Remnant properties in Nielsen coincidence theory
نویسنده
چکیده
We give an extension to coincidence theory of some key ideas from Nielsen fixed point theory involving remnant properties of free group homomorphisms. In particular we extend Wagner’s theorem for computing Reidemeister classes for Wagner characteristic homomorphisms, which allows us to compute doubly twisted conjugacy classes in many cases. We also extend Kim’s method for homomorphisms with bounded solution length, which leads to an algorithm for computation of the coincidence Nielsen number for mappings on surfaces with boundary whose induced homomorphisms on the fundamental group satisfy a natural remnant condition.
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