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November 25, 2008

Beyond the Blog

Posted by David Corfield

With the publication of the first year of Terry Tao’s blog posts, appearing with the AMS, and the prospect of a second book on Poincaré’s legacies, I’m left wondering whether we are doing enough to make accessible the wisdom contained in this blog.

It’s quite common for me to be googling about for some concept and find that a forgotten conversation we had here many months ago is just what I’m looking for. The trouble is that our conversations are dispersed, and many individuals may be involved, so the effort to extract them for a Wiki, were we to have one, might be off-putting.

A low cost solution would be to form an index pointing to particularly good pieces of exposition. For example, there’s some great material on classifying toposes beginning here, with Tom, Todd, Robin and John contributing.

Posted at November 25, 2008 2:00 PM UTC

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17 Comments & 2 Trackbacks

Re: Beyond the Blog

I find that Google does the job very well! But I agree that an index would be useful.

Posted by: Jamie Vicary on November 25, 2008 4:41 PM | Permalink | Reply to this

Re: Beyond the Blog

A wiki can be built incrementally — it can start out as the index you just described, and before you know it people will jump in and make it much better. If it catches on, that is.

Jacques Distler has offered to host a wiki using Instiki on his computer. I’ve been too busy to even take him up on this offer. Maybe we (meaning, say, you) should start up the nLab using Instiki with his help. It can start off as a page containing links to posts with lots of good expository stuff. When I rejoin the world of people who can do new things, I can help add more stuff.

Posted by: John Baez on November 25, 2008 4:46 PM | Permalink | Reply to this

Re: Beyond the Blog

Yes! I think something like this would be a best seller! I often get hopelessly lost in a complex tangle of pointers to pointers to pointers when trying to get to the beginning of some topic and then trying to unwind back through the most relevant postings. This proposal might be the easiest way to start organizing the incredible wealth of information, experience and wisdom embodied here and also referenced from here. Making all this information more easily accessible would be a major contribution.

Posted by: Charlie C on November 25, 2008 5:52 PM | Permalink | Reply to this

Re: Beyond the Blog

yes, an index by all means
open source or moderated?

Posted by: jim stasheff on November 25, 2008 10:38 PM | Permalink | Reply to this

Re: Beyond the Blog

Allow me to say my two cents here.

  • A wiki would be nice, but we need to make sure it’s tailor-made for the situation we want, because small problems can cause its utility to suffer disproportionately.

    For instance, the search function on the n-category cafe home page is not terribly user friendly. It is very slow, and by default it only searches the blog entries (and not the comments). Getting it to search through the comments causes it to go extremely slowly, and by this stage I suspect most people get annoyed and don’t bother anymore.

    I first learnt of this deficiency from James Dolan many moons ago :-)

  • With regard to Jamie’s comment about using Google: the Google search is very powerful, but one has to be certain to use it correctly. A while ago John made a great comment about infinity groupoids, cobordisms and stable homotopy theory, in response to a comment by Jamie. I often find myself wanting to look this comment up and be reminded of it.

    But if you naively enter “baez vicary n-category cafe cobordism” into Google this comment does not appear!

    To get it to appear, one needs to add “site:” to the search, like this.

    I know all of you know this and are groaning, to think that I am even mentioning it!

    But it’s very important because otherwise naive Google searches don’t come up with the goodies.

    I have long asked for a link to such a “site::” Google search to be included on the main n-category cafe main page, and perhaps on every post page too. I think it would help a lot.

  • Regarding the index: Yes I think it’s a good idea. But how to do it? An index by itself already needs a kind of wiki.

    For instance, I am trying to learn the BV formalism from Urs’ posts. He has posted tons of stuff on this, including the 11 specialized posts linked to here. An index would be nice for this purpose. But I admit it takes some thought, it’s not as easy as it sounds.

Posted by: Bruce Bartlett on November 26, 2008 5:56 PM | Permalink | Reply to this

Re: Beyond the Blog

Heh, I must have muddled something up in my post. The “great comment” I refer to of John’s is at this link.

Posted by: Bruce Bartlett on November 26, 2008 5:59 PM | Permalink | Reply to this

Re: Beyond the Blog

Here is what we need:

a computer running MacOS or Linux, connected to the web and accessible via SSH, and the Administrator password of that.

Given that, Jacques Distler is offering to set up on this machine the kind of Instiki installation which he is running himself here.

I don’t currently seem to be able to provide these hardware prerequisites. If you do and want to help, please go ahead.

Posted by: Urs Schreiber on November 26, 2008 7:44 PM | Permalink | Reply to this

Re: Beyond the Blog

An alternative could be wikidot, a wiki hosting service. They include Latex support like WordPress does for blogs. See, for instance, qualympics.

Posted by: Mike Stay on November 26, 2008 10:21 PM | Permalink | Reply to this

Re: Beyond the Blog

Wow, I didn’t know about wikidot, it looks interesting (of course, Instiki is also cool!).

I noticed a bizarre side-effect of the way Wikidot renders LaTeX — it makes it possible to conceive of a webpage entirely typed, edited and displayed in LaTeX! See this comment I made at the site.

No doubt computer boffins will laugh at my suggestion, and say that I am completely out of touch with what the web is all about. But darnit, LaTeX output looks much better than anything I’ve ever seen on the web.

Think about it: the only time we ever use HTML here on the n-category cafe is when we make links or when we embed images. So these are the only things we need to add to make a 100% LaTeX wiki!

Anyhow, I know it’s just a crazy thought. I will go back to my hole now. For what it’s worth, I very much admire what Jacques has done with Instiki (I see there are theorem environments now, which is great).

Posted by: Bruce Bartlett on November 27, 2008 2:39 AM | Permalink | Reply to this

Re: Beyond the Blog

I use html for specifying italics and boldface, for specifying special characters such as em dashes and letters with diacritics, and for specifying blockquotes. Other people use it for those titles that pop up when you hover the mouse over the text. And what about embedded SVG? AFAIK, some of these, but not all, can be done with latex. And we already have something that works …

Posted by: Tim Silverman on November 27, 2008 3:50 PM | Permalink | Reply to this

Re: Beyond the Blog

I agree very strongly with Bruce’s suggestion here. I find it incredible that even today, with all the sophistication of Web 2.0, there isn’t an easy way to blog and leave comments in simple, pure LaTeX. It’s open source - what on earth is holding people back?!?

I know there are lots of things people have done to move towards this - the MathML we use on this blog, for example. But we’re still far from being able to easily write attractive, full-LaTeX mathematics on the web.

Wikipedia, in particular, should be very bothered about this. It’s no doubt become one of the best-loved resources for checking the details of mathematical definitions, but the mathematics often still renders appallingly.

Posted by: Jamie Vicary on November 27, 2008 4:26 PM | Permalink | Reply to this


Wikidot is the effort of some guy in Poland.

As with any hosted service, you have to wonder about whether they have a sustainable business model and what will happen to your data, if it turns out that they don’t.

One, now rather infamous, wiki-hosting service, Stikipad, didn’t, leading to a lot of very unhappy customers.

As an aside, is an Instiki installation running on a commercial webhosting service ($15/month). In the odd eventuality that none of you has access to a MacOSX/Linux machine of your own, that might be another route to go.

Posted by: Jacques Distler on November 27, 2008 7:57 AM | Permalink | PGP Sig | Reply to this

Re: Wikidot

Would it be hard to move the Wiki installation from one machine to another?

If not, we should just start with a rented server right now. When we have a better solution later we could still move.

Posted by: Urs Schreiber on November 27, 2008 4:49 PM | Permalink | Reply to this


While it can be configured to use other databases, by default, Instiki uses SQLite3, which means that your wikis (remember, you can run multiple wikis on one Instiki installation) are stored in a single file, db/production.db.sqlite3. Many people keep a copy of that file on a thumb drive, so that they can work on their wiki offline. It also serves as a complete backup1, which you could transfer to another machine.

There’s also the possibility to export an entire wiki as a zip archive of files in either XHTML or the original Markdown format. That, again, provides a mechanism for transfering your data.

1 If you use the file-upload feature, you also need to keep a copy of any files in public/NAME_OF_WIKI/files/

Posted by: Jacques Distler on November 27, 2008 7:09 PM | Permalink | PGP Sig | Reply to this

Re: Wikidot

that might be another route to go.

I now went that way. Have rented some server which should in a few hours be accessible under the domain

( is already taken).

Posted by: Urs Schreiber on November 27, 2008 10:15 PM | Permalink | Reply to this

Re: Wikidot

Cover him… Urs is going in!

Posted by: Bruce Bartlett on November 27, 2008 10:45 PM | Permalink | Reply to this

Posted by: Jacques Distler on November 28, 2008 6:08 AM | Permalink | PGP Sig | Reply to this
Read the post nLab
Weblog: The n-Category Café
Excerpt: We have set up a Wiki accompanying the n-Category Cafe.
Tracked: November 28, 2008 4:29 PM
Read the post The Microcosm Principle
Weblog: The n-Category Café
Excerpt: The microcosm principle finds aspects of the small reflected in the large.
Tracked: December 19, 2008 9:50 AM

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