Tales from the ArXiv: Centenary of Emmy Noether's Invariante Variationsprobleme

This article commemorates the centenary of Emmy Noether's article Invariante Variationsprobleme.

Title: On the Wonderfulness of Noether's Theorems, 100 Years Later, and Routh Reduction

Author: Raphaël Leone

Abstract: This paper is written in honour of the centenary of Emmy Amalie Noether's famous article entitled Invariante Variationsprobleme. It firstly aims to give an exposition of what we believe to be the most significant and elegant issues regarding her theorems, through the lens of classical mechanics. Despite the limitation to this field, we try to illustrate the key ideas of her work in a rather complete and pedagogical manner which, we hope, presents some original aspects. The notion of symmetry coming naturally with the idea of simplification, the last part is devoted to the interplay between Noether point symmetries and the reduction procedure introduced by Edward John Routh in 1877.

"Party-Time Symmetry"

Note: "PT Symmetry" stands for "Parity–Time Symmetry", not "Party-Time Symmetry", unless you're tired, in which case the latter may be the way that you read the abstracts of certain papers.

I'm pretty sure that Big Audio Dynamite was referring to PT Symmetry in one of their songs. :)

Choreographic Crystals!

Theorists have formulated a new kind of crystal that they have dubbed "choreographic crystals". Very cool!