Relative Cohomology and Projective Twistor Diagrams
نویسندگان
چکیده
منابع مشابه
Diagrams up to Cohomology
Let Sp denote the category of spaces, Ho the associated homotopy category, and D a small (index) category. A diagram in Ho with the shape of D is by definition a functor F : D −→ Ho. Given such a diagram one can ask whether or not it has a realization, i.e., a lift to a functor D −→ Sp, and if so, how many realizations there are up to an appropriate kind of equivalence. This question is studied...
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1991
ISSN: 0002-9947
DOI: 10.2307/2001494