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    • CommentRowNumber1.
    • CommentAuthorAndrew Stacey
    • CommentTimeAug 9th 2010

    Slightly more honest than “nLab in the news!”. The article is really about MathOverflow but we do get a mention, and our “tag-line” gets quoted. Read the full article here.

    • CommentRowNumber2.
    • CommentAuthorzskoda
    • CommentTimeAug 9th 2010
    • (edited Aug 10th 2010)

    What is the preamble on our HomePage that we are keeping lying about nlab ? It looks nice as a joke on our wishful optimism...but is the first intro really a place for that joke ? I am not challenging it just want to know, probably I missed the discussion...(btw my first nForum post from my ubuntized laptop).

    Edit: corrected, thanks David.

    • CommentRowNumber3.
    • CommentAuthorDavidRoberts
    • CommentTimeAug 10th 2010
    • CommentRowNumber4.
    • CommentAuthorzskoda
    • CommentTimeAug 10th 2010

    Btw, could somebody be kind and remind me of the advice for xhtml vs html reading of local copy of nlab in firefox ? The wget prescription for downloading a local copy gives .html extensions, so the xml code is not properly rendered in firefox, unless one renames the files to xhtml when they render properly. Can I force firefox to behave differently, or what is the quick fix ?

    • CommentRowNumber5.
    • CommentAuthorMike Shulman
    • CommentTimeAug 10th 2010

    Zoran, I don’t understand your question in #2. Can you rephrase it?

    • CommentRowNumber6.
    • CommentAuthorTobyBartels
    • CommentTimeAug 10th 2010
    • (edited Aug 10th 2010)

    @ Mike:

    Zoran is asking about this quotation from the Mercury–News article:

    Several new math wikis share conversation and research, “like our lab book that we happen to keep lying around openly,” is how the popular site ncatlab.org describes itself.

    @Zoran:

    It is the first sentence under Purpose:

    We think of this wiki as our lab book that we happen to keep lying around openly.

    • CommentRowNumber7.
    • CommentAuthorJohn Baez
    • CommentTimeAug 10th 2010

    I’m very confused by Zoran’s question:

    What is the preamble on our HomePage that we are keeping lying about nlab ?

    even after Toby’s explanation. I can’t tell if Zoran thought this claim, “We think of this wiki as our lab book that we happen to keep lying around openly”, was a joke. I don’t think it was a joke.

    • CommentRowNumber8.
    • CommentAuthorzskoda
    • CommentTimeAug 10th 2010
    • (edited Aug 10th 2010)

    What are we lying ? We are probably subjectively optimistic about its future, but I do not understand which lying is in place ? I did not meet a nlaber lying about the nlab so far...

    Repaeting Q4: So how the firefox users on linux cope with xhtml vs html extension when trying to display properly the personal copy of (x)html lab dowloaded with wget prescription ?

    • CommentRowNumber9.
    • CommentAuthorTim_Porter
    • CommentTimeAug 10th 2010

    ”lying” has two meanings! Untruth or position!It makes interesting reading to look at each of the above entries for both meanings!:-)

    • CommentRowNumber10.
    • CommentAuthorzskoda
    • CommentTimeAug 10th 2010

    "lying openly" has two meanings ?

    • CommentRowNumber11.
    • CommentAuthorTim_Porter
    • CommentTimeAug 10th 2010

    There is ’lying openly’ and ‘lying around openly’. Perhaps ’around’ does change the meaning from the ’untruth’ sense to the ’position’ sense. That is an interesting example of the linguistic twists and turns of English (and my fellow countrymen always say it is such an easy language to learn and speak well. It is so complex to be positively opaque quite often.)

    • CommentRowNumber12.
    • CommentAuthorTim_Porter
    • CommentTimeAug 10th 2010

    Perhaps, on reflection the ’openly’ is not a good word, and ’open’ would be better. As you suggest, Zoran, the hint of the other meaning lingers there! How about: ’We think of this wiki as our lab book that we happen to keep lying open for all to see.’

    • CommentRowNumber13.
    • CommentAuthorzskoda
    • CommentTimeAug 10th 2010

    Yes open is much better in this meaning for non-native speakers like me!

    "We think of this wiki as our lab book that we happen to keep lying around open to everbody" or just "keep lying around open" would never confuse me. When I saw "lying around openly" it suggested to me an "open lie".

    • CommentRowNumber14.
    • CommentAuthorAndrew Stacey
    • CommentTimeAug 10th 2010

    I’ve changed it.

    The word “open” is actually grammatically correct here whereas “openly” is not. The correct meaning of the phrase is:

    We think of this wiki as our lab book that we happen to keep lying around and open.

    Thus, it is the lab book that is open, not the fact that it is “lying around”, and hence an adjective is correct (“open”) and an adverb is not (“openly”).

    In so far as I remember, the “lying around” is intended to make it clear that this is not particularly our primary motivation (contrasting with Wikipedia). Rather, our primary motivation is to make it easy to do mathematics and we think that keeping our lab book open will help us do so. However, that is also conveyed by the words “happen to” so I’ve removed the words “lying around”. Even though “lying around open” is unambiguous, given that “lying around openly” was misconstrued, I’m not convinced that the difference is enough for the word “lying” to remain.

  1. A related issue: why do we not adopt the policy of using MO rather than nForum for specific questions? This would allow us to:

    i) keep nForum more focused on nLab

    ii) have a larger audience for our specific questions (where larger should be in the set inclusion order: nForumers should get an MO account)

    This is part of my summer thoughts on the nLab, which one day I’ll try to focus and write. Basically, I’ve a feeling that nLab is becoming more and more encyclopedic and NPOV rather than nPOV oriented: lately we all have been adding more and more entries which are completely “classical” (for instance I can remember me creating Liouville cocycle and Hodge star operator a few weeks ago), when we could have better edited corresponding wikipedia entries in case we found them unsatisfactory.

    I see how selfsufficiency of the nLab is tempting, but I would rather invest on its specificity as the most powerful web reference for the n-category worker and on establishing strong connections (or reinforcing existing ones) with all the other math projects going on on the web (should we elect an nForeing minister? :) )

    • CommentRowNumber16.
    • CommentAuthorAndrew Stacey
    • CommentTimeAug 10th 2010

    Regarding MO versus nForum: I use MO when I don’t know who to ask about a particular question. If I know who to ask, why bother with MO? So when I write a question here, I have a fair idea of who I think will answer it. If I don’t, I’ll ask it on MO (or the categories mailing list) and maybe put a pointer to it there.

    • CommentRowNumber17.
    • CommentAuthorEric
    • CommentTimeAug 10th 2010

    I think we should all just continue being selfish and using any available resource we feel best helps us achieve our goals and not worry too much about what other people do.

    For example, if you want to stay focused on the nPOV and make the nLab the best reference in the world for n-category theory and its applications, by all means, do so. No one will force you to write an article on the Hodge star. If you want to ask questions on MO, do so.

    Take care of yourself and your needs and most everything else should fall into place as long as others do the same.

    • CommentRowNumber18.
    • CommentAuthorTobyBartels
    • CommentTimeAug 10th 2010

    If anybody wants me to look at a question, then they’ll get better results asking here than at MO, simply because MO is so much bigger that I read a much small portion of what appears.

    (Of course, they’ll get even better results emailing me. But I can understand that someone might want a public discussion, not to mention that they may be thinking of two or three of us when they ask.)

    As for the POV of the articles, while we do write some classical material (my personal extreme example is quadratic formula), we should expect to fit these into the nPOV. Even if what we write down is purely classical, by putting it on the nLab, those are the connections that we are encouraging.

    • CommentRowNumber19.
    • CommentAuthorHarry Gindi
    • CommentTimeAug 10th 2010
    • (edited Aug 10th 2010)

    Most of the time, if I write a question on MO that I think someone here could answer, I crosspost it here with a link to MO, so you guys can get the points.

    This has worked well, since it usually alerts Mike, Todd, or Urs to the question on MO.

    • CommentRowNumber20.
    • CommentAuthorzskoda
    • CommentTimeAug 11th 2010
    • (edited Aug 11th 2010)

    I disagree with Domenico #15 on two counts. First, the nPOV thing. All the mathematics is interrelated and having support of the topics which are a bit aside from contemporary understanding of nPOV and catPOV scopes still helps understand the mathematics, including back the topics which are more relevant to nPOV than the topic presently at the stage. I have expressed this opinion at the early days of nLaB including that I would not contribute to nLab if it becomes exclusive. One can not apply nPOV to concrete mathematics if one does not work on concrete math as well, hence we need concrete math in nlab. If somebody works on entries which are not in your interest at the moment you just ignore them. The same in nForum. On the other hand, people should try to use search button if some topic has been in nForum-latest changes before. I see that people open new topic like "Changes to the entry A" while there have been a month ago a discussion thread on entry A; this makes searching to old and related discussions a bit more complicated, so it is better to search if the thread for the thing already exists.

    As far as questions on MO versus nForum, I personally prefer them seeing here, if they fall in scope of people here. MO is less cleanly organized than nLab and hugely more wide in scope than nForum and looking through hundreds on entries on statistics, education, probablity etc. is much more problem there than here, exactly in line with Domenico's complaint on focus. So if Domenico does not like defocusing sites why he likes us to go to more defocusing site for questions :) ?

    Anyway, I think anybody with good intentions and reasonable level of sophistication should be welcome to contribute and choose any of the brave new math sites without pressure and political correctness.

  2. Zoran, I agree with you. So let me explain better what I meant: there are several entries in nLab which are created not because anyone is working on them but in what I would call a mixture of lazyness and anxiety of completeness (at least, these were my attitudes when I created a few of them). It goes as follows: I’m writing an entry I’m actually interested in, there is some technical term used in what I write, e.g. “hkjgkhj”. Since I’m lazy, I just duble-bracket it.. someone will come and will create the entry hkjgkhj, just to fix the nowhere pointing link and as a result hkjgkhj has its own page within the nLab. But actually hkjgkhj may happen to be a well known object, and I could have beel less lazy, and go and look if a wikipedia page existed, and see I I were satisfied with that. And then I could have directly linked hkjgkhj on wikipedia, evenually adding in a query box that I were not satisfied with the currest status of the wikipedia page on hkjgkhj. What I miss the point is why having a classical hkjgkhj entry here on the nLab before anyone has the minimal categorical insight on it. I would rather start new entries with an eventually really stubby (n-)categorical insight on some subject, and then to make itself readable I can imagine the entry being integrated with a classical treatment of the subject.

    So my invitation (mainly to myself) is not “Do not create and develop concrete math topics” but “Do not feel there is a necessity to have them here”. “Here” is such a funny word referred to the web :)

    As far as concerns MO, I will adopt Harry’s behaviour to post specific questions there and to post a link to them here on the nForum. Mainly to see if the larger audience I’ve in mind actually exists :)

    • CommentRowNumber22.
    • CommentAuthorHarry Gindi
    • CommentTimeAug 11th 2010

    There are really only three or four active category-theorists/ct-grad-students on MO who don’t participate on the nLab, and every so often an algebraic topologist might throw you a bone on a homotopy-theory-related issue, but I must say that MO is not all that great for ct questions.

    • CommentRowNumber23.
    • CommentAuthorzskoda
    • CommentTimeAug 11th 2010

    Now I disagree even more. First of all, the difference between nlab and wikipedia entry when the second exists should be in quality, rather than weather we have a categorical edge or not. Most math wikipedia entries have random references, often the most important are missed and the least important are having special sections. If the wikipedia entry is there, I still like to have a link to nlab page even if its main content is a link or choice of wikipedia material. This way it will be in source code available for personal copy of the nlab. And finally, I many times do not write about some entry, just because nobody started it before and the starting part like writing the most basic links (including to wikipedia!!), formatting redirects etc. is the most boring and misses the point of my interest in quetsion. Had somebody created a very stubby version I would put something in it. But if I have to write the stubby version first and then to write something what is on my mind and I have 20 minutes before the bus (mucg of what I do is in the evenings after all are gone from the institute and I am packing home), then I will probably not include a tiny new bit which was on my mind and which is maybe more critical.

    What I would agree with you is that writing a critical part of the entry (having subtle reasoning and formulas) should be done when one is in some sort of concentration, but i am leass favorable the imperative that one should not do "in lazy moments" trivial parts. If somebody misses the redirect it is easy to correct, but if somebody messes up the main text/definition and so on, then it is better not there and then I agree that sometimes one has to restrain.

    • CommentRowNumber24.
    • CommentAuthorzskoda
    • CommentTimeAug 11th 2010
    • (edited Aug 11th 2010)

    Domenico wrote:

    I would rather start new entries with an eventually really stubby (n-)categorical insight

    Go on...your preference on what you want to do today are yoru choice and I do not see their need to be discussed. If you have a more concrete idea and you want to share it and others following you it does not need to have justification in its relation to wikipedia and other web politics, make a blog entry or something and get us interested, just by magic of its content... :)

    Edit: Domenico wrote

    there is some technical term used in what I write, e.g. "hkjgkhj". Since I'm lazy, I just duble-bracket it

    I do not understand the motivation to do this particular phenomenon, I can admit. I mean, if you do not like to have its own entry in nlab why do you double-bracket it ?

    • CommentRowNumber25.
    • CommentAuthorMike Shulman
    • CommentTimeAug 11th 2010

    Re MO vs nForum, I think the nForum is better for open-ended questions that are likely to initiate discussions, whereas MO is better for questions that are likely to have an unambiguous correct and brief answer. Trying to have a discussion on MO is usually a no-starter.

    • CommentRowNumber26.
    • CommentAuthordomenico_fiorenza
    • CommentTimeAug 11th 2010
    • (edited Aug 11th 2010)

    But no, Zoran! you see, we completely agree, instead! what I’m saying is that having an entry on a classical subject on the nLab is truly worthy precisely when other available sources whcih could be linked are usatisfactory (and cannot with little effort be edited in a way making them satisfactory). So if a wikipedia or other entry on something is not good for us, precisely that is the moment we should have a better entry here. :)

    • CommentRowNumber27.
    • CommentAuthorzskoda
    • CommentTimeAug 11th 2010

    OK if we do agree :), I just see no need to make a manifesto/program out of it. At any stage everybody can decide if his/her effort in linking, expanding, documenting, creating, TOC-ing etc. is worthy effort or not. The experience and knowledge, and looking at each other, anouncing efforts and other evolutionary and working tactics will help to optimize and go away from childish blunders in that business, we may sometimes be frustrated at...

    Mike is right about discussion vs. answer. I often helped with answers in MO while never raised a question so far, though I plan one, where I exactly expect somebody to just know...(it is not easy to explain my question so I am postponing it).

    • CommentRowNumber28.
    • CommentAuthorTobyBartels
    • CommentTimeAug 12th 2010

    Domenico, you are considering the situation where you have occasion to write

    Let X be a foo. Then …

    where ‘foo’ refers to some classical concept that you have nothing to say about from an nPOV. Right?

    I would prefer it if there is a link to foo, because there may well be something nPOV to say about it; almost anything can be internalised or categorified, if we want to. But if you write a link to go straight to Wikipedia, as

    Let X be a foo.

    then if I later create a page with the nPOV content that you didn’t anticipate, then your link will never reach it.

    On the other hand, if you write an unsaturated link, then this is worse (for your page) than not linking to Wikipedia. One possibility is to create a page that says simple

    See Wikipedia.

    but I agree with you that it is not worth the effort to create this if you don’t anticipate any nPOV content. So I suggest a compromse position; write

    Let X be a foo (see Wikipedia).

    How’s that?

  3. then if I later create a page with the nPOV content that you didn’t anticipate, then your link will never reach it.

    very good point, Eric. and another possible problem with external linking is that on a page you could link to foo and in another page I could link to foo, and that would be bad.

    But maybe we can handle all this automatically (Andrew?). I mean, maybe is possible to have a file keeping a list of out-of-the Lab pointing links; then, when I create a link (an external one or one pointing to a still non existing nLab page) in an nLab entry, on submitting the page I get a message like “An external link for foo” already exist. Do you want to replace it with yours?” or “Do you want to create an nLab page?” Answering No would automatically replace my link with the existing one. Similarly, when creating a new nlab page I could get the advice: “An external link for foo” already exist. Do you want to create an nLab page?”

    • CommentRowNumber30.
    • CommentAuthorzskoda
    • CommentTimeAug 12th 2010

    I am not in favour in having microsoft-windows like warnings in every little action I do. If I am concerned with creating more links to nlab I will search for all kinds of notions which may have all kinds of names and may be relevant. Sometimes I do not want such a link. Having baloons around like your windows is not updated your windows is under risk of bla bla is something what kills my concentration if I get to windows with too many of such. There are good practices, Toby is one of the sophisticated in it, we can be better or not, but having computer suggesting me what to link to, when the search button exists, would be too muchin my opinion.

    • CommentRowNumber31.
    • CommentAuthorMike Shulman
    • CommentTimeAug 12th 2010

    I don’t agree that it is not worth the effort to create an nLab stub that does nothing but link to Wikipedia. It takes just two additional mouse clicks (once on the ? to create the page, then on “Save” to create the page) and no extra typing than it would take to just type “see wikipedia” in the original page. And it solves all the problems that have been raised with linking directly to Wikipedia.

    I also have trouble thinking of a mathematical concept about which one could expect to know in advance that there will never be anything to say about from a category-theoretic point of view.

    • CommentRowNumber32.
    • CommentAuthorMike Shulman
    • CommentTimeAug 12th 2010

    Also, it is worth having an nLab stub foo even if no one ever finds anything nPOV to say about it, because other people can then add new external references to that page in addition to Wikipedia, and anyone who gets to that stub from any page that linked to it will see all the new references. Moreover (modulo the redirect bug) once you are at the stub, you can see a list of all the other nLab pages which refer to it, which might also be useful if you are interested in foos.

    • CommentRowNumber33.
    • CommentAuthorAndrew Stacey
    • CommentTimeAug 12th 2010

    I certainly wouldn’t want any pop-up windows when I was typing a page. And also I wouldn’t want to have to be thinking “Is this a wikipedia link or an nlab link?”. Urs urges us to make links so if I’m to do that, I want it to be as easy as possible and just doing [[foo]] takes no thought at all.

    When I’m writing a page, I don’t want to be thinking about inessential stuff; I should be in “maths mode” and anything that gets me out of it is an irritation. I can clean up links afterwards when I’m at a lower level of concentration.

    • CommentRowNumber34.
    • CommentAuthorDavidRoberts
    • CommentTimeAug 13th 2010

    add new external references to that page in addition to Wikipedia, and anyone who gets to that stub from any page that linked to it will see all the new references.

    case in point: Zoran has made a few pages recently that are just collections of references to the literature, so that anyone interested in the topic can at least learn something in decent detail, and if they are motivated, put all their new-found knowledge into the stub.

    • CommentRowNumber35.
    • CommentAuthorTim_Porter
    • CommentTimeAug 13th 2010

    I noted that and thought : that is a good use of a lab-book! It could get out of hand if the list got too long but when looking for suitable places to start a topic it is an excellent method to proceed.

    • CommentRowNumber36.
    • CommentAuthorTodd_Trimble
    • CommentTimeAug 15th 2010

    I often write an article on something classical, not necessarily from an nPOV, just because I’m better able to learn or relearn it by writing about it than by reading a wikipedia article. That’s a completely selfish attitude I realize, but it’s in the spirit of the lab book lying around open, and I simply learn better that way. Besides, I find it fun to do.