
Π-Base – A community database of topological examples - colinprince
http://topology.jdabbs.com/
======
jdabbs
Author checking in. There hasn't been much user-facing progress on this
lately, but a colleague is currently working on a project to expand the scope
and content, and I've been tinkering on integrating with Coq (as time permits
(which is too infrequently)).

If you're interested in staying abreast, sign up for the newsletter
([http://jdabbs.us9.list-
manage2.com/subscribe?u=f81a0c2648f40...](http://jdabbs.us9.list-
manage2.com/subscribe?u=f81a0c2648f40a1dfa5003a74&id=9080bb12a3)). If you're
interested in getting involved, let me know
([https://twitter.com/jamesdabbs](https://twitter.com/jamesdabbs)).

------
aorth
HN news title currently using a captial Pi sign, aka П, which is the same as
the letter for "Pe" in many Cyrillic scripts. In fact, the Cyrillic letter
itself comes from the Greek symbol for Pi.

[https://en.wikipedia.org/wiki/Pe_(Cyrillic)](https://en.wikipedia.org/wiki/Pe_\(Cyrillic\))

------
stared
I was thinking about such think since reading Engelking's introduction to
topology. (When dealing with topology, it's so natural to think about both
implications, and examples of spaces (or, as importantly, counterexamples).)

------
hcarvalhoalves
Can someone explain the purpose of this database? The page doesn't give any
hints.

(I get it's math-related, but what is it useful for?)

~~~
jdabbs
The motivating use case is: I'm doing some topology research, and exploring a
new property P. I've determined how it relates to some well-studied properties
A,B and C (say A => P, P => B, and P => not C). I'd like a list of example
spaces that I can examine where P is interesting (spaces satisfying B, not C
and not A in this case). In general the hope is to streamline what is
currently a pretty tedious literature search, and to encourage researchers to
better pool their knowledge.

The other main use case now is educational - I definitely would have liked a
site like this when I was taking my intro to topology class and grappling with
examples to get my head 'round things, and I know of a seminar that ran using
the db as a hook to get students being self-directed, exploring, and
contributing more than undergrad mathematics usually allows.

Admittedly, that may not seem "useful" unless you're a topologist.

------
compactmani
Saving this link. Looks great at first glance.

