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• CommentRowNumber1.
• CommentAuthorTyler Lawson
• CommentTimeAug 22nd 2013
I'm writing based on a suggestion by David Roberts.

We've been collecting together a list of open problems in homotopy theory on an instiki site here:
http://topology-octopus.herokuapp.com/
It was suggested that, for purposes of cross-pollination, hosting this as a sub-wiki of the nLab might be useful.

Selfishly, this would be beneficial to us for a few reasons. We're currently using a free hosting solution without many guaranteees of reliability, and I'm not particularly adept with the software for situations where something goes wrong. For this reason, the current site is not likely to be a permanent home.

However, we do understand that the role of these sub-wikis is to benefit the nLab and its contributors, and not merely a convenience for the general mathematics population. The main principals who have been putting this together are not workers in higher category theory and not regular nLab contributors.

As a result, I'd like to ask the steering committee if -- in the future -- migrating our material to a sub-wiki of the nLab might be considered.

• CommentRowNumber2.
• CommentAuthorUrs
• CommentTimeAug 22nd 2013

That’s an excellent idea!

• CommentRowNumber3.
• CommentAuthorTim_Porter
• CommentTimeAug 22nd 2013

I would support that, although I am not steering anything,;-)

• CommentRowNumber4.
• CommentAuthorDavid_Corfield
• CommentTimeAug 22nd 2013

Would it be possible to have a HomotopyForum too?

• CommentRowNumber5.
• CommentAuthorUrs
• CommentTimeAug 22nd 2013
• (edited Aug 22nd 2013)

Since the range of $n$ includes $n = \infty$, in principle there is no real need to have homotopy discussion separate from discussion here.

(But I gather that there may be some psychological barriers, even though maybe they needn’t be there.)

• CommentRowNumber6.
• CommentAuthorMike Shulman
• CommentTimeAug 22nd 2013

There is already an algtop email list, although it doesn’t get much traffic.

• CommentRowNumber7.
• CommentAuthorUrs
• CommentTimeAug 22nd 2013

There is already an algtop email list,

I suppose David was thinking of a forum for the wiki editing, analogous to this one here.

• CommentRowNumber8.
• CommentAuthorDavidRoberts
• CommentTimeAug 23rd 2013

we do understand that the role of these sub-wikis is to benefit the nLab and its contributors, and not merely a convenience for the general mathematics population.

I disagree to the extent that the nLab is used as a general resource, even if it started out as a place to archive our notes - I would be happy if the nlab server hosted the problems in homotopy theory wiki as a web - the benefits of being able to cross-pollinate outweigh any downsides I can think of. You might want your own url so as not to scare people off by using the nLab ’brand’ so conspicuously, but that is just an issue of implementation.

• CommentRowNumber9.
• CommentAuthorMike Shulman
• CommentTimeAug 23rd 2013

@Urs: Oh, I see.

@DavidRoberts: Yes, I agree that the scope of the other webs is potentially broader than just to benefit contributors, even if as a general rule we ask that someone establish themselves here first before requesting a personal web. A project of this sort seems like an eminently reasonable use.

• CommentRowNumber10.
• CommentAuthorDavid_Corfield
• CommentTimeAug 23rd 2013

@Urs #7: That’s right. Conversations about the wiki entries being edited might spark interesting discussion too.

• CommentRowNumber11.
• CommentAuthorTim_Porter
• CommentTimeAug 23rd 2013

One possible question is the extra traffic on the wiki site (and possibly on the forum). Would this slow things down?

• CommentRowNumber12.
• CommentAuthorUrs
• CommentTimeAug 23rd 2013
• (edited Aug 23rd 2013)

I can create the web this afternoon.

Did anyone hear of Andrew lately? Is he maybe on vacation?

• CommentRowNumber13.
• CommentAuthorAndrew Stacey
• CommentTimeAug 23rd 2013

No idea who Anrew is … is that my replacement?

Been around, but busy: moving back to Norway (from sabbatical) and then getting things ready for the start of term (which was this week). So I’ve been keeping an eye on things, but not saying anything if nothing needed it.

• CommentRowNumber14.
• CommentAuthorUrs
• CommentTimeAug 23rd 2013

Fixed, sorry.

if nothing needed it.

Technically there is a request to the steering committee here, and while I don’t expect you to object, maybe just say “Yes, I am in favor of creating a web for the ’Problems in homotopy theory’-project. “

• CommentRowNumber15.
• CommentAuthorjim_stasheff
• CommentTimeAug 23rd 2013
“Yes, I am in favor of creating a web for the ’Problems in homotopy theory’-project. “

Me too
• CommentRowNumber16.
• CommentAuthorTyler Lawson
• CommentTimeAug 23rd 2013

I'm going to repeat a little of what I just mentioned on algtop-L regarding forums. Because the scope of this project is so much smaller than that of the nLab, I think that a forum for the purposes of organizing the wiki would likely languish in disuse this point. (This is not to say that I object to the existence of a forum in general, but just that I don't think that we need one for this project yet.)
• CommentRowNumber17.
• CommentAuthorAndrew Stacey
• CommentTimeAug 23rd 2013

Sorry, Urs! I guess I was waiting for a discussion to be opened in the steering committee section to chime in with my “Yes, I am in favoUr.”. Plus the nature of the request was a bit vague: “in the future”, so I wasn’t thinking I needed to jump straight in.

Technically, migration should be quite easy since it is currently on an instiki installation. With regard to the forum idea, we could start with simply a dedicated category on the nForum and then migrate to a separate forum if traffic warrants.

• CommentRowNumber18.
• CommentAuthorTim_Porter
• CommentTimeAug 23rd 2013

we could start with simply a dedicated category on the nForum and then migrate to a separate forum if traffic warrants.

Great idea.

• CommentRowNumber19.
• CommentAuthorDavidRoberts
• CommentTimeAug 24th 2013

a dedicated category on the nForum

I thought that might be a good way to start as well.

• CommentRowNumber20.
• CommentAuthorUrs
• CommentTimeAug 24th 2013
• (edited Aug 24th 2013)

Have created the web now, here it is:

• CommentRowNumber21.
• CommentAuthorjim_stasheff
• CommentTimeAug 24th 2013
Don't want to try to edit but would like to add to the question about BG being an H-space that for topological G, there is aseries of obstructions, starting with homotopy commutativity.
Sugawara 1960: If (X,m) is a connected topological monoid, BX admits a multiplication iff m is strongly homotopy multiplicative.
• CommentRowNumber22.
• CommentAuthorTyler Lawson
• CommentTimeAug 24th 2013
David Roberts: You mention implementing a separate URL. What would be involved in setting that up with what Urs has implemented?
• CommentRowNumber23.
• CommentAuthorAndrew Stacey
• CommentTimeAug 24th 2013

To have a separate URL then you need to own that URL. Then you point it at the nLab and I set it up so that when a request comes for that particular URL then the request ends up at the homotopy problem web. So the first step is to choose and register a domain name.

• CommentRowNumber24.
• CommentAuthorUrs
• CommentTimeSep 2nd 2013

Just out of curiosity: I see that the new web hasn’t been touched at all. Do you need any help with migrating? Or did plans change? Should we remove the web again?