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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2010

    this MO question on relative cohomology made me create an entry with an attempt to give the fully general abstract definition in the spirit of the discussion at cohomology

    a very stubby note is now at relative cohomology

    this clearly needs more development, but I think the basic idea is obvious

    • CommentRowNumber2.
    • CommentAuthorHarry Gindi
    • CommentTimeJan 23rd 2010
    • (edited Jan 23rd 2010)
    Sometimes I wonder whether all of the DAG formalism is strictly necessary for those kinds of pages. I mean, sure it may be incredibly useful, but you have to remember that the level of mathematical maturity necessary to get through HTT and DAG is definitely steep, even for the average graduate student. Is it the case that many of these concepts just don't have any sort "restriction" to the case of ordinary categories at all, or has the steering committee passed down a judgement that sophistication is more important than readability?

    I'm not saying this to disparage the writing style of any contributors here. I'm just saying that a large part of this site is entirely inaccessible to someone who is relatively comfortable with ordinary categories, and is it the material that is forcing this sophistication or is it just another incarnation of the nPOV?
    • CommentRowNumber3.
    • CommentAuthorTobyBartels
    • CommentTimeJan 23rd 2010
    • (edited Jan 23rd 2010)

    For my own part, is only laziness that makes me write something once and in a slick general fashion (although I don't write about these topics). I'm pretty sure that Urs agrees that it's good to give simple explanations accessible to 1-category theorists for the 1-categorial case (in fact, I think that he's already said so somewhere around here). It's helpful if people say what they're particularly interested in seeing a more accessible description of, as Todd recently did on another topic.

    • CommentRowNumber4.
    • CommentAuthorHarry Gindi
    • CommentTimeJan 23rd 2010
    I'll do that when I see specific cases come up. Thanks!
    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2010

    Yes, so a general point is that just because I write something in some way does not mean that I don't want to have something else be written. Quite the contrary.

    But recall what's going on here, from the HomePage: I am not being paid for running a site that answers other people's needs. If that happens, it's a pleasant side-effect.

    Instead, I use the nLab to jot down insights that I need for my own benefit. If now you come along and add your insight, or ask me something or the like, then we get going into a nice win-win situation.

    That said, let's be fair, maybe: I believe I and other regulars here are spending already more time on non-selfish tasks than some other people might think is good for us -- if you know what I mean.

    Anyway, the punchline is: if you feel an entry doesn't give you what you are looking for but don't feel youare the one to change this: drop query boxes, drop query boxes, drop query boxes.

    These boxes will sit their, patiently, and calmly keep asking everyone passing by to react. Eventually somebody will.

    • CommentRowNumber6.
    • CommentAuthorHarry Gindi
    • CommentTimeJan 23rd 2010
    I was just tring to kind of "bring the nLab's attention to" a problem you might not notice, since the a number of you (most of you?) do research in the subject of higher category theory. I fully understand that it's not really your responsibility to change things on the site, but I figured if I brought it up, you might think of it the next time you write an article. However, I am very away of the amount of time the regulars here put into this site and this community, and I really do appreciate it.
    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeJan 23rd 2010
    • (edited Jan 23rd 2010)

    right, I understand. But the only way out is if you and others join in and help out.

    For instance Eric Forgy, who has been a bit quiet lately, has done a great job pushing accessible expositions at a number of entries. Once somebody wrote something unintelligibly sophisticated, he would start asking concrete questions here, or put query boxes in the entry, or added himself stuff that was clarified in discussion.

    This here must be a "community undertaking", as it says on the home page, or it won't work. Myself, and other regulars here, have trouble finding enough hours in the day to do what I really need to do. There is just no way that each time I start writing an entry I try to do it in full textbook glory at once, starting with all the introduction, all the motivating examples, and slowly leading up to some more abstract point of view and so on. But I eventually want this to happen just as much as you do, really.

    It can happen, eventually, if everybody who cares joins in and adds his or her contribution. Don't feel shy about going to some unintelligibly abstract entry, and create a new section titled "low-brow-description" or the like. You don't even have to give that low-brow description if you don't feel you actually know what's meant. Just open a green query box and say things like "I suppose this relates to.. and the like". Then we'll all get going on developing this further.

    • CommentRowNumber8.
    • CommentAuthorHarry Gindi
    • CommentTimeJan 23rd 2010
    • (edited Jan 23rd 2010)
    I understand. Thanks for your efforts "at the front", as it were. Meanwhile, what happened to the nLab server?
    • CommentRowNumber9.
    • CommentAuthorTobyBartels
    • CommentTimeJan 23rd 2010

    Meanwhile, what happened to the nLab server?

    It was down, but now it's back.

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