happen to be learning at that time, so that the new material will stick. Topics I am knowledgeable about I can discuss in-depth and expose what I find interesting. The target audience will differ per topic. Stuff that is new to me should target entry level readers. Mathematics I am knowledgeable about could target graduate level math readers. ...

May 22, 2026