What Lemma is

Students write a great deal of mathematics and almost none of it survives the term it was written in. An investigation gets handed in, marked and filed; a proof someone worked out properly for the first time ends up in a notebook. The work is often good. It simply has nowhere to go.

Lemma exists to give it somewhere. It publishes articles, investigations, essays, problem sets and reports across 9 fields of mathematics, and it keeps them. There are currently 0 pieces in the archive from 0 contributors, and nothing is ever taken down because it has stopped being recent.

Written by students

Every author here is at school. That is the point rather than a caveat: writing something up for a reader who is not marking it is a different exercise from answering a question, and it is the one that turns a result you can reproduce into a result you understand.

It also means the writing is pitched at the people doing the same courses. An article on the epsilon-delta definition is written by someone who found it confusing recently enough to remember why, which is not something a textbook can offer.

Refereed by students

Nothing appears without having been read by someone other than its author. Refereeing at Lemma is a genuine obligation rather than a formality — a referee reads the whole piece, checks the mathematics, and returns the places where an argument has a hole in it.

1. Proposal

   An author brings a subject and an angle. Most are turned around at this stage — usually because the piece would be a summary of a textbook chapter rather than an argument about it.

2. Drafting

   The author writes. Mathematics is typeset properly, figures are the author's own, and code is included when running it is part of the argument rather than decoration.

3. Request review

   The writer chooses an eligible reviewer and requests review. The reviewer reads the article, writes review comments, and approves or rejects it.

4. Revision

   If the reviewer rejects the article, the writer reads the review comments, revises the draft, and requests review again.

5. Publication

   An administrator or developer inspects the review comments and publishes the approved article. The public page shows Reviewed or Expert reviewed from the stored decision.

Not everything warrants the same scrutiny, so the archive says which kind of reading a piece has had. The label is on every card and at the foot of every article.

A publication, not a feed

Lemma is built as an archive first. Articles are filed under fields rather than dated into a stream, the search covers the full text of everything published, and every filtered view is a link that will still work in five years. A piece from two years ago is as findable as one from this week, which is the only arrangement under which writing something down is worth the effort.

Mathematics is typeset rather than screenshotted, figures carry captions and alternative text, and code blocks are highlighted from their source so that a reader can copy and run them. These are not features so much as the minimum for taking the writing seriously.