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    • CommentRowNumber1.
    • CommentAuthorporton
    • CommentTimeJun 14th 2012
    I've added the following two new (related) pages to nLab wiki:
    category with star-morphisms
    abrupt category

    These concept aroused in my research of what I call cross-composition product (a stub in the wiki).

    See my research, especially this manuscript for details and examples.
    • CommentRowNumber2.
    • CommentAuthorTobyBartels
    • CommentTimeJun 14th 2012

    I don’t see why you bother with the pre-category [category without identities, what I’d call a semicategory] version. After defining categories with star-morphisms, it seems obvious enough to me what a semicategory with star-morphisms would be, but people don’t usually need semicategories anyway.

    Actually, I don’t see what the purpose of the concept is at all. Your research on funcoids etc is clearly not meaningless, but I don’t see the connections to the greater body of mathematics. (I’ve tried to read Funcoids and Reloids, but I find it wordy and unmotivated.) If you want to integrate your new research into the nLab, I can see the potential value of that, but it would probably work better on a personal web. From there, you could link seamlessly to established nLab articles, which (when relevant) could link back to your personal web’s pages.

    But even before that, you should establish yourself as a helpful contributor to what is already on the nLab. (Actually, that is a prerequisite for having a personal web; see also discussion on the policy.) Many of the regulars here are complaining (privately and publicly) that your work is inappropriate for the nLab, because it is obscure work that doesn’t connect to everything else that we do. Of course, much of the stuff on the nLab is obscure to the general mathematician, but at least we know how it connects, which we don’t know about your stuff.

    So if you first contribute to articles that are not about subjects directly related to your original research, then we can see that you’re a good scholar, then you can get a personal web, put your material on it, develop connections to the main nLab, then we can integrate it into the main nLab. Otherwise, we see you as a stranger writing in our lab book, so to speak, and your stuff will probably just be erased in the end.

    • CommentRowNumber3.
    • CommentAuthorporton
    • CommentTimeJun 14th 2012
    You say my research is not connected with the rest of mathematics.

    I disagree and give one such a connection:

    Cross-composition product may be useful to study multiple arguments functions (even multivalued functions) on proximity spaces. Multiple arguments functions on proximity spaces are obviously a well founded research field and this makes my research connected with the mainstream mathematics.

    That said I have not yet studied in details multiple arguments functions on proximity spaces. But I am almost 100% sure we will be able to research this in the terms of pointfree funcoids, a topic of my research.

    Just now I can't quickly make up other connections of my research with mainstream mathematics, but I think there are many.

    Should I put a note at cross-composition product that it is connected with multiple arguments functions on proximity spaces, to make clear for users of nLab that my research is not disconnected?
    • CommentRowNumber4.
    • CommentAuthorMike Shulman
    • CommentTimeJun 15th 2012

    Saying that something “may be useful” does not make a connection, nor does “thinking” that there are many connections. Even if one can rephrase subject X in terms of language Y, that does not make Y connected to mathematics through X. (E.g. one could rephrase all of computer science in terms of a Turing tarpit, but that does not make the tarpit interesting or connected to mathematics.) A further requirement is that Y provide some insight or tools or results that are of interest to mainstream mathematicians, particularly those studying subject X.

    If you could use your theory to prove something that was independently conjectured by mathematicians studying proximity spaces, then that might be a valid connection. Or if it gave some insight that they appreciated. But unless and until such a connection exists, the nLab is not a place for potentially blind-alley speculations. In order for a wiki-structured site to remain useful, it has to maintain a high signal-to-noise ratio. You understandably believe the subjects you have invented to be signal rather than noise, but without some evidence of that, they look like noise to the average mathematician (and thereby reflect negatively on the nLab).

    (As a piece of friendly advice, my experience suggests that valuable mathematics generally arises by building outwards from subjects that are understood and valued, rather than making up something totally new and then looking for connections to existing things. You are of course free to pursue whatever direction you please, but the nLab needs to preserve a certain baseline of value for its readers.)

    • CommentRowNumber5.
    • CommentAuthorMirco Richter
    • CommentTimeJun 15th 2012
    • (edited Jun 15th 2012)
    Also I'm not a regular contributor to the nLab let me make some comments, too. Since I'm into
    multisymplectic geometry (that is itself not a well accepted research field), I can
    partly understand your position:

    Even if there is yet not a well founded connection to the mainstream mathematics, there
    must be good reasons at least for you to put all that effort and time into your research. So to
    make people WANT to read what you are doing it is most likely a good idea to first explain
    why mathematics needs your work.

    What can we understand/do with your work that we can't with ordinary mathematics? What kind
    of problems does it solve? Why should I spend my rare time, to learn that stuff? Why do YOU
    spend your time on it? ect. ...

    I took a short look on your homepage and I can't find anything related to these kind of questions.
    There is only a vague hint to the 'epsilon-delta' criteria in metric spaces.

    Moreover you want people to designate you for the Abel prize! Serious man! If this is not some kind
    of self ironic humor, then it makes it almost impossible to take you serious.

    However these are just general thoughts and I don't want to talk you down since as I said I partly understand your position.
    • CommentRowNumber6.
    • CommentAuthorporton
    • CommentTimeJun 15th 2012
    Dear TobyBartels,

    You say I should do without pre-/semi- categories.

    Would you recommend to remove all mentions of precategories from my writings?

    Particularly one my manuscript which mentions precategories is now in peer review. Should I revise it removing mentions of precategories?
    • CommentRowNumber7.
    • CommentAuthorRodMcGuire
    • CommentTimeJun 15th 2012

    In the literature, “precategory” is mostly yet another name for quiver. I actually prefer this name because many notions from “category” (e.g. hom, functor, enrichment, slice, etc.) make sense in a precategory though their behavior is not as rich as in real categories.

    • CommentRowNumber8.
    • CommentAuthorTobyBartels
    • CommentTimeJun 15th 2012

    Whether you should include precategories/semicategories depends entirely on whether including them serves any purpose.

    I don’t actually say that you should do with out them. I say that I don’t see what their purpose is. And I don’t see what the purpose of categories with star-morphisms is. And I mostly don’t see what the purpose of funcoids is (although at least I know that they’re supposed to be an approach to general topology that includes both proximity spaces and pretopological spaces). And I mostly don’t see what the purpose of your entire research is either. That’s the problem.

    For general topology that includes proximity spaces and (not all but most in practice) pretopological spaces, I vaguely know Gerhard Preuß’s Convenient Topology. See this introduction with motivating properties of the system that make it sound attractive. Avoiding mention of ε\epsilons and δ\deltas is old hat, but cartesian closed categories of spaces are not.

    • CommentRowNumber9.
    • CommentAuthorporton
    • CommentTimeJun 15th 2012
    TobyBartels: You've said something like that cartesian closed categories of spaces is good.

    This is one of the research directions in my theory.

    I have defined several products of funcoids and reloids and reloids and other morphisms.

    The most interesting of them seems "cross-composition product" which maps any indexed family of pointfree funcoids into one pointfree funcoid.

    I have not yet proved that cross-composition product is a categorical product (not even formulated this statement exactly), but it seems very likely that cross-composition product can serve as a categorical product of such things as proximity spaces (where known products are somehow "bad").

    I write this reply only because you've praised "cartesian closed categories of spaces" and I need to respond to such your message.

    Also note that Gerhard Preuß's Convenient Topology is a special case of my structures.
    • CommentRowNumber10.
    • CommentAuthorTobyBartels
    • CommentTimeJun 15th 2012

    OK, that’s good: Preuß’s semiuniform convergence spaces are a special case of your funcoids, and funcoids also include all pseudotopological spaces (and not just the symmetric ones as Preuß’s spaces do). So if people like Preuß’s spaces (which certainly some mathematicians do) but don’t like that they leave out non-symmetric topological spaces, then this is a point in your favour.

    I wonder if you’d care to go through the 12 points that Preuß puts in favour of the category of semiuniform convergence spaces and say how many you know or suspect hold for funcoids (or reloids, or pointless funcoids, etc). Cartesian closedness is the first of these.

    • CommentRowNumber11.
    • CommentAuthorporton
    • CommentTimeJun 15th 2012
    TobyBartels: Not quite right. Preuß's semiuniform convergence spaces are a special case of my reloids, not funcoids. (Reloids is a very simple thing, a reloid is basically just a filter on a direct product of two sets.) But funcoids and reloids are closely related.

    I have not yet proved cartesian closedness of pointfree funcoids. So for now I am not able to affirm all 12 point (at least until I prove cartesian closedness).
    • CommentRowNumber12.
    • CommentAuthorTobyBartels
    • CommentTimeJun 16th 2012

    Can you say anything about the other 11? Whether for reloids, pointfree funcoids, or whatever?

    (By the way, is it correct that reloids and pointfree funcoids are both generalisations of funcoids? And are pointfree reloids a further generalisation?)

    • CommentRowNumber13.
    • CommentAuthorDavidRoberts
    • CommentTimeJun 16th 2012

    My advice to you, Victor, is to write first for yourself, and then for your blog, an essay which explains why you are pursuing this line. You should use no technical definitions, but be precise. If you have mathematical reasons why you are generalising spaces to funcoids then I haven’t seen them (not that I’ve looked at your work in depth, but every then I look just in case). By mathematical reasons I mean that you can prove theorems (see Mike’s second paragraph in #2) that otherwise are not easy, or awkward, or very difficult with the usual techniques/machinery.

    But from what little I have read you look like you have philosophical reasons why you want to work with your constructions (the ’algebraic’ in algebraic general topology). You should be aware that there is lots of research on generalising topological spaces along these lines for various philosophical reasons or foundational choices. Talking about how your work relates to these programmes will clarify your own thinking and may also help others see why you are pursuing this line.

    Until you can get to the point where you could motivate an average pure mathematician to want to think about funcoids, I don’t know think you will see any take-up of your work.

    • CommentRowNumber14.
    • CommentAuthorporton
    • CommentTimeJun 16th 2012
    TobyBartels: (By the way, is it correct that reloids and pointfree funcoids are both generalisations of funcoids? And are pointfree reloids a further generalisation?)

    Pointfree funcoids are a generalization of funcoids.

    Reloids CAN be considered a generalization of funcoids, because there is known an injection from the set (or proper class if you like) of funcoids into the set of reloids. But having a reloid it may be difficult to tell whether this reloids is a value of this injection. AS such I study funcoids by themselves not as a special case of reloids.
    • CommentRowNumber15.
    • CommentAuthorporton
    • CommentTimeJun 16th 2012
    TobyBartels: Can you say anything about the other 11?

    I quickly looked through the list. Many things in the list are very LIKELY to be true for my theory, but yet UNPROVED. Sorry, the work is underway.
    • CommentRowNumber16.
    • CommentAuthorporton
    • CommentTimeJul 26th 2012
    TobyBartels: "Avoiding mention of ϵs and δs is old hat, but cartesian closed categories of spaces are not."

    Now I am attempting to prove that my category cont(mepfFCD) is cartesian closed.

    But this stumbles over an open problem.

    Also: Maybe someone want to join my research, particularly to solve this problem?