On homotopy types of 2-dimensional polyhedra
نویسندگان
چکیده
منابع مشابه
Homotopy 2-Types of Low Order
There is a well-known equivalence between the homotopy types of connected CW-spaces X with πnX=0 for n 6= 1, 2 and the quasi-isomorphism classes of crossed modules ∂ : M → P [16]. When the homotopy groups π1X and π2X are finite one can represent the homotopy type of X by a crossed module in which M and P are finite groups. We define the order of such a crossed module to be |∂| = |M | × |P |, an...
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1980
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-109-2-123-142