# Before MathOverflow

MathOverflow is almost ten years old now. Soon (if not already) the webpage will be old enough that some of the users may not have memories of the internet before MO. What were favorite (internet based, say) substitutes for MO before 2009 of current users?

• To misquote Brian Conrad: people lived in caves! – Lucia Dec 11 '18 at 5:22
• The nForum, but that was of course for a very specialised type of discussion :-) – David Roberts Dec 11 '18 at 8:16
• Mailing lists were a big thing. Still active and dating back to the 90s that I am aware of are the categories list and the fom (=foundations of mathematics) list. There were serious flame wars on fom about categories in the late 90s that I read on the archives with amazement (this was about a decade later). The diamond OA journal Theory and Applications of Categories was essentially launched on the categories mailing list. – David Roberts Dec 11 '18 at 8:30
• I will add a link to previous post on this meta related to @DavidRoberts' comment about mailing lists: Mailing lists / Usenet groups for research math. – Martin Sleziak Dec 11 '18 at 10:32
• Sitting with your friends in a bar and talking about math. – Asaf Karagila Dec 12 '18 at 9:16
• @Lucia You make me very curious. Mis- of which quote was that? – მამუკა ჯიბლაძე Dec 18 '18 at 5:17
• @მამუკაჯიბლაძე: Before functoriality, people lived in caves! – Lucia Dec 18 '18 at 6:04
• I wouldn't call them "substitute for MO". – YCor Dec 31 '18 at 10:35

For example, these newsgroups:
 sci.math sci.math.research sci.math.num-analysis sci.math.symbolic

See back in time to them HERE

• Gerhard "Hasn't Looked Back That Often" Paseman's answer incorporates USENET as well. It seems that USENET was very active once although the total volume of threads there is considerably less (~16000 in math.research) than at MO today (~100000). – Josiah Park Dec 17 '18 at 5:17
• sci.math.research was moderated and had a much smaller volume than sci.math (just as MO has a much smaler volume than m.se). – Gerry Myerson Dec 18 '18 at 2:28

Before MathOverflow, the culture of mathematics question-and-answers was quite primitive.

I remember the days when a student would impress their mathematics questions, expressed in cuneiform, by pressing with a stylus into clay tablets, and then bake them and carry them the next day to the summit of the mountain, to be viewed the next dawn by the gods. The priests would capture the birds at the summit who had seen the tablets, and divine the answers by inspecting their entrails.

In a major paradigm shift, it became common practice to write one's cuneiform in a transliteration of LaTeX, which led to far higher quality entrail output. Such students were the envy of their peers.

In later days, I had to march ten miles uphill in both directions through the snow, first depositing the computer tape containing my question at my supervisors pigeon-hole, and then later retrieving the dot-matrix printed output.

Finally, an oral tradition arose, whereby the students would ask their questions into the midst of a lecture, hoping for some kind of answer in signs. Oh, a wondrous day it was, when the answer to one's question appeared written on the chalkboard during the lecture!

• As someone who has to worry about lots of occurrences of $+1$ vs $-1$ in my work, it is definitely true that I am hoping for some kind of answer in signs. – LSpice Dec 19 '18 at 0:28
• P.S. I believe that the cuneiform markup language is properly called CLaYTeX. – LSpice Dec 19 '18 at 0:29
• What snow? Didn't you go to Berkeley? – Asaf Karagila Dec 24 '18 at 23:36
• @AsafKaragila en.wikipedia.org/wiki/Last_Glacial_Period#Northern_Hemisphere :-P – David Roberts Dec 25 '18 at 1:09
• Berkeley was for graduate school. There Joel just had to walk up hill to Evans Hall from home, and then walk up hill again to catch the homebound shuttle. Gerhard "Prefers Walking Up A Staircase" Paseman, 2018.12.24. – Gerhard Paseman Dec 25 '18 at 3:06
• I lived for a time in the Berkeley Hills, up on Grizzly Peak Road, so I had to walk up hill to get home, and getting to school, well, somehow I found this was also somehow uphill. In addition to the snow, there were often also earthquakes and vast fires. – Joel David Hamkins Dec 25 '18 at 5:06
• @David: Are you calling Joel a troglodyte? – Asaf Karagila Dec 25 '18 at 7:44
• @AsafKaragila just that he seems like he's been around here for ages :-) – David Roberts Dec 25 '18 at 23:23
• Old time MO user Noah Snyder also lived near Grizzly Peak, but he biked down to Evans Hall in the morning, then took his bus on the shuttle up to MSRI and rode downhill back home. – David E Speyer Dec 30 '18 at 19:19

IRC (Internet Relay Chat) had #math channels where people discussed concepts using an obscure dialect called ASCII.

There were moderated and unmoderated forums with thread based email discussions called USENET news. Some of them dealt with mathematics, and were remarkably free of spam and noise before some corporation bought them and made them publicly available (and opened the spam floodgates).

There were (and are) efforts by small groups to communicate by email and by web pages about various subject areas of mathematics. Although it was started earlier, by 1996 there was a repository of submitted scientific articles, some of which included mathematics, at Los Alamos National Labs. (Later Cornell took it over. It's called ArXiv.)

Some people shared their list of hyperlinks for internet resources. Occasionally a company would incorporate those lists into their curated databases. One of these companies was Yahoo.

The Wayback Machine has records of some of these pages. You might take a nostalgic tour one of these days.

Oh, and there really was no substitute for MathOverflow, primarily because the question answer format combined with a form of mathematical markup was still coming into its own. Also, there was no moderated group with such rapid turnaround as well as a scheme for community moderation. Living in caves and clubbing one another is not far from pre MathOverflow.

Gerhard "Hasn't Looked Back That Often" Paseman, 2018.12.10.

• The math irc channels were never at the level of MO. The only person I ever met there with a Ph.D. was Mariano Suarez-Alvarez. – Harry Gindi Dec 12 '18 at 6:25
• @Harry, I guess you were on the wrong network. mathoverflow.net/a/30695 was gleaned from a sci.math post which came from a discussion David and I had on #math. We also did some group theory, general algebra, and some combinatorial matrix theory back in the day. Gerhard "Guess You Had To Be There" Paseman, 2018.12.12. – Gerhard Paseman Dec 12 '18 at 15:21
• ArXiv started in August 1991: en.wikipedia.org/wiki/ArXiv – S. Carnahan Dec 21 '18 at 3:32
• @S.Carnahan, indeed. Do you know when they started accepting mathematics preprints? Gerhard "Not Up On The History" Paseman, 2018.12.20. – Gerhard Paseman Dec 21 '18 at 4:57
• That is a bit complicated. According to this page: arxiv.org/archive/math the first mathematics preprints were posted February 1992. On the other hand, we see from arxiv.org/list/math/9110 that there were 3 preprints from October 1991 that later got math cross-listings. Finally, it seems the "math ArXiv" as a separate entity with its own subject headings was initiated in December 1997: arxiv.org/new/math.html – S. Carnahan Dec 22 '18 at 4:52
• Thus my hedging. In any case, by 1996, they had several mathematics papers, if not a formal mathematics archive. Gerhard "Trying For Truth Over Accuracy" Paseman, 2018.12.21. – Gerhard Paseman Dec 22 '18 at 6:05
• There were other subject-specific preprint servers, much as the arXiv started out (for high-energy physics). One that stuck around for quite a while was the K-theory one faculty.math.illinois.edu/K-theory though it started in 1993, it seems. At the time there was a peculiar practice of removing the paper once it was published and keeping only the abstract; how quaint! Here's an old list of more, with a stack of broken links uni-math.gwdg.de/WorldMath/Preprints.html Perhaps the Wayback Machine can illuminate. – David Roberts Dec 24 '18 at 5:29
• Mathematical physics, mp_arc, dating back to 1991 web.ma.utexas.edu/mp_arc/mp_arc-home.html? – David Roberts Dec 24 '18 at 5:33

The Categories mailing list has been already mentioned in comments, I just want to add one detail, I think a significant one.

Mac Lane almost never posted there. I know several people that were sort of disappointed. Don't remember who told me this, but, when asked about it, he responded that such kind of communication was for birds.

He thus foresaw birth of Twitter many years ago.

• Could he use the word in sense 3: "a girl or woman, especially one considered sexually attractive"? – Emil Jeřábek Dec 24 '18 at 7:35

The Secret Blogging Seminar used to have a Requests thread, where people could suggest topics for us to write about.