I’ve recently become somewhat interested in smooth manifolds and surfaces as a result of preparation for various interviews, amongst other reasons. The concept of a surface is very intuitive, and is a concept that a student of mathematics is likely to encounter very early in their mathematical careers, though a reasonable definition of a surface takes more effort. The result of this formalisation is a remarkably elegant theory, which eventually leads to ideas of smooth manifolds - arguably one of the best sounding mathematical objects - and generalised calculus.

The ArXiv is a popular pre-print article server for physics, mathematics, and computer science (and other subjects) hosted by Cornell University. It is a fairly common practice for academics to upload a preliminary version of their articles (or other works) to the ArXiv to make them publicly available before they are formally published in a journal. (The process of publication is often lengthy, and many consider it best to make the article available in advance, even though it probably has not yet been peer-reviewed.

Zombies are a staple of modern popular culture, and appear in a variety of forms, including the traditional slow-moving, unintelligent zombie hordes and less common fast-moving - and perhaps intelligent - zombies. The common theme in media featuring zombies is the the zombie infection, which may affect either the living or the deceased, or both. It is generally agreed that this infection is passed from zombie to non-zombie by means of a scratch or bite, and infection always leads to a transformation into a zombie.