Pontryagin

In my course this semester some of the theorems I have used were due to the Russian mathematician Pontryagin. His scientific work focused on topology first and later he moved into applied math. Since topology is a naturally visual subject, it's striking that Pontryagin was blind (although not from birth). A biography of him is available at this page, where they do not discuss some of his controversial activities, which can be found here, here, here, and in the article by Sossinsky here. He was a very angry and unpleasant old man.

The work of Pontryagin that I discussed in my course was on duality for locally compact abelian groups.  He came upon this theorem in his work on homology groups. The connection between those two topics is explained in the second half of this article.

The apartment building Pontryagin lived in is Dom 13 on Leninskii Prospekt:

Near one of the entrances to the building is a memorial bust:

The text says "In this building from 1939 until 1988 lived and worked the great mathematician Lev Semenovich Pontryagin."  There are a lot of memorial plaques on buildings in Moscow saying "[Important Person] lived here", and they may include an engraved picture, but if you put aside Lenin I have seen almost nothing like the sculpture for Pontryagin.  Pretty impressive.

Here's a wider view around the bust, to give a sense of scale:

Pontryagin is apparently looking across the street.  At what?  Here is a view that includes the other side:

It appears he is contemplating the advertisement for the new Harry Potter film (click on the photo to see the ad on the right side).  As an exercise, find the bust in the first picture of this post.