Re: [FRIAM] Applications of category theory

2008-08-13 Thread John F. Kennison
Further thoughts on categories and their applications. References: Toposes. Theories and Triples can be found at Michael Barr's home page, www.math.mcgill.ca/barr/. The notes suggested by Jochen, below, are a good starting point. Applications: There are a lot of different types of categories

Re: [FRIAM] Applications of category theory

2008-08-13 Thread Carl Tollander
John, How do you feel about Goldblatt's book on Topoi? I've been working through it slooowly and like it so far, but I'm not sure whether it is leaving important things out. In particular, if you need something to understand the exposition, say, sheaves, then he goes back and tells you just

Re: [FRIAM] Applications of category theory

2008-08-13 Thread John F. Kennison
Carl, I have only skimmed parts of Goldblatt's book. It did look like it was trying to do the hard job of giving the important concepts of topos theory, along with the basic technical details. (it is easier to assume that the readers know category theory and also know how to digest a book that

Re: [FRIAM] Rosen, Life Itself - in context

2008-08-13 Thread Phil Henshaw
So, you get the representation of the unknown context of a thing by somehow knowing that the thing is not well described without it? How do you know what you're missing?I don't get where you propose the missing information to come from. Phil -Original Message- From: [EMAIL

Re: [FRIAM] Rosen, Life Itself - in context

2008-08-13 Thread glen e. p. ropella
Phil Henshaw wrote: So, you get the representation of the unknown context of a thing by somehow knowing that the thing is not well described without it? How do you know what you're missing?I don't get where you propose the missing information to come from. What? I don't understand.

Re: [FRIAM] Rosen, Life Itself - in context

2008-08-13 Thread glen e. p. ropella
Phil Henshaw wrote: You seem to suggest it is 'illformed' to have local knowledge and unanswered contextual questions. No, not at all. One can easily have an incomplete math representation of some aspect of a concrete thing. But one cannot have a complete math representation of some aspect

Re: [FRIAM] Rosen, Life Itself - in context

2008-08-13 Thread Phil Henshaw
OK. So perhaps you might be willing to change your question to: Given an INcomplete math representation of a button, how would you derive a math representation of a button hole? If you did that, then we might be able to formulate an answer. However, although that modified question is

[FRIAM] ComplexityNoodlersCorner, especially Rosen

2008-08-13 Thread Nicholas Thompson
All, The Wiki that supports this discussion suffered a calamity last week and has been moved, at least for the moment. The part of the address that used to read, .../wiki/... now reads .../mw/... . EVERYTHING else is the same. To find all the pieces, go to the NoodlersIndex at