Pseudo-Pontrjagin classes
نویسندگان
چکیده
منابع مشابه
Local formulae for combinatorial Pontrjagin classes
By p(|K|) denote the characteristic class of a combinatorial manifold K given by the polynomial p in Pontrjagin classes of K. We prove that for any polynomial p there exists a function taking each combinatorial manifold K to a rational simplicial cycle z(K) such that: (1) the Poincaré dual of z(K) represents the cohomology class p(|K|); (2) a coefficient of each simplex ∆ in the cycle z(K) is d...
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φx // Y If the diagram commutes, we must have that φx : B → Y be the map defined such that, φx(b) = φ(x, b) Thus the simple map φ on the product X ×B gives rise to a family of maps from B to Y that are parameterized by X. If exponentials exist, one can furthur assume the following two properties, (1) Every map B → Y occurs as φx for at least one x ∈ X. (2) φx = φy only if x1 = x2. Thus we write...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1985
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1985-0774016-1