Formulae for Order One Invariants of Immersions and Embeddings of Surfaces
نویسنده
چکیده
The universal order 1 invariant f of immersions of a closed orientable surface into R, whose existence has been established in [N3], takes values in the group GU = K⊕Z/2⊕Z/2 where K is a countably generated free Abelian group. The projections of f to K and to the first and second Z/2 factors are denoted f , M, Q respectively. An explicit formula for the value of Q on any embedding has been given in [N2]. In the present work we give an explicit formula for the value of f on any immersion, and for the value of M on any embedding.
منابع مشابه
Formulae for order one invariants of immersions of surfaces
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تاریخ انتشار 2003