2-Cocycle crossed products
نویسندگان
چکیده
منابع مشابه
A Crossed Module giving the Godbillon-Vey Cocycle
We exhibit crossed modules (i.e. certain 4 term exact sequences) corresponding to the Godbillon-Vey generator for W1, V ect(S ) and V ect1,0(Σ). Introduction There is a well known correspondence in homological algebra between (equivalence classes of) exact sequences Λ-modules, starting in M and ending in N with nmodules in between, and elements of ExtΛ(N,M). For Λ = U(g) the universal envelopin...
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ژورنال
عنوان ژورنال: SCIENTIA SINICA Mathematica
سال: 2011
ISSN: 1674-7216
DOI: 10.1360/012010-762