Minimal Nielsen Root Classes and Roots of Liftings
نویسندگان
چکیده
Given a continuous map f : K → M from a 2-dimensional CW complex into a closed surface, the Nielsen root number N f and the minimal number of roots μ f of f satisfy N f ≤ μ f . But, there is a number μC f associated to each Nielsen root class of f, and an important problem is to know when μ f μC f N f . In addition to investigate this problem, we determine a relationship between μ f and μ ̃ f , when ̃ f is a lifting of f through a covering space, and we find a connection between this problems, with which we answer several questions related to them when the range of the maps is the projective plane.
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