## July 8, 2010

### Grinding to a Halt?

#### Posted by David Corfield

The $n$-Category Café is grinding to a halt.

Lieven Le Bruyn attributes this decline to John’s shift in focus away from pure mathematics to more pressing environmental concerns. But, as I remarked there, I think it’s also largely due to energy that used to be expended at the Café now going into the $n$Lab and $n$Forum. [Discussions](http://www.math.ntnu.no/~stacey/Vanilla/nForum/?CategoryID=0) at $n$Forum are often just notifications of changes at $n$Lab, but sometimes they blow up into the kind of thing we used to do here.

I’d be interested to know from our clientele their thoughts on this shift. Are there any among you who would liked to have read and even contributed to plethysm, Schur functors, the long-running path category vs cobordisms for bundles or some other $n$Forum discussion, but who can’t see themselves seeking out what might interest them there?

I’d think it a great shame if we never hear again from some of the excellent people who have dropped by here over the years simply because of the change of venue.

Posted at July 8, 2010 12:03 PM UTC

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### Re: Grinding to a Halt?

For those, like me, who read a lot but barely participate, could you please explain the difference between the n-Cafe and the n-Forum?

Posted by: Tom Ellis on July 8, 2010 12:46 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

After nLab was set up to provide something more permanent than the discussions we had here – a working collective lab book – the nForum was set up to record changes made at nLab. Naturally as soon as people start discussing reasons for their changes, it developed into something larger, and you’ll now find there the sort of discussion we used to have so frequently here.

There may well be advantages as to platform and as to universal access to initiate discussion in the nForum. I was wondering if something had been lost in the process.

Posted by: David Corfield on July 8, 2010 1:42 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I was wondering if something had been lost in the process.

For me, the gains well exceed the losses. The nLab is a serious research tool in a way the Café could never be, and the participants in the nForum by and large share that seriousness of purpose. And I feel my own contributions gain far better traction there. There is no question that Urs feels the same way.

It feels funny to say that the energy that used to be here has gone into the nLab and nForum, since there are only about a dozen regular contributors there. It may well be the case, though.

(Which I actually like. I’m not that fond of big crowds. Even if there are hundreds of people who follow the nForum [are there???], I still get the feeling that I can have a semi-private conversation with someone over there, which I much prefer.)

Posted by: Todd Trimble on July 8, 2010 2:37 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I certainly don’t want to detract from the advantages of the shift, but to give a possible instance of a negative, I could imagine that James might have joined in the Plethysm discussion had it taken place here, in light of his contributions here and after.

Posted by: David Corfield on July 8, 2010 3:27 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Yeah, I’ve been watching things there at a distance, but I’ve been traveling and haven’t had the time to understand what’s going on.

Now that I’m writing this, I might as well mention the only thought I’ve had. The approach on the nLab involves symmetric groups in a basic way, but I would prefer to be on the other side of Schur-Weyl duality, working with representations of general linear groups instead of symmetric groups. I would expect this to work better in prime characteristic. I should emphasize that I’m not confident my opinion wouldn’t change after a bit of introspection, but I’m pretty sure that if your approach only works in characteristic zero, you haven’t really gotten to the bottom of things.

Posted by: James on July 8, 2010 8:00 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

In case it’s not obvious, one thing that we’re doing is proving the conjecture set out by John (over 3 years ago now! hard to believe) here.

Working in characteristic zero was a temporary decision we made just to test the conceptual waters, to see whether we could prove the basic conjectures in this easy case. We may be ready to branch out soon to other characteristics (or consider working over other modules).

We’ll certainly keep what you say in mind, about the other side of Schur-Weyl duality… you’ve clearly thought a great deal about this.

Posted by: Todd Trimble on July 9, 2010 7:17 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I see. Thanks for setting me straight.

Posted by: James on July 9, 2010 4:50 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

After nLab was set up to provide something more permanent than the discussions we had here – a working collective lab book – the nForum was set up to record changes made at nLab.

Since I suspect that there may be two or three researchers out there that remain unconvinced of the use of Wikis like the nLab, here is a praise, Wikis are very useful because:

• the Information is available online, that is I can use search engines like google to find the content I need, and I don’t need to carry around notes or books or the like,

• related topics can be linked,

• the content is free and editable, so I can expand and correct it anytime, and I can add topics from sources that are hard to come by (books that only few libraries have, for example),

• I get tips, feedback and input from others,

• writing for the nLab is like writing lecture notes, you get to rethink everything you thought you understand, find out what you don’t understand enough to explain it well and need to provide appropriate references for your claims.

And I strongly expect that the next generation of similar online knowledge bases, whatever it will look like, will provide some mechanism to import content from Wikis (or more generally from web pages) as we know them now, so that the work invested in the nLab will be preserved.

I use the nForum mainly to discuss topics that I would like to write about on the nLab, but that I need to discuss and get more information about before I can do that.

The topics range from pure category nomenclature related questions like what is a *-category to more general questions unrelated to category theory like superselection theory. That the focus of some discussions shifted from the nCafé to the nForum seems to be a purely sociological phenomenon…

Posted by: Tim van Beek on July 8, 2010 2:07 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Tim wrote:

I use the nForum mainly to discuss topics that I would like to write about on the nLab, but that I need to discuss and get more information about before I can do that.

It would be good to alert us café goers that such a discussion is open!

Posted by: jim stasheff on July 9, 2010 2:36 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

This is precisely what RSS is for :)

Posted by: Eric Forgy on July 9, 2010 3:51 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

David,
please don’t take my remark personal. I could have taken almost any (research) math blog to illustrate my observation that activity is slowing down (my own blog included).
in fact, what’s happening at the n-cat cafe is exactly the point i wanted to make, that math-bloggers are tired of the format and are looking for new ways to communicate math. The nLab and nForum are excellent attempts!

Posted by: lievenlb on July 8, 2010 1:09 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I certainly wasn’t taking it personally. I had long recognised that a vast portion of the energy has gone out of the blog. I quoted you as providing an outsider’s confirmation of this.

Yes, the nLab and nForum are excellent new initiatives. My query was whether something had been lost in the process. If so, it might be possible to rectify things. Often the good discussions at nForum grow unpredictably out of initial comments about small modifications to nLab. Perhaps we could get better at notifying the blogosphere when a discussion takes off. As it is, I’m not sure we’ll see some of the very best people who have contributed at the Café joining in these discussions.

Posted by: David Corfield on July 8, 2010 1:31 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

David,
your last point is an important one. Mathematicians are not the most flexible people around. It took them some time to get used to the blog-thing and they’re not willing to shift to another platform only because we bloggers are into exploring new things as early adopters.
I’ve met a similar difficulty last week at #noncommutative when I thought it might be fun to get a story across via an imaginary tweet-stream. It seemed to frighten people off… they thought i was becoming schizofrenic.

I’ll try to post something on all this tomorrow (I’m off to a BBQ). Thx for linking, tripling #noncommutative hits today…

Posted by: lievenlb on July 8, 2010 4:52 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I hope you generally get a decent audience. You’ve had some wonderful posts over the years.

I might say that I get a little confused as to your offerings. There’s the new #noncommutative, NeverEndingBooks, the n-Geometry Café, F_un mathematics. Some are presumably obsolete.

Posted by: David Corfield on July 8, 2010 5:01 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

David wrote:

Perhaps we could get better at notifying the blogosphere when a discussion takes off. As it is, I’m not sure we’ll see some of the very best people who have contributed at the Café joining in these discussions.

Amen! hard to participate if you don’t know a discussion is going on

and a discussion is very different from editing a n-lab entry

Posted by: jim stasheff on July 9, 2010 2:39 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I found Lieven’s Twitterification of the blogosphere a bit depressing, for various reasons. First, he sounded a bit glum, suggesting that “more science- and math-blogs are struggling to maintain an illusion of activity”, and linking this to the economic crisis. Second, I’d feel bad if my change of interests made the $n$-Café “grind to a halt”. Third, and more importantly, it came on the heels of his post noting that NeverEnding Books was not among the 50 best math blogs — at least, not according to some silly website. I didn’t like to ponder the possibility that some stupid list of math blogs might have caused someone with profound ideas and great expository skills to rethink the merits of blogging! And fourth, I don’t use Twitter and I don’t want to start… it affects me like the buzzing of gnats or the whine of mosquitos.

Posted by: John Baez on July 9, 2010 9:50 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

David wrote:

… long-running path category vs cobordisms for bundles or some other nForum discussion, but who can’t see themselves seeking out what might interest them there?’

don’t have time and energy to *seek*
I keep up with this venue because I get the RSS feed
and can quickly skim what’s ‘on offer’

Notice here of what’s on offer there does help
will try to find time to look at

path category vs cobordisms for bundles

Posted by: jim stasheff on July 8, 2010 1:12 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

You are a case in point. Whereas we hear from you frequently at the Café, unless I am mistaken we don’t at the nForum.

Posted by: David Corfield on July 8, 2010 1:49 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Hi Jim,

Here are the urls to the feeds I use:

I think you should be able to copy and paste the urls into whatever reader you use for the nCafe RSS.

Posted by: Eric Forgy on July 8, 2010 3:20 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

That “all comments” feed, for the $n$-Forum is a bit heavy for me; there’s nothing visible in common between last night and this morning! I wouldn’t know how much I’ve missed! (the easy answer is “all of it”, because I haven’t figured out how to read what I want to read… not knowing what I ought to want to read doesn’t help, either.)

One thing about ‘blogging (even group ‘blogging) that’s inescapable, really, is that it depends heavily on, and will tend to focus on the ‘blog authors. Apart from that, it’s rather flexible. One can ‘blog little blurbs, as here we hear about upcoming/in-process conferences; one can ‘blog pointers to other developed articles, as John does with his TWFs, or announcing his students’ and other friends’ papers from time to time; one can also ‘blog the articles themselves, as Urs and others have frequently done. David seems to like ‘blogging explicit promptings towards conversation, as in the present post. But in all cases it’s the ‘blog author’s focus that will keep a ‘blog focused, their participation that will encourage the participation of the audience. The authors may be (probably are) in it for the comment conversations, but most of us (the audience) start with the posts.

An open forum is, obviously, quite different. It’s more natural there to talk about whatever you like, just because it’s easier to create a new localized context for it. Both open fora and commented ‘blogs need some moderation, but in ‘blogging much of the moderation comes from the authors’ own careful choice of context, stemming from and maintained by their posting.

A wiki again is a stranger beast because of the competing pressures for polish and for expansion. There is also the apparent anonymity of a wiki article — you may see the original author or latest editor or both; for more info one must ask to inspect the history.

So, some suggestions:

It’s natural to view a ‘blog as a journal or newspaper: it’s arranged chronologically, there’s a well-defined set of contributing editors, and probably some process for granting headlines to outside correspondents. It’s really easy to write letters to “the editor”, and reply to these, etc. Nowadays they come with syndication tools.

It’s natural to view a wiki as a reference reccord. It might be worth announcing both important wiki contributions and interesting new results in a journal (the ‘blog, that is). Also if you’re writing a paper it might be worth keeping in mind a wiki article, something between an abstract and an argument, and noting both if you ‘blog one or the other.

On the other hand, I sense that it’s not natural to have separate interfaces for editing the wiki and for announcing/discussing wiki edits. Now, I don’t know what’s common practise now, but there are those +– {: .query} … =– boxes, where discussion could take place, and has — but it wasn’t really a friendly interface, and really is too wiki-ish to serve as a sensible discussion forum. The wikipedia “talk” pages are even more difficult to use in that sense, but it’s handy that they are both built-in and keep a separate context for discussion from that for exposition.

I’m vaguely imagining an alternative at the moment

• where a single database includes both wiki articles and discussion threads;
• where, analogous to the nLab’s current Print | TeX | Source views there are options to view threaded and chronological discussion, each available interleaved with, after, or without the wiki article, for context…

I expect that’s enough to make J. Distler scream (the migration troubles alone… ! But then, there are the elves… )

It needn’t be much different from a discussion forum — roughly, the top post in any thread would be anonymous and editable, wiki-wise, but the following discussion would be cumulative, immutable and personal. Apart from that, the biggest difference would be however you go about preparing/delivering/rendering the different views of the whole mess — what’s done server-side, what client-side, when do you deliver what, what do you feed through rss…

And it’s all beyond me, to be sure!

Posted by: some guy on the street on July 9, 2010 6:17 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Good comment, well delivered…

Posted by: Bruce Bartlett on July 11, 2010 11:02 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I’m not an RSS feed guy. When I feel in the mood to hear what’s up at the $n$Forum, I just go to Latest Changes. But I feel I may be misusing that page, because it’s really for announcing the latest changes on the $n$Lab, and I’ve been using it to have long discussions about $n$Lab entries with Todd and others. Maybe we should be talking somewhere else on the n-Forum. But nobody has tried to kick me off Latest Changes… at least not yet.

Posted by: John Baez on July 9, 2010 10:21 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Now going to Latest Changes when in the mood is an option that would never have occurred to me! The RSS is the mood changer I appreciate.

Posted by: jim stasheff on July 10, 2010 1:17 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

With John I came originally from USENET discussion, if anyone still remembers what that is. When that ran into problems Jacques offered to set up a blog to satisfy our online discussion needs. For me this was first the “string coffee table”, then this one here.

On the one hand this was good. On the other hand it was a failed approach from the get go: for instamce it took me (too) long to realize that using a blog like I used to use USENET discussion runs into all kinds of problems. The main one being that readers perceive it very differently. The very relaxed and casual but highly productive technical discussion of USENET newsgroups we managed to force here a few times, but it never took off the way it used to.

I was remineded of all that when we set up the $n$Forum, initially just as a means to conveniently log our $n$Lab edits, when suddently plenty of people came in who never (and still not) posted messages to the blog, but were eager to discuss stuff on a forum site.

I am still recovering from the pleasant shock when Domenico Fiorenza joined the $n$Forum and started discussing with me plenty of old $n$Café-entries that I had posted here and on which I never got any feedback here. Made me think that I had maybe wasted some precious time looking for discussion partners in the wrong place. Or at least in the wrong format .

Finally, one last comment: as you may remember, I tried real hard in the beginning not to have the $n$Lab divert energy from the $n$Café. I kept advertizing the idea that the kind of discussion of $n$Lab-edits that we have now on the $n$Forum we should have here. Originally I had intended the $n$Lab as the scratch pad that _supports_ the discussion here. As you may also remember, the reactions (and plenty of them) from various $n$Café regulars that I got on this idea were devastating and I gave up on this advertizing campaing.

Posted by: Urs Schreiber on July 8, 2010 1:54 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Blogs are very nice for presentation (like e.g. Johns ‘weekly finds’, or initial postings), but I do not think that they are well suited for discussions, which often split into subthreads. In my view Usenet is much better for this. For instance, when I am not visiting the blog for a few days (which these days happens quite often because I lack regular internet access), I have to scroll through several pages of text in order to find if something relevant has changed (the ‘recent comments’ section is not threaded), whereas an ordinary Newsreader would simply present the discussion threads to me.

Is there perhaps a possibility to have NNTP service for discussions?

Posted by: Marc Olschok on July 14, 2010 6:05 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

It would be interesting to see the number of hits/day at the cafe, the lab, and the forum over say the past 6 months. Or perhaps the number of posts. That might give some indication of any activity trends. From deep in the peanut gallery, my perspective is that the focus is becoming more technical and more specialized. That probably means that more serious research is being done, which is good, but will this narrowing focus endanger the long-term survival of this site? I certainly hope not, even if I some of us may be unable to benefit from it anymore.

Posted by: Charlie C on July 8, 2010 5:17 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I think initially the simple excitement of blogging about math, physics and philosophy as a team, together with a bunch of people learning the basics of $n$-categories, lent the $n$Café a lot of energy.

Later, conversations became more technical. People who work full-time on $n$-categories started talking about more advanced topics — which the ‘spectators’, who learn things mainly by watching conversations on the blog, probably find hard to follow. Heck, even I can’t follow a lot of the stuff that people are saying these days.

This may be a natural progression. But personally I really miss talking about the basics. That’s one reason I want start blogging about something a bit less technical, where there are a lot more ‘basics’ to master, and a lot more people interested in the basics: namely, how scientists and mathematicians can help save the planet. I’ll do that somewhere else, since it doesn’t make sense to do it on a blog called ‘The $n$-Category Café’.

On the other hand, I’ve been taking a kind of vacation for the past week or two, and I’ve found that one of my favorite hobbies is pure math. I haven’t figured out what to do about that, exactly. It probably makes sense for me to keep writing some pure math papers, straddling the border of exposition and research. But I’m not sure how important blogging could or should be as part of this process.

I no longer feel that it’s important to get people interested in pure math, or highly theoretical physics. I used to think that. But now I’ve flipped, and I even consider them to be rather decadent pursuits. In part this is a reaction to spending so much time on them myself — but in part it’s because the more I learn, the more I feel our civilization is in trouble and we need smart people to do something about it now.

So, I feel my blogging should be focused on that. But pure math and theoretical physics are still incredibly fun. So I’m a bit conflicted. But I’ll work it out. And I hope the $n$-Category Café continues to flourish.

Posted by: John Baez on July 9, 2010 8:45 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

But pure math and theoretical physics are still incredibly fun. So I’m a bit conflicted. But I’ll work it out.

One possible way is timeboxing.

Example: If you plan a workload of 45h per week, you reserve 40h per week for your main job, working on ecology etc. (“Working”, on this coarse level, means everything from reading, research, exposition and discussion). 5h are reserved for you hobby, pure math and theoretical physics. Of course you are allowed to work more on every topic, the point is that if you meet your own constraints, you don’t have to have a bad conscience.

Posted by: Tim van Beek on July 10, 2010 6:50 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Tim, there is one potential flaw with your idea. Do there really exist people with a 45 hour work week.

Double that and you’re in the right ballpark :)

Posted by: Eric Forgy on July 13, 2010 4:58 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I’ve got a 40h / week contract, and I am in a position where I can organize my workload accordingly, so I hardly have to work overtime. And, on the average, there are 5 hours left over per week that I can spend on mathematics and theoretical physics, so, yes, there are people with a 45h/week workload :-)

My point is that, especially in the software industry, time management is a very important “soft skill”, especially in times when there is a conflict of priorities, but I did not learn anything about this during my time in academia…is this different in the USA?

(BTW: My time management guru tells me that you should plan only half of your time and leave the other half free for tasks that you don’t know yet that you will have to do, so, if you work 90 hours/week, it’s sensible to plan only 45 hours :-).

Posted by: Tim van Beek on July 13, 2010 10:45 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I think your time management guru is spot on. I probably do have 45 hours of scheduled work. That is my day job. All the ad hoc stuff gets done on nights and weekends :)

Posted by: Eric on July 14, 2010 3:44 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

As for feeling conflicted, I’m sure you will work it out. Tim suggests a way. The nice thing is that you don’t have to make a choice; it’s not either/or, but rather both. That’s a great position to be in.

My view is that your background in theoretical physics, pure math, and category theory arms you with tools to attack some of today’s planet-threatening problems better than most. By now, finding isomorphisms must be as natural for you as breathing, and that ability will surely lead you to discovering connections and solutions that have been overlooked in the past. It will be exciting! You will have a wonderful time and we all will enjoy and benefit from your efforts.

I also truly hope the n-Category Café flourishes. It is one of the best known math blogs, and as such attracts a large audience. Among the many who attend, there is a steady stream of new contributors, many of whom otherwise might not have collaborated to contribute to the important research facilitated by the nLab environment.

A concern is that unless core nCafé members commit to a serious effort to use the nCafé explain the wonders of their field to those lacking their deep knowledge, the popularity of the nCafé will decline and the hope of spreading the excitement of this still-young field will once again falter. It may take more than just commenting on the latest nLab discoveries. As we all know, teaching the uninformed about such an abstract topic is extremely difficult; it demands enthusiasm and great creativity. Sooner or later we all figure out that mathematics, physics, artificial intelligence, molecular biology, computer science, whatever all may be extremely difficult, but explaining them clearly to intelligent but uninformed people can sometimes be even harder. I feel that the nCafé is the best venue for teaching and informing and spreading the excitement needed to grow the community, and for attracting serious contributors as well. The nCafé has created a unique opportunity to expand this field.

John, you have done more than your fair share to promote this field. Now, the baton has been passed. There is a tremendous opportunity here. Here’s to success!

Posted by: Charlie C on July 11, 2010 3:01 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Charlie C wrote:

unless core nCafé members commit to a serious effort to use the nCafé explain the wonders of their field to those lacking their deep knowledge, the popularity of the nCafé will decline and the hope of spreading the excitement of this still-young field will once again falter. It may take more than just commenting on the latest nLab discoveries. As we all know, teaching the uninformed about such an abstract topic is extremely difficult; it demands enthusiasm and great creativity.

I hadn’t thought of that as a purpose of the n-cafe
but now that you point it out, it explains why there are so many many more viewers that contributors

Posted by: jim stasheff on July 11, 2010 10:19 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Yes, I think you are right about viewers vs. contributors. But having many interested viewers is a good thing, right? Some of them may become contributors, and others will spread the word about the site. And unlike many blogs, the viewers are generally very well-behaved.

I’m going to be unplugged for the next couple of days, but I hope that the thoughtful discussions in this entire thread lead to a clearer picture of what people want this blog to look like in the next year or two, and some plans for getting there.

Posted by: Charlie C on July 12, 2010 12:20 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I hope that the thoughtful discussions in this entire thread lead to a clearer picture of what people want this blog to look like in the next year or two, and some plans for getting there.

I’m pretty scarce around here nowadays for no good reason, so I’m not really in a position to give accurate thoughts. So instead I’ll do what I always do in this situation: throw a few spanners in just to claim I was involved in the discussion.

(Bruce, 10 minutes later). I had written a paragraph going through the reasons why I suspected the hosts were struggling to keep going at the n-category cafe, but then I deleted my paragraph, since I discovered that things seem to have been going okay, maybe it’s just me not being regular enough. There seem to have been about 15 posts in the last month, which looks healthy?

Posted by: Bruce Bartlett on July 12, 2010 5:56 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I had written a paragraph going through the reasons why I suspected the hosts were struggling to keep going at the n-category cafe, but then I deleted my paragraph, since I discovered that things seem to have been going okay,

Which is why I am a bit troubled that we have this thread with this title sitting here. People will draw conclusions from just the title. Which is not even a statement by one of us.

Dynamics has changed here, in quality and quantity. But I don’t see us grinding to a halt at all. Maybe I should make a post, Not grinding to a halt at all.

Posted by: Urs Schreiber on July 12, 2010 6:33 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

YES!

Posted by: jim stasheff on July 13, 2010 12:41 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I second (or third) that. I think Lieven is pointing to something real about the math blogging world in general, but I don’t think there’s strong evidence that this particular blog is grinding to a halt. Quite the contrary: this blog continues to publish great posts on a regular basis, despite John’s changes in direction!

Posted by: Todd Trimble on July 13, 2010 1:37 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Urs wrote:

Dynamics has changed here, in quality and quantity. But I don’t see us grinding to a halt at all. Maybe I should make a post, Not grinding to a halt at all.

I would never have put up a post with the depressive title “Grinding to a Halt?” But maybe it’s good to confront fears and work through them. Anyway, it’s done now.

I keep trying to think of a really good pun involving “not grinding to a halt”, “coffee grounds”, and “$n$-café”, but I can’t think of one. If someone can, maybe it should be the title of Urs’ post.

On the other hand, psychologists know that “Not grinding to a halt at all” is a terrible title for a post if you’re trying to convince people that your blog is not grinding to a halt. It puts the phrase grinding to a halt into their minds; the mere word “not” is unable to counteract this.

Furthermore, there’s the The lady doth protest too much, methinks effect.

For propaganda to be successful, you have to think about psychology.

Of course, if I were really interested in promoting this blog through propaganda, I would not be publicly talking about how to do it.

Posted by: John Baez on July 14, 2010 4:56 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I would never have put up a post with the depressive title “Grinding to a Halt?”

What a sensitive soul you are! So if someone expresses an opinion of something connected to you which is not positive, and you raise this as a question, that counts as depressive? How ever do you live?

Is this a cultural difference? I always knew I’d have a hard time living in the US, especially after they changed the title of my book.

Posted by: David Corfield on July 14, 2010 9:08 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

If you go to that link, up at the left Amazon also offers the British title and cover

Posted by: jim stasheff on July 14, 2010 1:06 PM | Permalink | Reply to this

### n-People are selfish… and rightly so

From the beginning, the nCafe (and String Coffee Table before that) has always been primarily a selfish endeavor. There is nothing altruistic about it. The participants, often geographically removed from one another, need a forum like this to move their own research forward. The String Coffee Table worked until Urs needed to interact more with others who may not care so much about string theory. So he began collaborating with others here on the nCafe. Still, most of his posts on the nCafe have been selfish in nature as well. “Here is what I’m working on. Here’s what I think about it. Please tell me what you think and PLEASE tell me if I’m wrong.” This openness has been great. If there are a lot of readers of the nCafe out there, it is because of this “window into the research world” of these people whom many people out there admire.

If the nCafe didn’t serve this selfish purpose, it wouldn’t survive. Period. The moment the nCafe stops being useful as a research tool to the authors, that is the moment it will grind to a halt. Which hasn’t happened by any means yet.

However, a shift is clear. The authors are finding the nLab and the nForum to be those tools that increasingly satisfy those selfish needs. The good thing is, those forums are just as open to the rest of the world as the nCafe. The window is still open. Thank goodness.

Now, hearing people moan about RSS is simply ridiculous. You’re showing your age John! :) This only shows that even pioneers grow old and set in their ways ;)

Anyone not using RSS today reminds me of those guys 10 years ago we used to laugh at who had their secretaries print out all their emails for them. Many still do! Anyway, I don’t know how anyone survives today without RSS. I know I couldn’t keep up with everything I need to keep with (and the nCommunity is a minuscule portion) if I didn’t have RSS.

Anyway, my point is that it misses the point to think of the nCafe as some altruistic vehicle whose purpose is to educate the masses about higher category theory. It is simpler than that. It is a research tool used for selfish reasons by selfish researchers who often have deadlines to meet and publication quotas to fulfill. Nothing more than that. We should just be thankful that these tools are “open” so the rest of us can sit back and watch from the sidelines as these great stories unfold. I’m sure we have only begun to see what these guys have to offer.

Posted by: Eric Forgy on July 13, 2010 5:28 AM | Permalink | Reply to this

### Selfishness is hard to define

it misses the point to think of the nCafe as some altruistic vehicle whose purpose is to educate the masses about higher category theory.

Why is educating the masses about higher category theory necessarly altruistic? Insofar as I am a higher category theorist, I think my career will benefit from as many people as possible knowing about and appreciating higher category theory! (-:

Moreover, I wouldn’t be too quick to assign purely selfish motives to other people. I personally often enjoy explaining beautiful things to other people, even when doing so doesn’t directly have anything to do with my research. I suspect that John derives similar pleasure from writing TWF, or he probably wouldn’t have kept doing it all these years. It’s selfish in the same sense that all altruism is selfish – we do it because we enjoy it, not just for the sake of others – but it’s not necessarily directly about moving our research forward.

Posted by: Mike Shulman on July 13, 2010 7:31 AM | Permalink | Reply to this

### Re: Selfishness is hard to define

Right right. I don’t disagree with you.

Maybe a better way for me to say what I was trying to say is that the author’s need to get out more than they put in or else the effort is a net drain. There are no personal sacrifices going on here for the greater good.

Question for John, without asking for a long thoughtful response, more like a “yes or no”, would you say that you’ve gotten more out of TWF over the years than you put in? Has it been a drain?

I’d be shocked to hear anything other than the obvious answer.

So it is hard to quantify, but I think what I was trying to say is that the authors need to feel their efforts are worthwhile. Since different people are motivated by different needs, what is worthwhile is certainly hard to define.

If your needs are driven mostly by research, then the forum is less important than the functionality and it is fairly easy to migrate among spaces such as the nCafe, nLab, and nForum (and MO).

Posted by: Eric Forgy on July 13, 2010 8:11 AM | Permalink | Reply to this

### Re: Selfishness is hard to define

Eric wrote:

Question for John, without asking for a long thoughtful response, more like a “yes or no”, would you say that you’ve gotten more out of TWF over the years than you put in? Has it been a drain?

No need for thought here: writing TWF has been very much worthwhile for me, in many ways. Mathematicians and physicists around the world know who I am, and this ‘fame’ has opened many doors. (For example, I wouldn’t have gotten this job here in Singapore if it weren’t for TWF. They all seem to think I’m a ‘category theorist’ — but they hired me anyway.) I’ve made lots of new friends. Comments and corrections from people around the world have taught me many things. I’m always happy when I get an email saying that someone learned something from what I wrote. And last but not least: I can look up stuff when I forget it.

Posted by: John Baez on July 14, 2010 5:04 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

I no longer feel that it’s important to get people interested in pure math, or highly theoretical physics. I used to think that. But now I’ve flipped, and I even consider them to be rather decadent pursuits. In part this is a reaction to spending so much time on them myself - but in part it’s because the more I learn, the more I feel our civilization is in trouble and we need smart people to do something about it now.

Phew, this hits me quite hard (that I’m in a decadent pursuit). But these are the tough facts I have to come to terms with…

Posted by: Bruce Bartlett on July 11, 2010 2:39 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Don’t worry Bruce. Rather than the corruptor of youth he seems to be taking himself for, John is being smiled upon by Plato and also by Descartes, Pascal, and Leibniz.

Posted by: David Corfield on July 12, 2010 8:44 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Thanks. But nevertheless let me open that fearful book on my bedside table, Storms of my Grandchildren

Posted by: Bruce Bartlett on July 12, 2010 5:27 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I think the truth is somewhere in the middle. Too much pure mathematics lacking contact with the real world may be a sign of decadence, but I think a culture without any pure mathematics at all would be a sad thing to behold, like a culture that has no art.

Posted by: Mike Shulman on July 13, 2010 7:35 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

If this were actually:

“A group blog on math, physics and philosophy”

it might attract a broader community of those interested in mathematics, physics and natural philosophy.

In the last few months that I have visited here, there has been a dearth of physics and natural philosophy.

To put it a bit baldly, this site seems like a Platonist-only Club.

Don’t get me wrong, pure mathematics is a noble pursuit and Platonic models of nature are fine and dandy, but some of us like to discuss the real thing sometimes.

RLO
www.amherst.edu/~rloldershaw

Posted by: Robert L. Oldershaw on July 9, 2010 3:11 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

To put it a bit baldly, this site seems like a Platonist-only Club.

It is definitely mostly about math, which is what I think that you mean to say here. But your phrasing is very ironic, since I believe that few (if any) of the hosts subscribe to mathematical platonism.

Posted by: Toby Bartels on July 24, 2010 11:28 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

One thing the nForum has going for it over the nCafe is that anyone can start a discussion on anything. At the nCafe, only the hosts can begin a discussion. Some people have said that this makes the forum more like a “cafe” than the nCafe is. Just by the nature of the beast, I think a blog is less suited to open freeform community discussion, and more suited to semi-coherent expositions by the people who run it – although those may of course spawn interesting community discussions.

On the other hand, while the nLab and the nForum have advantages when we want to “do real work,” I suspect that there are many more people who read the nCafe than there are who comment on it, and that many of these people are not interested in reading all the discussions at the nForum. And we want all of these people to enjoy reading the nCafe and keep coming back, so as to keep up the profile of the nCommunity and advertise all of the nifty ideas we’re coming up with over at the nLab and the nForum.

So I think we should make an effort to keep the nCafe alive, but recognize that its role has to change. Whenever something particularly interesting is happening at the nForum or the nLab, I think we should make a special effort to bring it over here and describe it for a more general audience; not just make a post like “go read this forum discussion!” but give more background and put it in a wider context. (The nForum does have a section called Notices which is intended to be more “blog-like”, but my feeling is that it isn’t really serving that purpose, not yet anyway.) We should also make an effort to continue posting here on purely expository or “entry-level” topics. I’ve tried to do that a bit, but I have very little time this summer; hopefully in the fall I can start posting more again.

Posted by: Mike Shulman on July 9, 2010 4:16 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Shulman wrote:

Whenever something particularly interesting is happening at the nForum or the nLab, I think we should make a special effort to bring it over here and describe it for a more general audience; not just make a post like go read this forum discussion!; but give more background and put it in a wider context. (The nForum does have a section called Notices which is intended to be more blog-like, but my feeling is that it isn’t really serving that purpose, not yet anyway.) We should also make an effort to continue posting here on purely expository or entry-level topics.

PLEASE all you nForum-ites or nLab-orers DO that

Posted by: jim stasheff on July 9, 2010 2:21 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

PLEASE all you nForum-ites or nLab-orers DO that

One of the problems is that Joe nLabo[u]rer can’t do that! It’s up to mine hosts to do the posting. This is the point of those “3000 things to read on the nLab” posts which appear every so often. Maybe it’s time for another one.

Posted by: Andrew Stacey on July 19, 2010 4:04 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

One of the problems is that Joe nLabo[u]rer can’t do that

True, but if you or any of the other regulars want to write a guest post along the lines that Mike suggested, you’d be very welcome. Just check that it’s syntactically valid using the comment editor, then email it to me or one of the other hosts.

Posted by: Tom Leinster on July 19, 2010 4:41 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

On the off chance that anyone missed it, I think the thread on ternary factorization systems is an excellent example of how and why we need to bring Forum discussions back to the Cafe, and the Cafe can definitely still be lively. The Forum discussion seemed to be winding down a bit when I posted about it to the Cafe, where half a dozen people turned up with some extremely relevant literature references, a description of some unpublished work and ideas, and a proposal for a connection with n-fold distributive laws. Now someone just needs to sit down and condense all of that into a good nLab entry.

Posted by: Mike Shulman on August 4, 2010 2:13 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

As the one who asked the Schur functor question, let me say that it never occurred to me to wonder where everyone had gone, and to track them to the nLab (and the nForum, which had never before today penetrated my consciousness).

Having looked at the nForum RSS feed, it’s definitely not what I’d like to read, as compared to the Cafe.

Anyway this seems more like a whine, from an old-timer who never contributed that much, than anything else. I only post it to add a data point to the “are we leaving anyone behind?” question.

Posted by: Allen Knutson on July 9, 2010 8:03 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Possibly the Schur functor thread and related plethysm thread at the nForum are outliers as far as nForum discussions go, because they grew out of the slightly novel experiment of writing a paper publicly via the nLab. Hence we are deep into some technical conversations there about the writing of the paper. Not all discussions there are like that.

Posted by: Todd Trimble on July 9, 2010 1:21 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Allen wrote:

As the one who asked the Schur functor question, let me say that it never occurred to me to wonder where everyone had gone, and to track them to the nLab…

Darn! You found out!

I’d been planning to post a blog entry “Schur Functors II” where I linked back to your original question and summarized the progress we’d made on answering it, with a link to the $n$Lab for details.

In fact, I’ll still do that as soon as the $n$Lab entry is ready (as of yesterday, it was still full of mistakes). It’ll be fun. But now it won’t come as a surprise.

I don’t see the $n$Lab or $n$Forum as a substitute for the blogging — at least, not for me. Blogging is good when I want to tell everyone about something, and then have a big conversation about it. The $n$Lab is a good repository of information. And the $n$Forum is a good place to hammer out $n$Lab entries. It could even become a good place for more general discussions of math, physics and philosophy. But that’s not quite the same as ‘telling everyone about something’.

Posted by: John Baez on July 9, 2010 7:47 PM | Permalink | Reply to this

### The trinity

Blogging is good when I want to tell everyone about something, and then have a big conversation about it. The $n$Lab is a good repository of information. And the $n$Forum is a good place to hammer out $n$Lab entries.

That’s it.

Posted by: Urs Schreiber on July 9, 2010 8:02 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Interesting discussion.

Obviously, if anyone has any suggestions as to how to make the nForum more outsider-friendly then I’d love to hear them. That it isn’t is more a function of lack-of-ideas and lack-of-time to implement the few that I have (together with not being sure which of the few are worth spending any time on). For example, the RSS/ATOM feeds are quite customisable and someone just interested in the discussions could subscribe to the feed from The Atrium part of the nForum, since any lengthy discussions are meant to get moved there (maybe we need to be a bit better at moving them there as well).

I find myself spending less and less time on the nCafe, and other blogs. My reason is that time spent on other people’s math blogs is not working time, it’s “goofing off” time. Necessary to have some spots of that in a working day, but I’ve plenty of other things that count as brainless activity to fill them that are, strangely, necessary in my job. Time spent on the nLab/nForum, on the other hand, is working time. I’m trying to do some actual mathematics on the nLab, and the nForum is where I tell people about the mathematics that I’m working on. (In fact, I like the fact that there is a separation between where I work and where I tell people about it, because I’m in two different “modes” when I do the two and so find it useful to separate the two in time.)

In summary, the nLab is where I work. The nForum is where I talk about it. The nCafe is where I … err … not sure about that one!

Posted by: Andrew Stacey on July 19, 2010 4:01 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Here is a graph of spr/smr usenet activity:

So it looks like 2000-2004 was the “golden age” of usenet discussions. After 2004, there was quite a decline, at least in quantity.

Some of the cool discussions moved to blogs.

I guess a “cool discussion” is one that actually increases your understanding of nature.

Gerard

Posted by: Gerard Westendorp on July 25, 2010 11:43 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Interesting. Is there a way to report usage statistics for the n-Category Cafe, n-Lab, etc. for say the past 12 months. It seems to me that John posted some kind of usage statistics a while ago. It would be useful to see if actual data indicates any changes in usage.

Posted by: Charlie C on July 25, 2010 12:51 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Charlie wrote:

Is there a way to report usage statistics for the n-Category Cafe, n-Lab, etc. for say the past 12 months?

The only easy way I know is to click on the little map on the blog main page, which takes you here. The information isn’t as detailed as you can get with other free services, but it’s still fun. Here’s the count of ‘hits’ from 6 September 2009 to 20 June 2010.

United States (US)	43,191
United Kingdom (GB)	13,865
Germany (DE)	11,619
France (FR)	5,869
Australia (AU)	3,882
Italy (IT)	2,704
Netherlands (NL)	2,632
Japan (JP)	2,506
Spain (ES)	2,322
Sweden (SE)	2,222
Switzerland (CH)	2,126
Poland (PL)	1,547
Portugal (PT)	1,355
China (CN)	1,274
Finland (FI)	1,155
Norway (NO)	1,116
Greece (GR)	941
New Zealand (NZ)	929
Russian Federation (RU)	903
Brazil (BR)	892
Belgium (BE)	891
Israel (IL)	767
Denmark (DK)	740
Austria (AT)	690
Czech Republic (CZ)	686
India (IN)	673
Singapore (SG)	547
Ireland (IE)	385
Europe (EU)	379
Argentina (AR)	367
Croatia (HR)	349
Hungary (HU)	281
Mexico (MX)	279
Korea, Republic of (KR)	276
Taiwan (TW)	247
Hong Kong (HK)	247
Thailand (TH)	246
Morocco (MA)	235
Iceland (IS)	213
Luxembourg (LU)	173
Bulgaria (BG)	164
Colombia (CO)	149
Ukraine (UA)	138
Philippines (PH)	131
Malaysia (MY)	119
Romania (RO)	119
Iran, Islamic Republic of (IR)	94
Turkey (TR)	90
Indonesia (ID)	81
Chile (CL)	79
South Africa (ZA)	71
Algeria (DZ)	69
Slovakia (SK)	62
Serbia (RS)	62
Vietnam (VN)	60
Estonia (EE)	56
Lithuania (LT)	53
Slovenia (SI)	43
Egypt (EG)	35
Jamaica (JM)	34
Saudi Arabia (SA)	33
Venezuela (VE)	32
Pakistan (PK)	23
Costa Rica (CR)	22
United Arab Emirates (AE)	19
Belarus (BY)	19
Peru (PE)	16
Latvia (LV)	14
Bosnia and Herzegovina (BA)	14
Uruguay (UY)	12
Asia/Pacific Region (AP)	11
Kazakstan (KZ)	8
Puerto Rico (PR)	8
Lebanon (LB)	7
Kuwait (KW)	7
Bolivia (BO)	7
Guatemala (GT)	7
Nepal (NP)	6
Guernsey (GG)	6
Syrian Arab Republic (SY)	5
Aruba (AW)	5
Cyprus (CY)	5
Macau (MO)	5
Armenia (AM)	4
Azerbaijan (AZ)	4
Albania (AL)	4
Macedonia (MK)	4
Qatar (QA)	4
Angola (AO)	4
Moldova, Republic of (MD)	3
Malta (MT)	3
Bahrain (BH)	3
Tunisia (TN)	3
Senegal (SN)	3
Nigeria (NG)	2
Sudan (SD)	2
Aland Islands (AX)	2
Jersey (JE)	2
Kenya (KE)	2
Jordan (JO)	1
Mali (ML)	1
Saint Lucia (LC)	1
Cambodia (KH)	1
Djibouti (DJ)	1
Ghana (GH)	1
Ethiopia (ET)	1
Panama (PA)	1
Honduras (HN)	1
Yemen (YE)	1
Reunion (RE)	1
Uzbekistan (UZ)	1
Georgia (GE)	1
Iraq (IQ)	1
Mauritius (MU)	1
Dominican Republic (DO)	1
Cuba (CU)	1
Oman (OM)	1
Mongolia (MN)	1


Not exactly moribund, though the Cambodians, Iraqis and Mongolians seem to have really lost interest.

Posted by: John Baez on August 4, 2010 5:11 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Thanks, John! Now to wait for 6-8 months and repeat the measurement. It should be interesting to see if any usage trends are developing.

Posted by: Charlie C on August 4, 2010 12:38 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

I took the “Archive list (whole encelada)”, saved it as text, and searched for dates.
This gives the following graph:

It does not show the number of comments, only the *new* posts.

Gerard

Posted by: Gerard Westendorp on August 15, 2010 10:04 AM | Permalink | Reply to this

### Re: Grinding to a Halt?

Interesting graph, Gerard. Thanks! This seems to provide a view into the level of activity of the major contributors to this blog. My understanding is that it does not account for nLab activity, however, so including nLab contributions might give a more balanced view of level of contributor activity. On the other hand, I think it is also important to understand if the level of “viewer” activity is changing significantly. To that end, a periodic review of the numbers that John posted above could serve as a useful indicator.

Posted by: Charlie C on August 15, 2010 1:48 PM | Permalink | Reply to this

### Re: Grinding to a Halt?

Gerard wrote:

“Encelada” is the nonexistent sister of the mythical giant Enceladus. An enchilada, on the other hand, is a tortilla rolled around a filling and covered with chili pepper sauce. The word “enchilada” comes from the past tense of a specialized verb meaning “to add chili pepper to”.

We eat a lot of enchiladas in Southern California. The phrase the whole enchilada, meaning ‘the whole thing’, derives from this dish. Nobody knows exactly why, though of course it sounds cool. This phrase goes back at least to Herb Kalmbach of the Nixon Administration — see this transcript from the Watergate trial.

But the really funny part is this: look at the top of the Wikipedia article Enchilada, right after the title! I swear I didn’t put that there!

Posted by: John Baez on August 16, 2010 11:17 AM | Permalink | Reply to this

### Hard to swallow; Re: Grinding to a Halt?

To make a commutative diagram out of this, don’t we need to add: