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• CommentRowNumber1.
• CommentAuthorzskoda
• CommentTimeJun 8th 2010

John Baez has erased our query complaining about disgusting picture at quasigroup, and left the picture. I like the theory of quasigroups but do not like to visit and contribute to sites dominated by strange will to decorate with self-proclaimed humour which is in fact tasteless.

• CommentRowNumber2.
• CommentAuthorMike Shulman
• CommentTimeJun 8th 2010

I don’t like the centipede pictures either.

• CommentRowNumber3.
• CommentAuthorTodd_Trimble
• CommentTimeJun 8th 2010

If it’s purely a matter of revulsion, would you be satisfied if the picture were replaced by something as innocuous as this?

• CommentRowNumber4.
• CommentAuthorzskoda
• CommentTimeJun 8th 2010

It is somewhat better, in the bottom feeling yes.

But I still have a minor complaint. Labelling quasigroup as something odd is a value statement undermining valuable mathematical research which some people do in that area. The entry centipede mathematics is a legitimate place which can be a place where one can do such evaluations, it is not dedicated to an awesome mathematical notion but to discussion of a sociological nature; but labelling mathematical notions in their own entries by value statements is a different issue. For example homogeneous spaces, something very central in nlab can be in certain formalism treated by loops in the quasigroup sense. Some people tend to find interesting very highly structured sets, while some like those with very little structures. It is hard to predict which ones will play role in a next revolution. Finally by Markushevich every statement in math can be described by a diophantine equation, and similar embeddings of one mathematics into another are yet to come in various areas. We can have separate entries on philosophy and sociology of mathematics, but definitions and similar entries dedicated to specific mathematical notions deserve respect toward mathematics. This is my opinion which is not necessarily correct or acceptable by others.

• CommentRowNumber5.
• CommentAuthorTobyBartels
• CommentTimeJun 8th 2010

I’ve removed the picture (which remains at centipede mathematics). (This is not intended to be a definitive act; it’s just what I did.)

If you missed it, John’s defence of the picture is here.

• CommentRowNumber6.
• CommentAuthorMike Shulman
• CommentTimeJun 8th 2010

It’s not about revulsion for me; I actually think the original picture is kind of cute. But it just doesn’t seem to fit to me. The nlab is about mathematics. We have this somewhat humorously named notion called “centipede mathematics,” and maybe we want to indicate which concepts are sometimes accused of falling under this heading, but what merit is there in having a picture of a centipede? Are we going to put a picture of a red herring on every page that refers to the red herring principle? Or a non-motivational poster on every page that refers to negative thinking? I think we should only use images that actually illustrate the concept being described and aid in the understanding of the mathematics. I don’t really even see the point of having the picture at centipede mathematics itself, but I can live with it there.

• CommentRowNumber7.
• CommentAuthorzskoda
• CommentTimeJun 8th 2010
• (edited Jun 8th 2010)

I think it is prefectly OK at centipede mathematics. This is a somewhat centipede entry so it can do the justice to itself. Red herring principle is a terminological convention or an intellectual reflection about the terminology in this or that case and, as the precise language is really important in mathematics, belongs in place in many concrete entries.

P.S. Yes, I have seen the defence, but as I said in n. 1 above, I did not share the feeling that there was any humour there.

• CommentRowNumber8.
• CommentAuthorHarry Gindi
• CommentTimeJun 9th 2010

Or a non-motivational poster on every page that refers to negative thinking?

This would actually be pretty hilarious. A picture of a poster that said something like “You’re a jerk!”

• CommentRowNumber9.
• CommentAuthorTobyBartels
• CommentTimeJun 9th 2010

Demotivational posters

(My dad is a big fan.)

• CommentRowNumber10.
• CommentAuthorIan_Durham
• CommentTimeJun 9th 2010

It’s not about revulsion for me; I actually think the original picture is kind of cute.

Ew.

• CommentRowNumber11.
• CommentAuthorDavidRoberts
• CommentTimeJun 9th 2010

I prefer the cartoon to the photo: the name is meant to be light-hearted, having a whopping big live centipede wriggling in a pair of tongs is not quite in the same vein for me. But I agree with Zoran, it belittles concepts to decorate them with pictures of crawlies.

• CommentRowNumber12.
• CommentAuthorIan_Durham
• CommentTimeJun 9th 2010

Personally, I think it would be much more effective with a screen-shot of the old Atari game, but maybe most of you guys are too young to remember that.

As for belittling concepts, there is a fine line between that and actual usefulness. The human mind is a wonderful thing and sometimes it uses associations like this to remember things. I don’t know the history of it, but clearly it is called “centipede mathematics” for a reason.

• CommentRowNumber13.
• CommentAuthorTodd_Trimble
• CommentTimeJun 9th 2010

Toby: I had meant to link to precisely that yesterday – you beat me to it!

Ian: the explanation of “centipede mathematics” is at centipede mathematics. You’re supposed to think of a ten-year-old kid plucking off pedes one by one and see if it can still crawl.

• CommentRowNumber14.
• CommentAuthorIan_Durham
• CommentTimeJun 9th 2010

OK, that’s a little morbid.

• CommentRowNumber15.
• CommentAuthorHarry Gindi
• CommentTimeJun 9th 2010

Bugs gross me out so I’m all for the cartoon.

• CommentRowNumber16.
• CommentAuthorIan_Durham
• CommentTimeJun 9th 2010

Bugs gross me out so I’m all for the cartoon.

Yeah, I’m not big on them either, though I’ve learned a lot about them from fly fishing…

• CommentRowNumber17.
• CommentAuthorTodd_Trimble
• CommentTimeJun 9th 2010
• (edited Jun 9th 2010)

Good there’s nothing about geoduck (pronounced “gooey duck”) mathematics, then.

Edit: and what the hell is that thing, you may ask? It’s a giant clam. Apparently it makes for excellent sashimi. :-)

• CommentRowNumber18.
• CommentAuthorIan_Durham
• CommentTimeJun 9th 2010
Indeed I have heard of geoducks. They are the mascot of Evergreen State College (I once wrote a blog post about strange college mascots).
• CommentRowNumber19.
• CommentAuthorJohn Baez
• CommentTimeJun 11th 2010
I don't care whether people get rid of the cartoon or not - go ahead and do what you want. It just seemed distracting to have a discussion about that cartoon on the page about quasigroups.

(I visited that page recently because I needed to remind myself of the definition of quasigroup. I'm planning to use it as an example of "centipede mathematics" in 'week299' of This Week's Finds, where I'll be talking about pre-Lie algebras. Pre-Lie algebras are gadgets that sound like examples of centipede mathematics when you first hear about them... but I've become convinced that they're somewhat important. I can also imagine learning to love quasigroups - it might help if I knew more about what people did with Latin squares.)
• CommentRowNumber20.
• CommentAuthorJohn Baez
• CommentTimeJun 11th 2010
By "cartoon" I meant "picture".
• CommentRowNumber21.
• CommentAuthorIan_Durham
• CommentTimeJun 12th 2010

it might help if I knew more about what people did with Latin squares.

Sudoku.

Or, if you're interested in serious applications, the problem of determining if a partially-filled square can be completed to form a Latin square is known to be an NP-complete problem.
• CommentRowNumber22.
• CommentAuthorTodd_Trimble
• CommentTimeJun 12th 2010

I would call that statement on NP-completeness more an observation than an application.

The Wikipedia article mentions an application to error-correcting codes, and this does look like an actual application.

• CommentRowNumber23.
• CommentAuthorIan_Durham
• CommentTimeJun 12th 2010

I would call that statement on NP-completeness more an observation than an application.

Yeah, I guess. But to a quantum computing person such a problem would be a way to test a quantum computer.
• CommentRowNumber24.
• CommentAuthorTobyBartels
• CommentTimeJun 12th 2010

Note that solving Sudoku is not really NP-complete, because we are given that the square can be completed, and what’s more can be completed uniquely. So solving Sudoku (if you trust the designer) belongs to UniqueP, which lies between P and NP.

• CommentRowNumber25.
• CommentAuthorIan_Durham
• CommentTimeJun 12th 2010

Note that solving Sudoku is not really NP-complete

I didn't mean to imply that it was. The Sudoku comment was separate from the NP-completeness comment.

With that said, let me clarify that quantum computers should offer a significant speed-up with these types of problems, but not to the extent of solving them in polynomial time. That is presently unproven (and suspected to be impossible by some).
• CommentRowNumber26.
• CommentAuthorHarry Gindi
• CommentTimeJun 12th 2010

The ideas behind quantum cryptography involve a lot less black magic than quantum computing/cryptanalysis. Also, quantum cryptography is unbreakable!

• CommentRowNumber27.
• CommentAuthorIan_Durham
• CommentTimeJun 12th 2010

Also, quantum cryptography is unbreakable!

Indeed. And it’s already commercially available.

• CommentRowNumber28.
• CommentAuthorMike Shulman
• CommentTimeJun 13th 2010

Also, quantum cryptography is unbreakable!

At least, in theory. (-:

• CommentRowNumber29.
• CommentAuthorIan_Durham
• CommentTimeJun 13th 2010

At least, in theory. (-:

Oops! Good thing I don’t own shares in ID Quantique…

• CommentRowNumber30.
• CommentAuthorJohn Baez
• CommentTimeJun 14th 2010
I thought that Latin squares were used in designing some experiments. But I never found out if this provided some interesting tricky questions about Latin squares.
• CommentRowNumber31.
• CommentAuthorIan_Durham
• CommentTimeJun 14th 2010

I thought that Latin squares were used in designing some experiments. But I never found out if this provided some interesting tricky questions about Latin squares.

Could be. I wonder if there's a connection to cellular automata. I seem to recall it's being used in some quantum computing experiments (maybe by the D-Wave guys? I'll have to ask Geordie.).
• CommentRowNumber32.
• CommentAuthorUrs
• CommentTimeJun 14th 2010

I agree with John that it is not good to leave a query box with a complaint for months, without any further action taken. It just makes an entry look bad to every bypasser, while those who might resolve the complaint are likely unaware of it. If there is a complaint, it should be taken to the nForum to find a resolution. If indeed no resolution can be found, we should leave a remark on the entry explaining the disagreement.

• CommentRowNumber33.
• CommentAuthorzskoda
• CommentTimeJun 14th 2010

There are many entries whicfh much larger imperfections than average query boxes which are signs of activity and which remind me often of past confusions and their resolutions. Sterilizing nlab in the name of nforum is not something I would like as a guiding principle. If it gets down to a dead discussion in nforum then it will be really dead. It is natural that everyone tends to have questions answered but where they are not, they should wait unless there is a natural moment for action (when one is thinking DEEPLY of something), rather than artifically closing it when one feels need to sterilize, though not on the day when one really clears up the issue in one's mind. The intellectual reasons should be a rule of change at nlab and not the sterile side of uniform aesthetics. I served in army and know what a uniformity means.

To John: are your pre-Lie algebras the same as what Dubois Voilette calls Lie prealgebras and which are defined in terms of Kosul duality in his case ?

• CommentRowNumber34.
• CommentAuthorHarry Gindi
• CommentTimeJun 14th 2010

I agree with John that it is not good to leave a query box with a complaint for months, without any further action taken. It just makes an entry look bad to every bypasser, while those who might resolve the complaint are likely unaware of it. If there is a complaint, it should be taken to the nForum to find a resolution. If indeed no resolution can be found, we should leave a remark on the entry explaining the disagreement.

Yes, if one of my query boxes is not resolved after a month, I will take matters into my own hands. =p

• CommentRowNumber35.
• CommentAuthorUrs
• CommentTimeJun 14th 2010

nLab entries are being referred to in other contexts. For that purpose it is annoying if an entry is sprinkled with complaints that could easily be dealt with. Army or not. There is plenty of forgotten discussion sitting in query boxes around the Lab. It serves no good purpose. A query box is good if it points to an unresolved issue. But easily resolvable issues should better be resolved.

1. That’s a good point. the fact is that often an unresolved query box is forgotten by it author, too. and since anyone else would probably avoid canceling it, it will remain there for ages. so it would be a good idea if we all look back at the query box we started to see their current status and eventually discuss them here on the forum. I’ll begin this now in another thread called “Domenico’s query boxes”

• CommentRowNumber37.
• CommentAuthorzskoda
• CommentTimeJun 14th 2010
• (edited Jun 14th 2010)

You guys are not listening: of course it is an idiot who would oppose to solve an issue if it can be solved well. But making the pressure to solve before one really attempts at true solution when the solution is not that obvious is not a good thing. There are factual inconsistencies and much more imperfection: i do not see why you claim that if we refer to an entry with quersy that is bad while thousands of immediate things in our interest or in entries which are unifinished wait. Did you say we should do things when they suit us ? When it is useful to think about ?

An example of similar nature. You have started few weeks ago an intense activity on tannakian categories; just at the moment when I entered an nforum discussion it was a coincidence that it was just about when you were stopping. So my last links and efforts got without response and you apologized as you had a turn into different things. So this was natural. Once you are back to Tannakian categories we will resume. Nobody should complain. That is natural sort of things. When you get back to the issue we will see what can we resolve. Now if somebody goes prematurely closing entries just as one feels it was few months and not because intellectual maturity on the issue has been reached. I feel this is nonsense. This is not an intellectual endeavour. So why would I contribute to such a community ? And what was the argument ? Just because you linked the page to some student ?? I do not undrstand. Is the intellectual effort first or this is service to people who can not scroll half a page ?

• CommentRowNumber38.
• CommentAuthorzskoda
• CommentTimeJun 14th 2010
• (edited Jun 14th 2010)

There is plenty of forgotten discussion sitting in query boxes around the Lab.

There are plenty of things nobody ever got to the point of intellectually resolving them. For example John Baez's question on coherence at D-module. If you want to give a half answer and remove the box, before a true discussion resolves that I am against it. If the box is easy to resolve as I said than I am for it and only idiot would be against it. But I am not going to do such a work as program, I will do whatever suits to improve those entries I am concentrated on, not more not less. In other words, you will not see an entry "Zoran's query boxes". If somebody raised a nontrivial query hard to decide what to do by others the entry is of sufficient closeness to the author that one will get back to the entry before or later. At least this is true for sustainers of nlab effort. So I do not see any need to do a list of personal queries. If somebody is so kind to do his, I have nothing against it, but this is number 100 on my own what to do list.

• CommentRowNumber39.
• CommentAuthorMike Shulman
• CommentTimeJun 14th 2010

Urs and Zoran, are you really disagreeing about anything? It seems to me that Urs is saying that query boxes that could be easily dealt with, such as those pointing to a simple stylistic or typographic disagreement or confusion, ought to be dealt with and removed, while Zoran is saying that query boxes with real content should not be removed without really resolving the issue, simply out of a desire not to have them there. I don’t see any conflict between these two statements and I agree with them both. Are there particular examples that you are disagreeing about?

• CommentRowNumber40.
• CommentAuthorHarry Gindi
• CommentTimeJun 14th 2010

I second Zoran’s position.

• CommentRowNumber41.
• CommentAuthorzskoda
• CommentTimeJun 14th 2010

I think we are not disagreeing about the real issues. That is why I said that Urs was not listening what I said. On the other hand, if there is a real issue and Urs feels strong about his program (like the self-cleaning Domenico started under that incentive) then I am going to be disobedient. That is why I emphasise the intellectual completeness/superfluousness at first place and not the absolute astronomic age of a query which was hastily quoted in the discussion before.

• CommentRowNumber42.
• CommentAuthorTodd_Trimble
• CommentTimeJun 14th 2010

Regarding Urs’s #32

If there is a complaint, it should be taken to the nForum to find a resolution.

I can’t see any reason to disagree with that. It’s up to the complainer to air the complaint publicly at the Forum for all to see, if he or she expects anything to be done about it. But whether it then gets resolved is something that has to occur naturally, as Zoran says. There is no time limit or pressure. (Harry #34: assuming you’re serious, an indication that you intend to take matters into your own hands on a specific point would be appreciated. Surreptitious modifications on possibly controversial points might not be too cool – I guess that goes without saying.)

If an unresolved query has been left sitting and it bothers someone who notices, it wouldn’t hurt to gently bring it up again, but I agree with Zoran that there is no shame or harm if a difficult-to-resolve question is left sitting there. Brief updates on the status, as Urs suggested, might be the best one can do in that situation.

• CommentRowNumber43.
• CommentAuthorTobyBartels
• CommentTimeJun 15th 2010

I agree with Zoran.

I’m not sure if there’s a disagreement with Urs or not. But I interpreted the last sentence of Urs #32 to mean that an unresolved query box should be removed and turned into a remark, which may not always be appropriate. (Sometimes it can be, when the discussion ends in ‘agree to disagree’, but really that’s a kind of resolution too.) And I definitely do not agree that query boxes make an entry ‘look bad’. On the contrary, they make a discussion look active, which is what it should be. Even for a query box that has been sitting untouched for months, it is too bad that the discussion has gone nowhere and it might be a very good idea to bring it up on the Forum, as Urs suggests. But since the casual reader cannot tell that the discussion has died, it still looks good!

Wikipedia went through a period where it people thought it important to look like a ‘real’ encyclopaedia, and this is part of what contributed to the sterile nature of much of Wikipedia today. (The main part is probably neutrality through blandness, but that’s a discussion for another day.) Wikipedia was meant to be (and still is) a perpetually unfinished encyclopaedia, so it really shouldn’t look as polished as a published edition of the Encyclopædia Britannica. All the same, at least Wikipedia is supposed to be an encyclopaedia. The nLab is supposed to be a lab book, which by its very nature is perpetually unfinished. So entries should be made more polished and complete as our understanding allows, but not for cosmetic purposes.

I think that the query box about the centipede picture at quasigroup is not really the same thing, since that query box was only about a cosmetic issue in the first place. So I actually do not feel strongly about John’s removing the query box there. But in general, query boxes should not be removed unless the issue is actually resolved. If they stick around for months, then it is worth trying to advance the discussion again, there or on the Forum. But if that doesn’t happen, then it’s better if they stick around than if they go away.

There are some query boxes that stick around for months after an issue has been resolved. I think that this is because nobody wants to be the one to remove it too early in case the other participants have more to say, and then they forget about them. But this is worth it if it means that people don’t remove them too early. When I come across these, then I make sure that the main text reflects what was discussed in them and then remove them.

• CommentRowNumber44.
• CommentAuthorIan_Durham
• CommentTimeJun 15th 2010
• (edited Jun 15th 2010)
I also agree with Zoran (not sure where Urs stands - perhaps there's no real disagreement here). Working on mathematics and science can be messy ventures at times and it is good for people casually stopping by to get a sense for how things get worked out rather than simply always presenting a polished finished product. This was recently discussed here.

As someone who's done a lot of work in the history of mathematics and physics, I can say that one of the lamentable things about the information/electronic age is that we're losing the written record - the "lab" notebooks - that used to be ubiquitous that gives us a sense for how scientists and mathematicians think. In studying, for instance, Gödel's work, there are manuscripts, handwritten notes, letters, and much else that one can retrieve from archives. If someone in the future wants to study Urs' or John Baez' work, I would guess much of the manuscripts and notes will be electronic (though perhaps these two save their handwritten notes - it was just an example) and letters have been replaced by e-mails which almost always eventually vanish into cyberspace.

In short, on behalf of future historians of science and mathematics, it would be better to not erase query boxes unless it is quite clear the problem has been directly addressed. Then someone going through the page history can make sense of the progression of thought for a given entry.
• CommentRowNumber45.
• CommentAuthorTobyBartels
• CommentTimeJun 15th 2010

On the Lab, at least, all past versions are saved (unless two versions in a row are made with the same signature within half an hour). So we only need to save query boxes containing unfinished discussions; the query boxes containing finished discussions are available to the future historians who comb through the nLab archives.

2. there are currently 444 pages containing boxes (not all of them are queries, in many cases a box is used to put something into evidence). by a random look at query boxes currently on the Lab, it seems a large number of them has been resolved, and are of that kind of very-quick-question-and-answer nowadays we would discuss on the forum (it should not be forgotten the Lab preexisted the forum, so there are old Lab-issues that now are better suited as forum-issues). so with little effort these many queries could be cleared and their content eventually merged in the Lab entries. on the other hand (and I’m sure we all agree on this, questions that are really open should be mantained).

I think that having a more cleaned up Lab is not only a service to Lab-readers (I mean, researchers or students non working on the Lab but consulting it), but also to the Lab itself (and so to Lab-workers). we have no hurry, the Lab is a long term project, if each of us clears just a box every two days, in no more than half a year we’ll have a nicer tool to do research with.

• CommentRowNumber47.
• CommentAuthorHarry Gindi
• CommentTimeJun 15th 2010

Could we make a forum thread that tracks all query boxes? That way they’ll be easier to keep track of.

• CommentRowNumber48.
• CommentAuthorAndrew Stacey
• CommentTimeJun 15th 2010

Do you mean manually or automatically? If manually, sure - just start one. If automatically, then a forum thread probably isn’t the right place. I could easily do a page in my webspace that each day listed (and linked) all the nLab pages with query boxes on them (indeed, anything that can be described in such a manner that a simple computer script could do it is possible so if there’s any other useful information/statistics that people would like, just ask).

• CommentRowNumber49.
• CommentAuthorHarry Gindi
• CommentTimeJun 15th 2010

If you could do it automatically, that would be great. That way, we can track them and resolve them instead of forgetting about them.

• CommentRowNumber50.
• CommentAuthorEric
• CommentTimeJun 15th 2010

It would be cool to have a category “nLab Queries” and when anyone enters a new query at the nLab it automatically creates a new thread on the nForum.

• CommentRowNumber51.
• CommentAuthorIan_Durham
• CommentTimeJun 15th 2010

the query boxes containing finished discussions are available to the future historians who comb through the nLab archives.

Right. My point, though, was that you want those page histories to have some sense of progression, if possible. So we shouldn't eliminate query boxes until they've been addressed. But I think we're all in agreement on that.
• CommentRowNumber52.
• CommentAuthorUrs
• CommentTimeJun 15th 2010

I don’t feel i have time for this discussion, so just a quick comment:

by all means, let’s have query boxes if there is need for them. But if its about trivialities such as formatting issues, try to take action and improve instead of just droppping a query box and waiting for somebody else to do the improvement.

Remember what triggered the discussion: John Baez removed a query box with the words:

It just seemed distracting to have a discussion about that cartoon on the page about quasigroups. […] I’m planning to use it as an example of “centipede mathematics” in ’week299’ of This Week’s Finds,

But also, I don’t quite care as much as this discussion is long.

• CommentRowNumber53.
• CommentAuthorzskoda
• CommentTimeJun 15th 2010
• (edited Jun 15th 2010)

If John Baez has a special purpose for a page, then the best advice is to copy the page to his personal part of the lab, and adapt it to special needs he has. I would do that if I had a special need to adapt a page to formatting or other standards not usual in the nlab community.

Urs: people brought many interesting things up, which are of further importance for planning our further activities.

• CommentRowNumber54.
• CommentAuthordomenico_fiorenza
• CommentTimeJun 15th 2010
• (edited Jun 15th 2010)

here is an example of query box which is unsolvable unless the Lab-workers involved do not explain their position: Connes fusion.

in the first version of the entry Urs mentions Wassermann’s paper in these terms: “The term Connes fusion for the operation originally defined by Alain is used at least since the article (Wassermann’s paper)”. Then, at a certain point Zoran remarked in a box that the term “Connes fusion” was surely in use before that.

now, how should I clean up that entry? everything depends on why the paper by Wassermann is cited there. if the only reason Urs cited it was to address the reader to the origin of the term “Connes fusion”, then according to Zoran’s remark I should just remove that citation. but if Wassermann’s paper is cited also because is is considered an unmissable reference for Connes fusion, then I should leave it there, and only change the line introducing the paper to something like “Connes fusion is used to define fusion of positive energy representations of the loop group $\mathcal{L}SU(N)$ in..” or something like that.

I understand that clearing query boxes is not on top of to-do-things for none of us, but I also think that we all should make a little effort to relovle those which can be easily resolved. for instance for Connes fusion, the only question to be answered is: is Wassermann’s paper cited as a source for the name or for being an important reference? ten seconds to answer this, and we’ll have a cleaned up entry (I can make the clean up, in case).

no need to say: nothing personal with Urs or Zoran, this was just the exaple I had under my eyes at this moment :-)

• CommentRowNumber55.
• CommentAuthorzskoda
• CommentTimeJun 15th 2010

It is certainly not cited for a name as the name was in wide usage at the time. It is an important reference in general field of operator algebras applied to conformal field theory and for having many fine technical points of importance. Maybe it has more value; Urs ? Without a question I am not against citing this paper, but not as the source of the name.

3. we have now 443 pages containing query boxes :)

• CommentRowNumber57.
• CommentAuthorzskoda
• CommentTimeJun 15th 2010

How do you know ?

• CommentRowNumber58.
• CommentAuthordomenico_fiorenza
• CommentTimeJun 15th 2010
• (edited Jun 15th 2010)

just search “query” in the search box. my post was referring to a previous post of mine where I was sayng that there were 444 such pages; now I’ve edited Connes fusion removing the box and citing Wasssermann paper in the brand new subsection “Applications”, as you suggested.

• CommentRowNumber59.
• CommentAuthorAndrew Stacey
• CommentTimeJun 15th 2010

I make it 431 as of last night.

• CommentRowNumber60.
• CommentAuthorTobyBartels
• CommentTimeJun 16th 2010

here is an example of query box which is unsolvable unless the Lab-workers involved do not explain their position: Connes fusion.

That is very appropriate, don’t you think? (^_^)

• CommentRowNumber61.
• CommentAuthorJohn Baez
• CommentTimeJun 16th 2010
• (edited Jun 16th 2010)
It would have been wiser for me to both delete the comment about centipede mathematics and post a comment here saying I'd done that and asking people to decide if they wanted to keep the picture. But I was in a rush, and I never expected it to arouse such passions.

Zoran: I don't know if "pre-Lie algebras" are the same as what Dubois-Violette calls "Lie prealgebras".

I've read a certain amount about pre-Lie algebras by now, but never heard them called "Lie prealgebras". Looking at Dubois-Violette's definition of Lie prealgebra, I am unable to quickly bring it down to a low-brow form where I can see if it is equivalent to the definition of pre-Lie algebra. However, I note that he doesn't refer to any of the literature on pre-Lie algebras, or any of the standard examples. So, if I were a betting man - and I am - I would bet that they're different.
• CommentRowNumber62.
• CommentAuthorHarry Gindi
• CommentTimeJun 16th 2010

@John: Would you like to make things interesting then?

• CommentRowNumber63.
• CommentAuthorzskoda
• CommentTimeJun 16th 2010

Thanks, John, my impression is also that it is a nonequivalent generalization. I wish I were more comfortable with Koszul duality; it is so important phenomenon which I understand so little. Of course there are few simple general nonsense formulations like HasegawaLefevre-Keller version using derived vs, coderived categories, but this is just a part of the story.

• CommentRowNumber64.
• CommentAuthorTobyBartels
• CommentTimeJun 16th 2010

It occurs to me that John may have thought the issue resolved at quasigroup, since there were no replies to his last comment. I just removed a query box at momentum for a similar reason.

It is hesitancy to remove these that leaves many boxes of the sort that I mentioned in the last paragraph of #43.

• CommentRowNumber65.
• CommentAuthorzskoda
• CommentTimeJun 17th 2010

I just removed a query box at momentum for a similar reason.

I disagree with this removal as well. This is an important reminder, and it is not easy to address it fully. It is not a weird list of exception but there are some general principles of mechanics. I can not dedicate to this issue within next 4 weeks at least.